SystemUtils (Apache Commons Lang 3.18.0 API)

java.lang.Object
- org.apache.commons.lang3.SystemUtils

```
public class SystemUtils
extends Object
```
Helpers for System.
If a system property cannot be read due to security restrictions, the corresponding field in this class will be set to null and a message will be written to System.err.

#ThreadSafe#

Since:

1.0

See Also:

SystemProperties

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`AWT_TOOLKIT` A constant for the System Property `awt.toolkit`.
`static String`	`FILE_ENCODING` A constant for the System Property `file.encoding`.
`static String`	`FILE_SEPARATOR` Deprecated. Use `File.separator`, since it is guaranteed to be a string containing a single character and it does not require a privilege check.
`static boolean`	`IS_JAVA_1_1` The constant `true` if this is Java version 1.1 (also 1.1.x versions).
`static boolean`	`IS_JAVA_1_2` The constant `true` if this is Java version 1.2 (also 1.2.x versions).
`static boolean`	`IS_JAVA_1_3` The constant `true` if this is Java version 1.3 (also 1.3.x versions).
`static boolean`	`IS_JAVA_1_4` The constant `true` if this is Java version 1.4 (also 1.4.x versions).
`static boolean`	`IS_JAVA_1_5` The constant `true` if this is Java version 1.5 (also 1.5.x versions).
`static boolean`	`IS_JAVA_1_6` The constant `true` if this is Java version 1.6 (also 1.6.x versions).
`static boolean`	`IS_JAVA_1_7` The constant `true` if this is Java version 1.7 (also 1.7.x versions).
`static boolean`	`IS_JAVA_1_8` The constant `true` if this is Java version 1.8 (also 1.8.x versions).
`static boolean`	`IS_JAVA_1_9` Deprecated. As of release 3.5, replaced by `IS_JAVA_9`
`static boolean`	`IS_JAVA_10` The constant `true` if this is Java version 10 (also 10.x versions).
`static boolean`	`IS_JAVA_11` The constant `true` if this is Java version 11 (also 11.x versions).
`static boolean`	`IS_JAVA_12` The constant `true` if this is Java version 12 (also 12.x versions).
`static boolean`	`IS_JAVA_13` The constant `true` if this is Java version 13 (also 13.x versions).
`static boolean`	`IS_JAVA_14` The constant `true` if this is Java version 14 (also 14.x versions).
`static boolean`	`IS_JAVA_15` The constant `true` if this is Java version 15 (also 15.x versions).
`static boolean`	`IS_JAVA_16` The constant `true` if this is Java version 16 (also 16.x versions).
`static boolean`	`IS_JAVA_17` The constant `true` if this is Java version 17 (also 17.x versions).
`static boolean`	`IS_JAVA_18` The constant `true` if this is Java version 18 (also 18.x versions).
`static boolean`	`IS_JAVA_19` The constant `true` if this is Java version 19 (also 19.x versions).
`static boolean`	`IS_JAVA_20` The constant `true` if this is Java version 20 (also 20.x versions).
`static boolean`	`IS_JAVA_21` The constant `true` if this is Java version 21 (also 21.x versions).
`static boolean`	`IS_JAVA_22` The constant `true` if this is Java version 22 (also 22.x versions).
`static boolean`	`IS_JAVA_23` The constant `true` if this is Java version 23 (also 23.x versions).
`static boolean`	`IS_JAVA_24` The constant `true` if this is Java version 24 (also 24.x versions).
`static boolean`	`IS_JAVA_9` The constant `true` if this is Java version 9 (also 9.x versions).
`static boolean`	`IS_OS_400` The constant `true` if this is IBM OS/400.
`static boolean`	`IS_OS_AIX` The constant `true` if this is AIX.
`static boolean`	`IS_OS_ANDROID` The constant `true` if this is Android.
`static boolean`	`IS_OS_FREE_BSD` The constant `true` if this is FreeBSD.
`static boolean`	`IS_OS_HP_UX` The constant `true` if this is HP-UX.
`static boolean`	`IS_OS_IRIX` The constant `true` if this is Irix.
`static boolean`	`IS_OS_LINUX` The constant `true` if this is Linux.
`static boolean`	`IS_OS_MAC` The constant `true` if this is Mac.
`static boolean`	`IS_OS_MAC_OSX` The constant `true` if this is Mac.
`static boolean`	`IS_OS_MAC_OSX_BIG_SUR` The constant `true` if this is macOS X Big Sur.
`static boolean`	`IS_OS_MAC_OSX_CATALINA` The constant `true` if this is macOS X Catalina.
`static boolean`	`IS_OS_MAC_OSX_CHEETAH` The constant `true` if this is macOS X Cheetah.
`static boolean`	`IS_OS_MAC_OSX_EL_CAPITAN` The constant `true` if this is macOS X El Capitan.
`static boolean`	`IS_OS_MAC_OSX_HIGH_SIERRA` The constant `true` if this is macOS X High Sierra.
`static boolean`	`IS_OS_MAC_OSX_JAGUAR` The constant `true` if this is macOS X Jaguar.
`static boolean`	`IS_OS_MAC_OSX_LEOPARD` The constant `true` if this is macOS X Leopard.
`static boolean`	`IS_OS_MAC_OSX_LION` The constant `true` if this is macOS X Lion.
`static boolean`	`IS_OS_MAC_OSX_MAVERICKS` The constant `true` if this is macOS X Mavericks.
`static boolean`	`IS_OS_MAC_OSX_MOJAVE` The constant `true` if this is macOS X Mojave.
`static boolean`	`IS_OS_MAC_OSX_MONTEREY` The constant `true` if this is macOS X Monterey.
`static boolean`	`IS_OS_MAC_OSX_MOUNTAIN_LION` The constant `true` if this is macOS X Mountain Lion.
`static boolean`	`IS_OS_MAC_OSX_PANTHER` The constant `true` if this is macOS X Panther.
`static boolean`	`IS_OS_MAC_OSX_PUMA` The constant `true` if this is macOS X Puma.
`static boolean`	`IS_OS_MAC_OSX_SEQUOIA` The constant `true` if this is macOS X Sequoia.
`static boolean`	`IS_OS_MAC_OSX_SIERRA` The constant `true` if this is macOS X Sierra.
`static boolean`	`IS_OS_MAC_OSX_SNOW_LEOPARD` The constant `true` if this is macOS X Snow Leopard.
`static boolean`	`IS_OS_MAC_OSX_SONOMA` The constant `true` if this is macOS X Sonoma.
`static boolean`	`IS_OS_MAC_OSX_TIGER` The constant `true` if this is macOS X Tiger.
`static boolean`	`IS_OS_MAC_OSX_VENTURA` The constant `true` if this is macOS X Ventura.
`static boolean`	`IS_OS_MAC_OSX_YOSEMITE` The constant `true` if this is macOS X Yosemite.
`static boolean`	`IS_OS_NET_BSD` The constant `true` if this is NetBSD.
