org.apache.commons.lang3.exception

Class ExceptionUtils

java.lang.Object

org.apache.commons.lang3.exception.ExceptionUtils

public class ExceptionUtils
extends Object

Provides utilities for manipulating and examining Throwable objects.

Since:

1.0

Constructor Summary

Constructors

Constructor and Description
ExceptionUtils() Deprecated. TODO Make private in 4.0.

Method Summary

Modifier and Type	Method and Description
static <T extends RuntimeException> T	asRuntimeException(Throwable throwable) Throws the given (usually checked) exception without adding the exception to the throws clause of the calling method.
static void	forEach(Throwable throwable, Consumer<Throwable> consumer) Performs an action for each Throwable causes of the given Throwable.
static Throwable	getCause(Throwable throwable) Deprecated. This feature will be removed in Lang 4, use Throwable.getCause() instead
static Throwable	getCause(Throwable throwable, String[] methodNames) Deprecated. This feature will be removed in Lang 4, use Throwable.getCause() instead
static String[]	getDefaultCauseMethodNames() Deprecated. This feature will be removed in Lang 4
static String	getMessage(Throwable th) Gets a short message summarizing the exception.
static Throwable	getRootCause(Throwable throwable) Walks the Throwable to obtain its root cause.
static String	getRootCauseMessage(Throwable throwable) Gets a short message summarizing the root cause exception.
static String[]	getRootCauseStackTrace(Throwable throwable) Gets a compact stack trace for the root cause of the supplied Throwable.
static List<String>	getRootCauseStackTraceList(Throwable throwable) Gets a compact stack trace for the root cause of the supplied Throwable.
static String[]	getStackFrames(Throwable throwable) Gets the stack trace associated with the specified Throwable object, decomposing it into a list of stack frames.
static String	getStackTrace(Throwable throwable) Gets the stack trace from a Throwable as a String, including suppressed and cause exceptions.
static int	getThrowableCount(Throwable throwable) Gets a count of the number of Throwable objects in the exception chain.
static List<Throwable>	getThrowableList(Throwable throwable) Gets the list of Throwable objects in the exception chain.
static Throwable[]	getThrowables(Throwable throwable) Gets the list of Throwable objects in the exception chain.
static boolean	hasCause(Throwable chain, Class<? extends Throwable> type) Tests if the throwable's causal chain have an immediate or wrapped exception of the given type?
static int	indexOfThrowable(Throwable throwable, Class<? extends Throwable> clazz) Returns the (zero-based) index of the first Throwable that matches the specified class (exactly) in the exception chain.
static int	indexOfThrowable(Throwable throwable, Class<? extends Throwable> clazz, int fromIndex) Returns the (zero-based) index of the first Throwable that matches the specified type in the exception chain from a specified index.
static int	indexOfType(Throwable throwable, Class<? extends Throwable> type) Returns the (zero-based) index of the first Throwable that matches the specified class or subclass in the exception chain.
static int	indexOfType(Throwable throwable, Class<? extends Throwable> type, int fromIndex) Returns the (zero-based) index of the first Throwable that matches the specified type in the exception chain from a specified index.
static boolean	isChecked(Throwable throwable) Checks if a throwable represents a checked exception
static boolean	isUnchecked(Throwable throwable) Checks if a throwable represents an unchecked exception
static void	printRootCauseStackTrace(Throwable throwable) Prints a compact stack trace for the root cause of a throwable to System.err.
static void	printRootCauseStackTrace(Throwable throwable, PrintStream printStream) Prints a compact stack trace for the root cause of a throwable.
static void	printRootCauseStackTrace(Throwable throwable, PrintWriter printWriter) Prints a compact stack trace for the root cause of a throwable.
static void	removeCommonFrames(List<String> causeFrames, List<String> wrapperFrames) Removes common frames from the cause trace given the two stack traces.
static <T> T	rethrow(Throwable throwable) Throws the given (usually checked) exception without adding the exception to the throws clause of the calling method.
static Stream<Throwable>	stream(Throwable throwable) Streams causes of a Throwable.
static <T extends Throwable> T	throwableOfThrowable(Throwable throwable, Class<T> clazz) Returns the first Throwable that matches the specified class (exactly) in the exception chain.
static <T extends Throwable> T	throwableOfThrowable(Throwable throwable, Class<T> clazz, int fromIndex) Returns the first Throwable that matches the specified type in the exception chain from a specified index.
static <T extends Throwable> T	throwableOfType(Throwable throwable, Class<T> type) Returns the throwable of the first Throwable that matches the specified class or subclass in the exception chain.
static <T extends Throwable> T	throwableOfType(Throwable throwable, Class<T> type, int fromIndex) Returns the first Throwable that matches the specified type in the exception chain from a specified index.
static <T> T	throwUnchecked(T throwable) Deprecated. Use throwUnchecked(Throwable).
static <T extends Throwable> T	throwUnchecked(T throwable) Tests whether the specified Throwable is unchecked and throws it if so.
static <R> R	wrapAndThrow(Throwable throwable) Throws a checked exception without adding the exception to the throws clause of the calling method.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ExceptionUtils