`static boolean`	`IS_OS_OPEN_BSD` The constant `true` if this is OpenBSD.
`static boolean`	`IS_OS_OS2` The constant `true` if this is OS/2.
`static boolean`	`IS_OS_SOLARIS` The constant `true` if this is Solaris.
`static boolean`	`IS_OS_SUN_OS` The constant `true` if this is SunOS.
`static boolean`	`IS_OS_UNIX` The constant `true` if this is a Unix like system, as in any of AIX, HP-UX, Irix, Linux, MacOSX, Solaris or SUN OS.
`static boolean`	`IS_OS_WINDOWS` The constant `true` if this is Windows.
`static boolean`	`IS_OS_WINDOWS_10` The constant `true` if this is Windows 10.
`static boolean`	`IS_OS_WINDOWS_11` The constant `true` if this is Windows 11.
`static boolean`	`IS_OS_WINDOWS_2000` The constant `true` if this is Windows 2000.
`static boolean`	`IS_OS_WINDOWS_2003` The constant `true` if this is Windows 2003.
`static boolean`	`IS_OS_WINDOWS_2008` The constant `true` if this is Windows Server 2008.
`static boolean`	`IS_OS_WINDOWS_2012` The constant `true` if this is Windows Server 2012.
`static boolean`	`IS_OS_WINDOWS_7` The constant `true` if this is Windows 7.
`static boolean`	`IS_OS_WINDOWS_8` The constant `true` if this is Windows 8.
`static boolean`	`IS_OS_WINDOWS_95` The constant `true` if this is Windows 95.
`static boolean`	`IS_OS_WINDOWS_98` The constant `true` if this is Windows 98.
`static boolean`	`IS_OS_WINDOWS_ME` The constant `true` if this is Windows ME.
`static boolean`	`IS_OS_WINDOWS_NT` The constant `true` if this is Windows NT.
`static boolean`	`IS_OS_WINDOWS_VISTA` The constant `true` if this is Windows Vista.
`static boolean`	`IS_OS_WINDOWS_XP` The constant `true` if this is Windows XP.
`static boolean`	`IS_OS_ZOS` The constant `true` if this is z/OS.
`static String`	`JAVA_AWT_FONTS` A constant for the System Property `java.awt.fonts`.
`static String`	`JAVA_AWT_GRAPHICSENV` A constant for the System Property `java.awt.graphicsenv`.
`static String`	`JAVA_AWT_HEADLESS` A constant for the System Property `java.awt.headless`.
`static String`	`JAVA_AWT_PRINTERJOB` A constant for the System Property `java.awt.printerjob`.
`static String`	`JAVA_CLASS_PATH` A constant for the System Property `java.class.path`.
`static String`	`JAVA_CLASS_VERSION` A constant for the System Property `java.class.version`.
`static String`	`JAVA_COMPILER` A constant for the System Property `java.compiler`.
`static String`	`JAVA_ENDORSED_DIRS` A constant for the System Property `java.endorsed.dirs`.
`static String`	`JAVA_EXT_DIRS` A constant for the System Property `java.ext.dirs`.
`static String`	`JAVA_HOME` A constant for the System Property `java.home`.
`static String`	`JAVA_HOME_KEY` Deprecated. Use `SystemProperties.JAVA_HOME`.
`static String`	`JAVA_IO_TMPDIR` A constant for the System Property `java.io.tmpdir`.
`static String`	`JAVA_IO_TMPDIR_KEY` Deprecated. Use `SystemProperties.JAVA_IO_TMPDIR`.
`static String`	`JAVA_LIBRARY_PATH` A constant for the System Property `java.library.path`.
`static String`	`JAVA_RUNTIME_NAME` A constant for the System Property `java.runtime.name`.
`static String`	`JAVA_RUNTIME_VERSION` A constant for the System Property `java.runtime.version`.
`static String`	`JAVA_SPECIFICATION_NAME` A constant for the System Property `java.specification.name`.
`static String`	`JAVA_SPECIFICATION_VENDOR` A constant for the System Property `java.specification.vendor`.
`static String`	`JAVA_SPECIFICATION_VERSION` A constant for the System Property `java.specification.version`.
`static String`	`JAVA_UTIL_PREFS_PREFERENCES_FACTORY` A constant for the System Property `java.util.prefs.PreferencesFactory`.
`static String`	`JAVA_VENDOR` A constant for the System Property `java.vendor`.
`static String`	`JAVA_VENDOR_URL` A constant for the System Property `java.vendor.url`.
`static String`	`JAVA_VERSION` A constant for the System Property `java.version`.
`static String`	`JAVA_VM_INFO` A constant for the System Property `java.vm.info`.
`static String`	`JAVA_VM_NAME` A constant for the System Property `java.vm.name`.
`static String`	`JAVA_VM_SPECIFICATION_NAME` A constant for the System Property `java.vm.specification.name`.
`static String`	`JAVA_VM_SPECIFICATION_VENDOR` A constant for the System Property `java.vm.specification.vendor`.
`static String`	`JAVA_VM_SPECIFICATION_VERSION` A constant for the System Property `java.vm.specification.version`.
`static String`	`JAVA_VM_VENDOR` A constant for the System Property `java.vm.vendor`.
`static String`	`JAVA_VM_VERSION` A constant for the System Property `java.vm.version`.
`static String`	`LINE_SEPARATOR` Deprecated. Use `System.lineSeparator()` instead, since it does not require a privilege check.
`static String`	`OS_ARCH` A constant for the System Property `os.arch`.
`static String`	`OS_NAME` A constant for the System Property `os.name`.
`static String`	`OS_VERSION` A constant for the System Property `os.version`.
`static String`	`PATH_SEPARATOR` Deprecated. Use `File.pathSeparator`, since it is guaranteed to be a string containing a single character and it does not require a privilege check.
`static String`	`USER_COUNTRY` A constant for the System Property `user.country` or `user.region`.
`static String`	`USER_DIR` A constant for the System Property `user.dir`.
`static String`	`USER_DIR_KEY` Deprecated. Use `SystemProperties.USER_DIR`.
`static String`	`USER_HOME` A constant for the System Property `user.home`.
`static String`	`USER_HOME_KEY` The System property key for the user home directory.
`static String`	`USER_LANGUAGE` A constant for the System Property `user.language`.
`static String`	`USER_NAME` A constant for the System Property `user.name`.
`static String`	`USER_NAME_KEY` Deprecated. Use `SystemProperties.USER_NAME`.
`static String`	`USER_TIMEZONE` A constant for the System Property `user.timezone`.

Constructor Summary

Constructors
Constructor and Description

SystemUtils()
SystemUtils instances shouldn't be constructed in standard programming.

Constructors
Constructor and Description
`SystemUtils()` SystemUtils instances shouldn't be constructed in standard programming.

Method Summary

All Methods Static Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`static String`	`getEnvironmentVariable(String name, String defaultValue)` Gets an environment variable, defaulting to `defaultValue` if the variable cannot be read.
`static String`	`getHostName()` Gets the host name from an environment variable (`COMPUTERNAME` on Windows, `HOSTNAME` elsewhere).
`static File`	`getJavaHome()` Gets the current Java home directory as a `File`.
`static Path`	`getJavaHomePath()` Gets the current Java home directory as a `File`.
`static File`	`getJavaIoTmpDir()` Gets the current Java IO temporary directory as a `File`.
`static Path`	`getJavaIoTmpDirPath()` Gets the current Java IO temporary directory as a `Path`.
`static File`	`getUserDir()` Gets the current user directory as a `File`.
`static Path`	`getUserDirPath()` Gets the current user directory as a `Path`.
`static File`	`getUserHome()` Gets the current user home directory as a `File`.
`static Path`	`getUserHomePath()` Gets the current user home directory as a `Path`.
`static String`	`getUserName()` Deprecated. Use `SystemProperties.getUserName()`.
`static String`	`getUserName(String defaultValue)` Deprecated. Use `SystemProperties.getUserName(String)`.
`static boolean`	`isJavaAwtHeadless()` Tests whether the `JAVA_AWT_HEADLESS` value is `true`.
`static boolean`	`isJavaVersionAtLeast(JavaVersion requiredVersion)` Tests whether the Java version at least the requested version.
`static boolean`	`isJavaVersionAtMost(JavaVersion requiredVersion)` Tests whether the Java version at most the requested version.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - FILE_ENCODING
```
public static final String FILE_ENCODING
```
    A constant for the System Property file.encoding.
    File encoding, such as Cp1252.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.0, Java 1.2
    
    See Also:
    
    SystemProperties.getFileEncoding()
  - FILE_SEPARATOR
```
@Deprecated
public static final String FILE_SEPARATOR
```
    Deprecated. Use File.separator, since it is guaranteed to be a string containing a single character and it does not require a privilege check.
    A constant for the System Property file.separator.
    The file separator is:
    - "/" on Unix
    - "\" on Windows.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getFileSeparator()
  - JAVA_AWT_FONTS
```
public static final String JAVA_AWT_FONTS
```
    A constant for the System Property java.awt.fonts.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1
    
    See Also:
    
    SystemProperties.getJavaAwtFonts()
  - JAVA_AWT_GRAPHICSENV
```
public static final String JAVA_AWT_GRAPHICSENV
```
    A constant for the System Property java.awt.graphicsenv.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1
    
    See Also:
    
    SystemProperties.getJavaAwtGraphicsenv()
  - JAVA_AWT_HEADLESS
```
public static final String JAVA_AWT_HEADLESS
```
    A constant for the System Property java.awt.headless. The value of this property is the String "true" or "false".
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1, Java 1.4
    
    See Also:
    
    isJavaAwtHeadless(), SystemProperties.getJavaAwtHeadless()
  - JAVA_AWT_PRINTERJOB
```
public static final String JAVA_AWT_PRINTERJOB
```
    A constant for the System Property java.awt.printerjob.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1
    
    See Also:
    
    SystemProperties.getJavaAwtPrinterjob()
  - JAVA_CLASS_PATH
```
public static final String JAVA_CLASS_PATH
```
    A constant for the System Property java.class.path. Java class path.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getJavaClassPath()
  - JAVA_CLASS_VERSION
```
public static final String JAVA_CLASS_VERSION
```
    A constant for the System Property java.class.version. Java class format version number.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getJavaClassVersion()
  - JAVA_COMPILER
```
public static final String JAVA_COMPILER
```
    A constant for the System Property java.compiler. Name of JIT compiler to use. First in JDK version 1.2. Not used in Sun JDKs after 1.2.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2. Not used in Sun versions after 1.2.
    