@Deprecated
public ExceptionUtils()

Deprecated. TODO Make private in 4.0.

Public constructor allows an instance of ExceptionUtils to be created, although that is not normally necessary.

Method Detail

asRuntimeException

public static <T extends RuntimeException> T asRuntimeException(Throwable throwable)

Throws the given (usually checked) exception without adding the exception to the throws clause of the calling method. This method prevents throws clause inflation and reduces the clutter of "Caused by" exceptions in the stack trace.

The use of this technique may be controversial, but useful.

  // There is no throws clause in the method signature.
  public int propagateExample {
      try {
          // Throws IOException
          invocation();
      } catch (Exception e) {
          // Propagates a checked exception.
          throw ExceptionUtils.asRuntimeException(e);
      }
      // more processing
      ...
      return value;
  }
 

This is an alternative to the more conservative approach of wrapping the checked exception in a RuntimeException:

  // There is no throws clause in the method signature.
  public int wrapExample() {
      try {
          // throws IOException.
          invocation();
      } catch (Error e) {
          throw e;
      } catch (RuntimeException e) {
          // Throws an unchecked exception.
          throw e;
      } catch (Exception e) {
          // Wraps a checked exception.
          throw new UndeclaredThrowableException(e);
      }
      // more processing
      ...
      return value;
  }
 

One downside to using this approach is that the Java compiler will not allow invoking code to specify a checked exception in a catch clause unless there is some code path within the try block that has invoked a method declared with that checked exception. If the invoking site wishes to catch the shaded checked exception, it must either invoke the shaded code through a method re-declaring the desired checked exception, or catch Exception and use the instanceof operator. Either of these techniques are required when interacting with non-Java JVM code such as Jython, Scala, or Groovy, since these languages do not consider any exceptions as checked.

Type Parameters:

T - The type of the returned value.

Parameters:

throwable - The throwable to rethrow.

Returns:

Never actually returned, this generic type matches any type which the calling site requires. "Returning" the results of this method, as done in the propagateExample above, will satisfy the Java compiler requirement that all code paths return a value.

Since:

3.14.0

See Also:

wrapAndThrow(Throwable)

forEach

public static void forEach(Throwable throwable,
                           Consumer<Throwable> consumer)

Performs an action for each Throwable causes of the given Throwable.

A throwable without cause will return a stream containing one element - the input throwable. A throwable with one cause will return a stream containing two elements. - the input throwable and the cause throwable. A null throwable will return a stream of count zero.

This method handles recursive cause structures that might otherwise cause infinite loops. The cause chain is processed until the end is reached, or until the next item in the chain is already in the result set.

Parameters:

throwable - The Throwable to traverse.

consumer - a non-interfering action to perform on the elements.

Since:

3.13.0

getCause

@Deprecated
public static Throwable getCause(Throwable throwable)

Deprecated. This feature will be removed in Lang 4, use Throwable.getCause() instead

Introspects the Throwable to obtain the cause.

The method searches for methods with specific names that return a Throwable object. This will pick up most wrapping exceptions, including those from JDK 1.4.

The default list searched for are:

• getCause()
• getNextException()
• getTargetException()
• getException()
• getSourceException()
• getRootCause()
• getCausedByException()
• getNested()

If none of the above is found, returns null.

Parameters:

throwable - the throwable to introspect for a cause, may be null

Returns:

the cause of the Throwable, null if none found or null throwable input

Since:

1.0

getCause

@Deprecated
public static Throwable getCause(Throwable throwable,
                                             String[] methodNames)

Deprecated. This feature will be removed in Lang 4, use Throwable.getCause() instead

Introspects the Throwable to obtain the cause.

A null set of method names means use the default set. A null in the set of method names will be ignored.