    See Also:
    
    SystemProperties.getJavaCompiler()
  - JAVA_ENDORSED_DIRS
```
public static final String JAVA_ENDORSED_DIRS
```
    A constant for the System Property java.endorsed.dirs. Path of endorsed directory or directories.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.4
    
    See Also:
    
    SystemProperties.getJavaEndorsedDirs()
  - JAVA_EXT_DIRS
```
public static final String JAVA_EXT_DIRS
```
    A constant for the System Property java.ext.dirs. Path of extension directory or directories.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.3
    
    See Also:
    
    SystemProperties.getJavaExtDirs()
  - JAVA_HOME
```
public static final String JAVA_HOME
```
    A constant for the System Property java.home. Java installation directory.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getJavaHome()
  - JAVA_IO_TMPDIR
```
public static final String JAVA_IO_TMPDIR
```
    A constant for the System Property java.io.tmpdir. Default temp file path.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
    
    See Also:
    
    SystemProperties.getJavaIoTmpdir()
  - JAVA_LIBRARY_PATH
```
public static final String JAVA_LIBRARY_PATH
```
    A constant for the System Property java.library.path. List of paths to search when loading libraries.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
    
    See Also:
    
    SystemProperties.getJavaLibraryPath()
  - JAVA_RUNTIME_NAME
```
public static final String JAVA_RUNTIME_NAME
```
    A constant for the System Property java.runtime.name. Java Runtime Environment name.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.0, Java 1.3
    
    See Also:
    
    SystemProperties.getJavaRuntimeName()
  - JAVA_RUNTIME_VERSION
```
public static final String JAVA_RUNTIME_VERSION
```
    A constant for the System Property java.runtime.version. Java Runtime Environment version.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.0, Java 1.3
    
    See Also:
    
    SystemProperties.getJavaRuntimeVersion()
  - JAVA_SPECIFICATION_NAME
```
public static final String JAVA_SPECIFICATION_NAME
```
    A constant for the System Property java.specification.name. Java Runtime Environment specification name.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
    
    See Also:
    
    SystemProperties.getJavaSpecificationName()
  - JAVA_SPECIFICATION_VENDOR
```
public static final String JAVA_SPECIFICATION_VENDOR
```
    A constant for the System Property java.specification.vendor. Java Runtime Environment specification vendor.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
    
    See Also:
    
    SystemProperties.getJavaSpecificationVendor()
  - JAVA_SPECIFICATION_VERSION
```
public static final String JAVA_SPECIFICATION_VERSION
```
    A constant for the System Property java.specification.version. Java Runtime Environment specification version.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.3
    
    See Also:
    
    SystemProperties.getJavaSpecificationVersion()
  - JAVA_UTIL_PREFS_PREFERENCES_FACTORY
```
public static final String JAVA_UTIL_PREFS_PREFERENCES_FACTORY
```
    A constant for the System Property java.util.prefs.PreferencesFactory. A class name.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1, Java 1.4
    
    See Also:
    
    SystemProperties.getJavaUtilPrefsPreferencesFactory()
  - JAVA_VENDOR
```
public static final String JAVA_VENDOR
```
    A constant for the System Property java.vendor. Java vendor-specific string.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getJavaVendor()
  - JAVA_VENDOR_URL
```
public static final String JAVA_VENDOR_URL
```
    A constant for the System Property java.vendor.url. Java vendor URL.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getJavaVendorUrl()
  - JAVA_VERSION
```
public static final String JAVA_VERSION
```
    A constant for the System Property java.version. Java version number.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getJavaVersion()
  - JAVA_VM_INFO
```
public static final String JAVA_VM_INFO
```
    A constant for the System Property java.vm.info. Java Virtual Machine implementation info.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.0, Java 1.2
    
    See Also:
    
    SystemProperties.getJavaVmInfo()
  - JAVA_VM_NAME
```
public static final String JAVA_VM_NAME
```
    A constant for the System Property java.vm.name. Java Virtual Machine implementation name.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
    
    See Also:
    
    SystemProperties.getJavaVmName()
  - JAVA_VM_SPECIFICATION_NAME
```
public static final String JAVA_VM_SPECIFICATION_NAME
```
    A constant for the System Property java.vm.specification.name. Java Virtual Machine specification name.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
    
    See Also:
    
    SystemProperties.getJavaVmSpecificationName()
  - JAVA_VM_SPECIFICATION_VENDOR
```
public static final String JAVA_VM_SPECIFICATION_VENDOR
```
    A constant for the System Property java.vm.specification.vendor. Java Virtual Machine specification vendor.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
    
    See Also:
    
    SystemProperties.getJavaVmSpecificationVendor()
  - JAVA_VM_SPECIFICATION_VERSION
```
public static final String JAVA_VM_SPECIFICATION_VERSION
```
    A constant for the System Property java.vm.specification.version. Java Virtual Machine specification version.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
    
    See Also:
    
    SystemProperties.getJavaVmSpecificationVersion()
  - JAVA_VM_VENDOR
```
public static final String JAVA_VM_VENDOR
```
    A constant for the System Property java.vm.vendor. Java Virtual Machine implementation vendor.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
    
    See Also:
    
    SystemProperties.getJavaVmVendor()
  - JAVA_VM_VERSION
```
public static final String JAVA_VM_VERSION
```
    A constant for the System Property java.vm.version. Java Virtual Machine implementation version.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.2
    
    See Also:
    
    SystemProperties.getJavaVmVersion()
  - LINE_SEPARATOR
```
@Deprecated
public static final String LINE_SEPARATOR
```
    Deprecated. Use System.lineSeparator() instead, since it does not require a privilege check.
    