Parameters:

throwable - the throwable to introspect for a cause, may be null

methodNames - the method names, null treated as default set

Returns:

the cause of the Throwable, null if none found or null throwable input

Since:

1.0

getDefaultCauseMethodNames

@Deprecated
public static String[] getDefaultCauseMethodNames()

Deprecated. This feature will be removed in Lang 4

Gets the default names used when searching for the cause of an exception.

This may be modified and used in the overloaded getCause(Throwable, String[]) method.

Returns:

cloned array of the default method names

Since:

3.0

getMessage

public static String getMessage(Throwable th)

Gets a short message summarizing the exception.

The message returned is of the form {ClassNameWithoutPackage}: {ThrowableMessage}

Parameters:

th - the throwable to get a message for, null returns empty string

Returns:

the message, non-null

Since:

2.2

getRootCause

public static Throwable getRootCause(Throwable throwable)

Walks the Throwable to obtain its root cause.

This method walks through the exception chain until the last element, the root cause of the chain, using Throwable.getCause(), and returns that exception.

This method handles recursive cause chains that might otherwise cause infinite loops. The cause chain is processed until the end, or until the next item in the chain is already processed. If we detect a loop, then return the element before the loop.

Parameters:

throwable - the throwable to get the root cause for, may be null

Returns:

the root cause of the Throwable, null if null throwable input

getRootCauseMessage

public static String getRootCauseMessage(Throwable throwable)

Gets a short message summarizing the root cause exception.

The message returned is of the form {ClassNameWithoutPackage}: {ThrowableMessage}

Parameters:

throwable - the throwable to get a message for, null returns empty string

Returns:

the message, non-null

Since:

2.2

getRootCauseStackTrace

public static String[] getRootCauseStackTrace(Throwable throwable)

Gets a compact stack trace for the root cause of the supplied Throwable.

The output of this method is consistent across JDK versions. It consists of the root exception followed by each of its wrapping exceptions separated by '[wrapped]'. Note that this is the opposite order to the JDK1.4 display.

Parameters:

throwable - the throwable to examine, may be null

Returns:

an array of stack trace frames, never null

Since:

2.0

getRootCauseStackTraceList

public static List<String> getRootCauseStackTraceList(Throwable throwable)

Gets a compact stack trace for the root cause of the supplied Throwable.

The output of this method is consistent across JDK versions. It consists of the root exception followed by each of its wrapping exceptions separated by '[wrapped]'. Note that this is the opposite order to the JDK1.4 display.

Parameters:

throwable - the throwable to examine, may be null

Returns:

a list of stack trace frames, never null

Since:

3.13.0

getStackFrames

public static String[] getStackFrames(Throwable throwable)

Gets the stack trace associated with the specified Throwable object, decomposing it into a list of stack frames.

The result of this method vary by JDK version as this method uses Throwable.printStackTrace(java.io.PrintWriter).

Parameters:

throwable - the Throwable to examine, may be null

Returns:

an array of strings describing each stack frame, never null

getStackTrace

public static String getStackTrace(Throwable throwable)

Gets the stack trace from a Throwable as a String, including suppressed and cause exceptions.

The result of this method vary by JDK version as this method uses Throwable.printStackTrace(java.io.PrintWriter).

Parameters:

throwable - the Throwable to be examined, may be null

Returns:

the stack trace as generated by the exception's printStackTrace(PrintWriter) method, or an empty String if null input

getThrowableCount

public static int getThrowableCount(Throwable throwable)

Gets a count of the number of Throwable objects in the exception chain.

A throwable without cause will return 1. A throwable with one cause will return 2 and so on. A null throwable will return 0.

This method handles recursive cause chains that might otherwise cause infinite loops. The cause chain is processed until the end, or until the next item in the chain is already in the result.

Parameters:

throwable - the throwable to inspect, may be null

Returns:

the count of throwables, zero on null input

getThrowableList

public static List<Throwable> getThrowableList(Throwable throwable)

Gets the list of Throwable objects in the exception chain.

A throwable without cause will return a list containing one element - the input throwable. A throwable with one cause will return a list containing two elements. - the input throwable and the cause throwable. A null throwable will return a list of size zero.

This method handles recursive cause chains that might otherwise cause infinite loops. The cause chain is processed until the end, or until the next item in the chain is already in the result list.

Parameters:

throwable - the throwable to inspect, may be null

Returns:

the list of throwables, never null

Since:

2.2

getThrowables

public static Throwable[] getThrowables(Throwable throwable)

Gets the list of Throwable objects in the exception chain.

A throwable without cause will return an array containing one element - the input throwable. A throwable with one cause will return an array containing two elements. - the input throwable and the cause throwable. A null throwable will return an array of size zero.

This method handles recursive cause chains that might otherwise cause infinite loops. The cause chain is processed until the end, or until the next item in the chain is already in the result array.

Parameters:

throwable - the throwable to inspect, may be null

Returns:

the array of throwables, never null

See Also:

getThrowableList(Throwable)

hasCause

public static boolean hasCause(Throwable chain,
                               Class<? extends Throwable> type)

Tests if the throwable's causal chain have an immediate or wrapped exception of the given type?

Parameters:

chain - The root of a Throwable causal chain.

type - The exception type to test.

Returns:

true, if chain is an instance of type or is an UndeclaredThrowableException wrapping a cause.

Since:

3.5

See Also:

wrapAndThrow(Throwable)

indexOfThrowable

public static int indexOfThrowable(Throwable throwable,
                                   Class<? extends Throwable> clazz)

Returns the (zero-based) index of the first Throwable that matches the specified class (exactly) in the exception chain. Subclasses of the specified class do not match - see indexOfType(Throwable, Class) for the opposite.

A null throwable returns -1. A null type returns -1. No match in the chain returns -1.

Parameters:

throwable - the throwable to inspect, may be null

clazz - the class to search for, subclasses do not match, null returns -1

Returns:

the index into the throwable chain, -1 if no match or null input

indexOfThrowable

public static int indexOfThrowable(Throwable throwable,
                                   Class<? extends Throwable> clazz,
                                   int fromIndex)

Returns the (zero-based) index of the first Throwable that matches the specified type in the exception chain from a specified index. Subclasses of the specified class do not match - see indexOfType(Throwable, Class, int) for the opposite.

A null throwable returns -1. A null type returns -1. No match in the chain returns -1. A negative start index is treated as zero. A start index greater than the number of throwables returns -1.

Parameters:

throwable - the throwable to inspect, may be null

clazz - the class to search for, subclasses do not match, null returns -1

fromIndex - the (zero-based) index of the starting position, negative treated as zero, larger than chain size returns -1

Returns:

the index into the throwable chain, -1 if no match or null input

indexOfType

public static int indexOfType(Throwable throwable,
                              Class<? extends Throwable> type)

Returns the (zero-based) index of the first Throwable that matches the specified class or subclass in the exception chain. Subclasses of the specified class do match - see indexOfThrowable(Throwable, Class) for the opposite.

A null throwable returns -1. A null type returns -1. No match in the chain returns -1.

Parameters:

throwable - the throwable to inspect, may be null

type - the type to search for, subclasses match, null returns -1

Returns:

the index into the throwable chain, -1 if no match or null input

Since:

2.1

indexOfType

public static int indexOfType(Throwable throwable,
                              Class<? extends Throwable> type,
                              int fromIndex)

Returns the (zero-based) index of the first Throwable that matches the specified type in the exception chain from a specified index. Subclasses of the specified class do match - see indexOfThrowable(Throwable, Class) for the opposite.

A null throwable returns -1. A null type returns -1. No match in the chain returns -1. A negative start index is treated as zero. A start index greater than the number of throwables returns -1.

Parameters:

throwable - the throwable to inspect, may be null

type - the type to search for, subclasses match, null returns -1

fromIndex - the (zero-based) index of the starting position, negative treated as zero, larger than chain size returns -1

Returns:

the index into the throwable chain, -1 if no match or null input

Since:

2.1

isChecked

public static boolean isChecked(Throwable throwable)

Checks if a throwable represents a checked exception

Parameters:

throwable - The throwable to check.

Returns:

True if the given Throwable is a checked exception.

Since:

3.13.0

isUnchecked

public static boolean isUnchecked(Throwable throwable)

Checks if a throwable represents an unchecked exception

Parameters:

throwable - The throwable to check.

Returns:

True if the given Throwable is an unchecked exception.

Since:

3.13.0

printRootCauseStackTrace

public static void printRootCauseStackTrace(Throwable throwable)

Prints a compact stack trace for the root cause of a throwable to System.err.

The compact stack trace starts with the root cause and prints stack frames up to the place where it was caught and wrapped. Then it prints the wrapped exception and continues with stack frames until the wrapper exception is caught and wrapped again, etc.