    A constant for the System Property line.separator. Line separator ("\n" on Unix).
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getLineSeparator()
  - OS_ARCH
```
public static final String OS_ARCH
```
    A constant for the System Property os.arch. Operating system architecture.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getOsArch()
  - OS_NAME
```
public static final String OS_NAME
```
    A constant for the System Property os.name. Operating system name.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getOsName()
  - OS_VERSION
```
public static final String OS_VERSION
```
    A constant for the System Property os.version. Operating system version.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getOsVersion()
  - PATH_SEPARATOR
```
@Deprecated
public static final String PATH_SEPARATOR
```
    Deprecated. Use File.pathSeparator, since it is guaranteed to be a string containing a single character and it does not require a privilege check.
    
    A constant for the System Property path.separator. Path separator (":" on Unix).
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getPathSeparator()
  - USER_COUNTRY
```
public static final String USER_COUNTRY
```
    A constant for the System Property user.country or user.region. User's country code, such as "GB". First in Java version 1.2 as user.region. Renamed to user.country in 1.4
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.0, Java 1.2
  - USER_DIR
```
public static final String USER_DIR
```
    A constant for the System Property user.dir. User's current working directory.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getUserDir()
  - USER_HOME
```
public static final String USER_HOME
```
    A constant for the System Property user.home. User's home directory.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getUserHome()
  - USER_LANGUAGE
```
public static final String USER_LANGUAGE
```
    A constant for the System Property user.language. User's language code, such as "en".
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.0, Java 1.2
    
    See Also:
    
    SystemProperties.getUserLanguage()
  - USER_NAME
```
public static final String USER_NAME
```
    A constant for the System Property user.name. User's account name.
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    Java 1.1
    
    See Also:
    
    SystemProperties.getUserName()
  - USER_TIMEZONE
```
public static final String USER_TIMEZONE
```
    A constant for the System Property user.timezone. For example: "America/Los_Angeles".
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1
    
    See Also:
    
    SystemProperties.getUserTimezone()
  - IS_JAVA_1_1
```
public static final boolean IS_JAVA_1_1
```
    The constant true if this is Java version 1.1 (also 1.1.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
  - IS_JAVA_1_2
```
public static final boolean IS_JAVA_1_2
```
    The constant true if this is Java version 1.2 (also 1.2.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
  - IS_JAVA_1_3
```
public static final boolean IS_JAVA_1_3
```
    The constant true if this is Java version 1.3 (also 1.3.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
  - IS_JAVA_1_4
```
public static final boolean IS_JAVA_1_4
```
    The constant true if this is Java version 1.4 (also 1.4.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
  - IS_JAVA_1_5
```
public static final boolean IS_JAVA_1_5
```
    The constant true if this is Java version 1.5 (also 1.5.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
  - IS_JAVA_1_6
```
public static final boolean IS_JAVA_1_6
```
    The constant true if this is Java version 1.6 (also 1.6.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
  - IS_JAVA_1_7
```
public static final boolean IS_JAVA_1_7
```
    The constant true if this is Java version 1.7 (also 1.7.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.0
  - IS_JAVA_1_8
```
public static final boolean IS_JAVA_1_8
```
    The constant true if this is Java version 1.8 (also 1.8.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.3.2
  - IS_JAVA_1_9
```
@Deprecated
public static final boolean IS_JAVA_1_9
```
    Deprecated. As of release 3.5, replaced by IS_JAVA_9
    
    The constant true if this is Java version 1.9 (also 1.9.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_JAVA_9
```
public static final boolean IS_JAVA_9
```
    The constant true if this is Java version 9 (also 9.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.5
  - IS_JAVA_10
```
public static final boolean IS_JAVA_10
```
    The constant true if this is Java version 10 (also 10.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.7
  - IS_JAVA_11
```
public static final boolean IS_JAVA_11
```
    The constant true if this is Java version 11 (also 11.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.8
  - IS_JAVA_12
```
public static final boolean IS_JAVA_12
```
    The constant true if this is Java version 12 (also 12.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.9
  - IS_JAVA_13
```
public static final boolean IS_JAVA_13
```
    The constant true if this is Java version 13 (also 13.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.9
  - IS_JAVA_14
```
public static final boolean IS_JAVA_14
```
    The constant true if this is Java version 14 (also 14.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.10
  - IS_JAVA_15
```
public static final boolean IS_JAVA_15
```
    The constant true if this is Java version 15 (also 15.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.10
  - IS_JAVA_16
```
public static final boolean IS_JAVA_16
```
    The constant true if this is Java version 16 (also 16.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.13.0
  - IS_JAVA_17
```
public static final boolean IS_JAVA_17
```
    The constant true if this is Java version 17 (also 17.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.13.0
  - IS_JAVA_18
```
public static final boolean IS_JAVA_18
```
    The constant true if this is Java version 18 (also 18.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.13.0
  - IS_JAVA_19
```
public static final boolean IS_JAVA_19
```
    The constant true if this is Java version 19 (also 19.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.13.0
  - IS_JAVA_20
```
public static final boolean IS_JAVA_20
```
    The constant true if this is Java version 20 (also 20.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.13.0
  - IS_JAVA_21
```
public static final boolean IS_JAVA_21
```
    The constant true if this is Java version 21 (also 21.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.13.0
  - IS_JAVA_22
```
public static final boolean IS_JAVA_22
```
    The constant true if this is Java version 22 (also 22.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.15.0
  - IS_JAVA_23
```
public static final boolean IS_JAVA_23
```
    The constant true if this is Java version 23 (also 23.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.18.0
  - IS_JAVA_24
```
public static final boolean IS_JAVA_24
```
    The constant true if this is Java version 24 (also 24.x versions).
    The result depends on the value of the JAVA_SPECIFICATION_VERSION constant.
    
    The field will return false if JAVA_SPECIFICATION_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.18.0
  - IS_OS_AIX
```
public static final boolean IS_OS_AIX
```
    The constant true if this is AIX.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_ANDROID
```
public static final boolean IS_OS_ANDROID
```
    The constant true if this is Android.
    See https://developer.android.com/reference/java/lang/System#getProperties().
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.15.0
  - IS_OS_HP_UX
```
public static final boolean IS_OS_HP_UX
```
    The constant true if this is HP-UX.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_400
```
public static final boolean IS_OS_400
```
    The constant true if this is IBM OS/400.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.3
  - IS_OS_IRIX
```
public static final boolean IS_OS_IRIX
```
    The constant true if this is Irix.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_LINUX
```
public static final boolean IS_OS_LINUX
```
    The constant true if this is Linux.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_MAC
```
public static final boolean IS_OS_MAC
```
    The constant true if this is Mac.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_MAC_OSX
```
public static final boolean IS_OS_MAC_OSX
```
    The constant true if this is Mac.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_MAC_OSX_CHEETAH
```
public static final boolean IS_OS_MAC_OSX_CHEETAH
```
    The constant true if this is macOS X Cheetah.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_OS_MAC_OSX_PUMA
```
public static final boolean IS_OS_MAC_OSX_PUMA
```
    The constant true if this is macOS X Puma.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_OS_MAC_OSX_JAGUAR
```
public static final boolean IS_OS_MAC_OSX_JAGUAR
```
    The constant true if this is macOS X Jaguar.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_OS_MAC_OSX_PANTHER
```
public static final boolean IS_OS_MAC_OSX_PANTHER
```
    The constant true if this is macOS X Panther.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_OS_MAC_OSX_TIGER
```
public static final boolean IS_OS_MAC_OSX_TIGER
```
    The constant true if this is macOS X Tiger.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_OS_MAC_OSX_LEOPARD
```
public static final boolean IS_OS_MAC_OSX_LEOPARD
```
    The constant true if this is macOS X Leopard.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_OS_MAC_OSX_SNOW_LEOPARD
```
public static final boolean IS_OS_MAC_OSX_SNOW_LEOPARD
```
    The constant true if this is macOS X Snow Leopard.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_OS_MAC_OSX_LION
```
public static final boolean IS_OS_MAC_OSX_LION
```
    The constant true if this is macOS X Lion.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_OS_MAC_OSX_MOUNTAIN_LION
```
public static final boolean IS_OS_MAC_OSX_MOUNTAIN_LION
```
    The constant true if this is macOS X Mountain Lion.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_OS_MAC_OSX_MAVERICKS
```
public static final boolean IS_OS_MAC_OSX_MAVERICKS
```
    The constant true if this is macOS X Mavericks.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_OS_MAC_OSX_YOSEMITE
```
public static final boolean IS_OS_MAC_OSX_YOSEMITE
```
    The constant true if this is macOS X Yosemite.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_OS_MAC_OSX_EL_CAPITAN
```
public static final boolean IS_OS_MAC_OSX_EL_CAPITAN
```
    The constant true if this is macOS X El Capitan.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.5
  - IS_OS_MAC_OSX_SIERRA
```
public static final boolean IS_OS_MAC_OSX_SIERRA
```
    The constant true if this is macOS X Sierra.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.12.0
  - IS_OS_MAC_OSX_HIGH_SIERRA
```
public static final boolean IS_OS_MAC_OSX_HIGH_SIERRA
```
    The constant true if this is macOS X High Sierra.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.12.0
  - IS_OS_MAC_OSX_MOJAVE
```
public static final boolean IS_OS_MAC_OSX_MOJAVE
```
    The constant true if this is macOS X Mojave.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.12.0
  - IS_OS_MAC_OSX_CATALINA
```
public static final boolean IS_OS_MAC_OSX_CATALINA
```
    The constant true if this is macOS X Catalina.
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.12.0
  - IS_OS_MAC_OSX_BIG_SUR
```
public static final boolean IS_OS_MAC_OSX_BIG_SUR
```
    The constant true if this is macOS X Big Sur.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.12.0
  - IS_OS_MAC_OSX_MONTEREY
```
public static final boolean IS_OS_MAC_OSX_MONTEREY
```
    The constant true if this is macOS X Monterey.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.13.0
  - IS_OS_MAC_OSX_VENTURA
```
public static final boolean IS_OS_MAC_OSX_VENTURA
```
    The constant true if this is macOS X Ventura.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.13.0
  - IS_OS_MAC_OSX_SONOMA
```
public static final boolean IS_OS_MAC_OSX_SONOMA
```
    The constant true if this is macOS X Sonoma.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.15.0
  - IS_OS_MAC_OSX_SEQUOIA
```
public static final boolean IS_OS_MAC_OSX_SEQUOIA
```
    The constant true if this is macOS X Sequoia.
    The value depends on the value of the OS_NAME and OS_VERSION constants.
    