The output of this method is consistent across JDK versions.

The method is equivalent to printStackTrace for throwables that don't have nested causes.

Parameters:

throwable - the throwable to output

Since:

2.0

printRootCauseStackTrace

public static void printRootCauseStackTrace(Throwable throwable,
                                            PrintStream printStream)

Prints a compact stack trace for the root cause of a throwable.

The compact stack trace starts with the root cause and prints stack frames up to the place where it was caught and wrapped. Then it prints the wrapped exception and continues with stack frames until the wrapper exception is caught and wrapped again, etc.

The output of this method is consistent across JDK versions. Note that this is the opposite order to the JDK1.4 display.

The method is equivalent to printStackTrace for throwables that don't have nested causes.

Parameters:

throwable - the throwable to output, may be null

printStream - the stream to output to, may not be null

Throws:

NullPointerException - if the printStream is null

Since:

2.0

printRootCauseStackTrace

public static void printRootCauseStackTrace(Throwable throwable,
                                            PrintWriter printWriter)

Prints a compact stack trace for the root cause of a throwable.

The compact stack trace starts with the root cause and prints stack frames up to the place where it was caught and wrapped. Then it prints the wrapped exception and continues with stack frames until the wrapper exception is caught and wrapped again, etc.

The output of this method is consistent across JDK versions. Note that this is the opposite order to the JDK1.4 display.

The method is equivalent to printStackTrace for throwables that don't have nested causes.

Parameters:

throwable - the throwable to output, may be null

printWriter - the writer to output to, may not be null

Throws:

NullPointerException - if the printWriter is null

Since:

2.0

removeCommonFrames

public static void removeCommonFrames(List<String> causeFrames,
                                      List<String> wrapperFrames)

Removes common frames from the cause trace given the two stack traces.

Parameters:

causeFrames - stack trace of a cause throwable

wrapperFrames - stack trace of a wrapper throwable

Throws:

NullPointerException - if either argument is null

Since:

2.0

rethrow

public static <T> T rethrow(Throwable throwable)

Throws the given (usually checked) exception without adding the exception to the throws clause of the calling method. This method prevents throws clause inflation and reduces the clutter of "Caused by" exceptions in the stack trace.

The use of this technique may be controversial, but useful.

  // There is no throws clause in the method signature.
  public int propagateExample() {
      try {
          // throws SomeCheckedException.
          return invocation();
      } catch (SomeCheckedException e) {
          // Propagates a checked exception and compiles to return an int.
          return ExceptionUtils.rethrow(e);
      }
  }
 

This is an alternative to the more conservative approach of wrapping the checked exception in a RuntimeException:

  // There is no throws clause in the method signature.
  public int wrapExample() {
      try {
          // throws IOException.
          return invocation();
      } catch (Error e) {
          throw e;
      } catch (RuntimeException e) {
          // Throws an unchecked exception.
          throw e;
      } catch (Exception e) {
          // wraps a checked exception.
          throw new UndeclaredThrowableException(e);
      }
  }
 

One downside to using this approach is that the Java compiler will not allow invoking code to specify a checked exception in a catch clause unless there is some code path within the try block that has invoked a method declared with that checked exception. If the invoking site wishes to catch the shaded checked exception, it must either invoke the shaded code through a method re-declaring the desired checked exception, or catch Exception and use the instanceof operator. Either of these techniques are required when interacting with non-Java JVM code such as Jython, Scala, or Groovy, since these languages do not consider any exceptions as checked.

Type Parameters:

T - The type of the return value.

Parameters:

throwable - The throwable to rethrow.

Returns:

Never actually returns, this generic type matches any type which the calling site requires. "Returning" the results of this method, as done in the propagateExample above, will satisfy the Java compiler requirement that all code paths return a value.

Since:

3.5

See Also:

wrapAndThrow(Throwable)

stream

public static Stream<Throwable> stream(Throwable throwable)

Streams causes of a Throwable.

A throwable without cause will return a stream containing one element - the input throwable. A throwable with one cause will return a stream containing two elements. - the input throwable and the cause throwable. A null throwable will return a stream of count zero.

This method handles recursive cause chains that might otherwise cause infinite loops. The cause chain is processed until the end, or until the next item in the chain is already in the result.

Parameters:

throwable - The Throwable to traverse

Returns:

A new Stream of Throwable causes.