    The value is false if OS_NAME or OS_VERSION is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.18.0
  - IS_OS_FREE_BSD
```
public static final boolean IS_OS_FREE_BSD
```
    The constant true if this is FreeBSD.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.1
  - IS_OS_OPEN_BSD
```
public static final boolean IS_OS_OPEN_BSD
```
    The constant true if this is OpenBSD.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.1
  - IS_OS_NET_BSD
```
public static final boolean IS_OS_NET_BSD
```
    The constant true if this is NetBSD.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.1
  - IS_OS_OS2
```
public static final boolean IS_OS_OS2
```
    The constant true if this is OS/2.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_SOLARIS
```
public static final boolean IS_OS_SOLARIS
```
    The constant true if this is Solaris.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_SUN_OS
```
public static final boolean IS_OS_SUN_OS
```
    The constant true if this is SunOS.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_UNIX
```
public static final boolean IS_OS_UNIX
```
    The constant true if this is a Unix like system, as in any of AIX, HP-UX, Irix, Linux, MacOSX, Solaris or SUN OS.
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.1
  - IS_OS_WINDOWS
```
public static final boolean IS_OS_WINDOWS
```
    The constant true if this is Windows.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_2000
```
public static final boolean IS_OS_WINDOWS_2000
```
    The constant true if this is Windows 2000.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_2003
```
public static final boolean IS_OS_WINDOWS_2003
```
    The constant true if this is Windows 2003.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.1
  - IS_OS_WINDOWS_2008
```
public static final boolean IS_OS_WINDOWS_2008
```
    The constant true if this is Windows Server 2008.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.1
  - IS_OS_WINDOWS_2012
```
public static final boolean IS_OS_WINDOWS_2012
```
    The constant true if this is Windows Server 2012.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.4
  - IS_OS_WINDOWS_95
```
public static final boolean IS_OS_WINDOWS_95
```
    The constant true if this is Windows 95.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_98
```
public static final boolean IS_OS_WINDOWS_98
```
    The constant true if this is Windows 98.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_ME
```
public static final boolean IS_OS_WINDOWS_ME
```
    The constant true if this is Windows ME.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_NT
```
public static final boolean IS_OS_WINDOWS_NT
```
    The constant true if this is Windows NT.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_XP
```
public static final boolean IS_OS_WINDOWS_XP
```
    The constant true if this is Windows XP.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.0
  - IS_OS_WINDOWS_VISTA
```
public static final boolean IS_OS_WINDOWS_VISTA
```
    The constant true if this is Windows Vista.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    2.4
  - IS_OS_WINDOWS_7
```
public static final boolean IS_OS_WINDOWS_7
```
    The constant true if this is Windows 7.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.0
  - IS_OS_WINDOWS_8
```
public static final boolean IS_OS_WINDOWS_8
```
    The constant true if this is Windows 8.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.2
  - IS_OS_WINDOWS_10
```
public static final boolean IS_OS_WINDOWS_10
```
    The constant true if this is Windows 10.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.5
  - IS_OS_WINDOWS_11
```
public static final boolean IS_OS_WINDOWS_11
```
    The constant true if this is Windows 11.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    OpenJDK fixed the return value for os.name on Windows 11 to versions 8, 11, and 17:
    - Affects Java versions 7u321, 8u311, 11.0.13-oracle, 17.0.1: https://bugs.openjdk.org/browse/JDK-8274737
    - Fixed in OpenJDK commit https://github.com/openjdk/jdk/commit/97ea9dd2f24f9f1fb9b9345a4202a825ee28e014
    This value is initialized when the class is loaded.
    Since:
    
    3.13.0
  - IS_OS_ZOS
```
public static final boolean IS_OS_ZOS
```
    The constant true if this is z/OS.
    The result depends on the value of the OS_NAME constant.
    
    The field will return false if OS_NAME is null.
    
    This value is initialized when the class is loaded.
    
    Since:
    
    3.5
  - USER_HOME_KEY
```
public static final String USER_HOME_KEY
```
    The System property key for the user home directory.
    
    See Also:
    
    Constant Field Values
  - USER_NAME_KEY
```
@Deprecated
public static final String USER_NAME_KEY
```
    Deprecated. Use SystemProperties.USER_NAME.
    
    The System property key for the user name.
    
    See Also:
    
    Constant Field Values
  - USER_DIR_KEY
```
@Deprecated
public static final String USER_DIR_KEY
```
    Deprecated. Use SystemProperties.USER_DIR.
    
    The System property key for the user directory.
    
    See Also:
    
    Constant Field Values
  - JAVA_IO_TMPDIR_KEY
```
@Deprecated
public static final String JAVA_IO_TMPDIR_KEY
```
    Deprecated. Use SystemProperties.JAVA_IO_TMPDIR.
    
    The System property key for the Java IO temporary directory.
    
    See Also:
    
    Constant Field Values
  - JAVA_HOME_KEY
```
@Deprecated
public static final String JAVA_HOME_KEY
```
    Deprecated. Use SystemProperties.JAVA_HOME.
    
    The System property key for the Java home directory.
    
    See Also:
    
    Constant Field Values
  - AWT_TOOLKIT
```
public static final String AWT_TOOLKIT
```
    A constant for the System Property awt.toolkit.
    Holds a class name, on Windows XP this is sun.awt.windows.WToolkit.
    
    On platforms without a GUI, this value is null.
    
    Defaults to null if the runtime does not have security access to read this property or the property does not exist.
    
    This value is initialized when the class is loaded. If System.setProperty(String,String) or System.setProperties(java.util.Properties) is called after this class is loaded, the value will be out of sync with that System property.
    
    Since:
    
    2.1
    
    See Also:
    
    SystemProperties.getAwtToolkit()
- Constructor Detail
  - SystemUtils
```
public SystemUtils()
```
    SystemUtils instances shouldn't be constructed in standard programming. Instead, elements should be accessed directly, for example SystemUtils.FILE_SEPARATOR.
    This constructor is public to permit tools that require a JavaBean instance to operate.
- Method Detail
  - getEnvironmentVariable
```
public static String getEnvironmentVariable(String name,
                                            String defaultValue)
```
    Gets an environment variable, defaulting to defaultValue if the variable cannot be read.
    If a SecurityException is caught, the return value is defaultValue and a message is written to System.err.
    
    Parameters:
    
    name - the environment variable name.
    
    defaultValue - the default value.
    
    Returns:
    
    the environment variable value or defaultValue if a security problem occurs.
    
    Since:
    
    3.8
  - getHostName
```
public static String getHostName()
```
    Gets the host name from an environment variable (COMPUTERNAME on Windows, HOSTNAME elsewhere).
    If you want to know what the network stack says is the host name, you should use InetAddress.getLocalHost().getHostName().
    
    Returns:
    
    the host name. Will be null if the environment variable is not defined.
    
    Since:
    
    3.6
  - getJavaHome
```
public static File getJavaHome()
```
    Gets the current Java home directory as a File.
    
    Returns:
    
    a directory.
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    2.1
    
    See Also:
    
    SystemProperties.getJavaHome()
  - getJavaHomePath
```
public static Path getJavaHomePath()
```
    Gets the current Java home directory as a File.
    
    Returns:
    
    a directory.
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    3.18.0
    
    See Also:
    
    SystemProperties.getJavaHome()
  - getJavaIoTmpDir
```
public static File getJavaIoTmpDir()
```
    Gets the current Java IO temporary directory as a File.
    
    Returns:
    
    a directory.
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    2.1
    
    See Also:
    
    SystemProperties.getJavaIoTmpdir()
  - getJavaIoTmpDirPath
```
public static Path getJavaIoTmpDirPath()
```
    Gets the current Java IO temporary directory as a Path.
    
    Returns:
    
    a directory.
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    3.18.0
    
    See Also:
    
    SystemProperties.getJavaIoTmpdir()
  - getUserDir
```
public static File getUserDir()
```
    Gets the current user directory as a File.
    The result is based on the system property .
    
    Returns:
    
    a directory.
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    2.1
    
    See Also:
    
    SystemProperties.getUserDir()
  - getUserDirPath
```
public static Path getUserDirPath()
```
    Gets the current user directory as a Path.
    The result is based on the system property .
    
    Returns:
    
    a directory.
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    3.18.0
    
    See Also:
    
    SystemProperties.getUserDir()
  - getUserHome
```
public static File getUserHome()
```
    Gets the current user home directory as a File.
    The result is based on the system property .
    
    Returns:
    
    a directory.
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    2.1
    
    See Also:
    
    SystemProperties.getUserHome()
  - getUserHomePath
```
public static Path getUserHomePath()
```
    Gets the current user home directory as a Path.
    The result is based on the system property .
    
    Returns:
    
    a directory.
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    3.18.0
    
    See Also:
    
    SystemProperties.getUserHome()
  - getUserName
```
@Deprecated
public static String getUserName()
```
    Deprecated. Use SystemProperties.getUserName().
    
    Gets the current user name.
    The result is based on the system property .
    
    Returns:
    
    a name.
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    3.10
    
    See Also:
    
    SystemProperties.getUserName()
  - getUserName
```
@Deprecated
public static String getUserName(String defaultValue)
```
    Deprecated. Use SystemProperties.getUserName(String).
    
    Gets the user name.
    The result is based on the system property .
    
    Parameters:
    
    defaultValue - A default value.
    
    Returns:
    
    a name.
    
    Throws:
    
    SecurityException - if a security manager exists and its checkPropertyAccess method doesn't allow access to the specified system property.
    
    Since:
    
    3.10
    
    See Also:
    
    SystemProperties.getUserName()
  - isJavaAwtHeadless
```
public static boolean isJavaAwtHeadless()
```
    Tests whether the JAVA_AWT_HEADLESS value is true.
    The result is based on the system property .
    
    Returns:
    
    true if JAVA_AWT_HEADLESS is "true", false otherwise.
    
    Since:
    
    2.1, Java 1.4
    
    See Also:
    
    JAVA_AWT_HEADLESS
  - isJavaVersionAtLeast
```
public static boolean isJavaVersionAtLeast(JavaVersion requiredVersion)
```
    Tests whether the Java version at least the requested version.
    The result is based on the system property saved in JAVA_SPECIFICATION_VERSION.
    
    Parameters:
    
    requiredVersion - the required version, for example 1.31f.
    
    Returns:
    
    true if the actual version is equal or greater than the required version.
  - isJavaVersionAtMost
```
public static boolean isJavaVersionAtMost(JavaVersion requiredVersion)
```
    Tests whether the Java version at most the requested version.
    The result is based on the system property saved in JAVA_SPECIFICATION_VERSION.
    
    Parameters:
    
    requiredVersion - the required version, for example 1.31f.
    
    Returns:
    
    true if the actual version is equal or less than the required version.
    
    Since:
    
    3.9

Class SystemUtils

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

FILE_ENCODING

FILE_SEPARATOR

JAVA_AWT_FONTS

JAVA_AWT_GRAPHICSENV

JAVA_AWT_HEADLESS

JAVA_AWT_PRINTERJOB

JAVA_CLASS_PATH

JAVA_CLASS_VERSION

JAVA_COMPILER

JAVA_ENDORSED_DIRS

JAVA_EXT_DIRS

JAVA_HOME

JAVA_IO_TMPDIR

JAVA_LIBRARY_PATH

JAVA_RUNTIME_NAME

JAVA_RUNTIME_VERSION

JAVA_SPECIFICATION_NAME

JAVA_SPECIFICATION_VENDOR

JAVA_SPECIFICATION_VERSION

JAVA_UTIL_PREFS_PREFERENCES_FACTORY

JAVA_VENDOR

JAVA_VENDOR_URL

JAVA_VERSION

JAVA_VM_INFO

JAVA_VM_NAME

JAVA_VM_SPECIFICATION_NAME

JAVA_VM_SPECIFICATION_VENDOR

JAVA_VM_SPECIFICATION_VERSION

JAVA_VM_VENDOR

JAVA_VM_VERSION

LINE_SEPARATOR

OS_ARCH

OS_NAME

OS_VERSION

PATH_SEPARATOR

USER_COUNTRY

USER_DIR

USER_HOME

USER_LANGUAGE

USER_NAME

USER_TIMEZONE

IS_JAVA_1_1

IS_JAVA_1_2

IS_JAVA_1_3

IS_JAVA_1_4

IS_JAVA_1_5

IS_JAVA_1_6

IS_JAVA_1_7

IS_JAVA_1_8

IS_JAVA_1_9

IS_JAVA_9

IS_JAVA_10

IS_JAVA_11

IS_JAVA_12

IS_JAVA_13

IS_JAVA_14

IS_JAVA_15

IS_JAVA_16

IS_JAVA_17

IS_JAVA_18

IS_JAVA_19

IS_JAVA_20

IS_JAVA_21

IS_JAVA_22

IS_JAVA_23

IS_JAVA_24

IS_OS_AIX

IS_OS_ANDROID

IS_OS_HP_UX

IS_OS_400

IS_OS_IRIX

IS_OS_LINUX

IS_OS_MAC

IS_OS_MAC_OSX