Since:

3.13.0

throwableOfThrowable

public static <T extends Throwable> T throwableOfThrowable(Throwable throwable,
                                                           Class<T> clazz)

Returns the first Throwable that matches the specified class (exactly) in the exception chain. Subclasses of the specified class do not match - see throwableOfType(Throwable, Class) for the opposite.

A null throwable returns null. A null type returns null. No match in the chain returns null.

Type Parameters:

T - the type of Throwable you are searching.

Parameters:

throwable - the throwable to inspect, may be null

clazz - the class to search for, subclasses do not match, null returns null

Returns:

the first matching throwable from the throwable chain, null if no match or null input

Since:

3.10

throwableOfThrowable

public static <T extends Throwable> T throwableOfThrowable(Throwable throwable,
                                                           Class<T> clazz,
                                                           int fromIndex)

Returns the first Throwable that matches the specified type in the exception chain from a specified index. Subclasses of the specified class do not match - see throwableOfType(Throwable, Class, int) for the opposite.

A null throwable returns null. A null type returns null. No match in the chain returns null. A negative start index is treated as zero. A start index greater than the number of throwables returns null.

Type Parameters:

T - the type of Throwable you are searching.

Parameters:

throwable - the throwable to inspect, may be null

clazz - the class to search for, subclasses do not match, null returns null

fromIndex - the (zero-based) index of the starting position, negative treated as zero, larger than chain size returns null

Returns:

the first matching throwable from the throwable chain, null if no match or null input

Since:

3.10

throwableOfType

public static <T extends Throwable> T throwableOfType(Throwable throwable,
                                                      Class<T> type)

Returns the throwable of the first Throwable that matches the specified class or subclass in the exception chain. Subclasses of the specified class do match - see throwableOfThrowable(Throwable, Class) for the opposite.

A null throwable returns null. A null type returns null. No match in the chain returns null.

Type Parameters:

T - the type of Throwable you are searching.

Parameters:

throwable - the throwable to inspect, may be null

type - the type to search for, subclasses match, null returns null

Returns:

the first matching throwable from the throwable chain, null if no match or null input

Since:

3.10

throwableOfType

public static <T extends Throwable> T throwableOfType(Throwable throwable,
                                                      Class<T> type,
                                                      int fromIndex)

Returns the first Throwable that matches the specified type in the exception chain from a specified index. Subclasses of the specified class do match - see throwableOfThrowable(Throwable, Class) for the opposite.

A null throwable returns null. A null type returns null. No match in the chain returns null. A negative start index is treated as zero. A start index greater than the number of throwables returns null.

Type Parameters:

T - the type of Throwable you are searching.

Parameters:

throwable - the throwable to inspect, may be null

type - the type to search for, subclasses match, null returns null

fromIndex - the (zero-based) index of the starting position, negative treated as zero, larger than chain size returns null

Returns:

the first matching throwable from the throwable chain, null if no match or null input

Since:

3.10

throwUnchecked

@Deprecated
public static <T> T throwUnchecked(T throwable)

Deprecated. Use throwUnchecked(Throwable).

Tests whether the specified Throwable is unchecked and throws it if so.

Type Parameters:

T - The Throwable type.

Parameters:

throwable - the throwable to test and throw or return.

Returns:

the given throwable.

Since:

3.13.0

throwUnchecked

public static <T extends Throwable> T throwUnchecked(T throwable)

Tests whether the specified Throwable is unchecked and throws it if so.

Type Parameters:

T - The Throwable type.

Parameters:

throwable - the throwable to test and throw or return.

Returns:

the given throwable.

Since:

3.14.0

wrapAndThrow

public static <R> R wrapAndThrow(Throwable throwable)

Throws a checked exception without adding the exception to the throws clause of the calling method. For checked exceptions, this method throws an UndeclaredThrowableException wrapping the checked exception. For Errors and RuntimeExceptions, the original exception is rethrown.

The downside to using this approach is that invoking code which needs to handle specific checked exceptions must sniff up the exception chain to determine if the caught exception was caused by the checked exception.

Type Parameters:

R - The type of the returned value.

Parameters:

throwable - The throwable to rethrow.

Returns:

Never actually returned, this generic type matches any type which the calling site requires. "Returning" the results of this method will satisfy the Java compiler requirement that all code paths return a value.

Since:

3.5

See Also:

asRuntimeException(Throwable), hasCause(Throwable, Class)