Package com.google.api.client.util

Class Throwables

java.lang.Object

com.google.api.client.util.Throwables

public final class Throwables
extends Object

Static utility methods pertaining to instances of Throwable.

NOTE: proxy for the Guava implementation of Throwables.

Since:

1.14

Author:

Yaniv Inbar

Method Summary

Modifier and Type	Method	Description
static RuntimeException	propagate(Throwable throwable)	Propagates throwable as-is if it is an instance of RuntimeException or Error, or else as a last resort, wraps it in a RuntimeException then propagates.
static void	propagateIfPossible(Throwable throwable)	Propagates throwable exactly as-is, if and only if it is an instance of RuntimeException or Error.
static <X extends Throwable> void	propagateIfPossible(Throwable throwable, Class<X> declaredType)	Propagates throwable exactly as-is, if and only if it is an instance of RuntimeException, Error, or declaredType.

Methods inherited from class java.lang.Object

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

Method Detail

propagate

public static RuntimeException propagate(Throwable throwable)

Propagates throwable as-is if it is an instance of RuntimeException or Error, or else as a last resort, wraps it in a RuntimeException then propagates.

This method always throws an exception. The RuntimeException return type is only for client code to make Java type system happy in case a return value is required by the enclosing method. Example usage:

    T doSomething() {
      try {
        return someMethodThatCouldThrowAnything();
      } catch (IKnowWhatToDoWithThisException e) {
        return handle(e);
      } catch (Throwable t) {
        throw Throwables.propagate(t);
      }
    }

Parameters:

throwable - the Throwable to propagate

Returns:

nothing will ever be returned; this return type is only for your convenience, as illustrated in the example above

propagateIfPossible

public static void propagateIfPossible(Throwable throwable)

Propagates throwable exactly as-is, if and only if it is an instance of RuntimeException or Error. Example usage:

    try {
      someMethodThatCouldThrowAnything();
    } catch (IKnowWhatToDoWithThisException e) {
      handle(e);
    } catch (Throwable t) {
      Throwables.propagateIfPossible(t);
      throw new RuntimeException("unexpected", t);
    }
 

Parameters:

throwable - throwable (may be null)

propagateIfPossible

public static <X extends Throwable> void propagateIfPossible(Throwable throwable,
                                                             Class<X> declaredType)
                                                      throws X extends Throwable

Propagates throwable exactly as-is, if and only if it is an instance of RuntimeException, Error, or declaredType. Example usage:

    try {
      someMethodThatCouldThrowAnything();
    } catch (IKnowWhatToDoWithThisException e) {
      handle(e);
    } catch (Throwable t) {
      Throwables.propagateIfPossible(t, OtherException.class);
      throw new RuntimeException("unexpected", t);
    }

Parameters:

throwable - throwable (may be null)

declaredType - the single checked exception type declared by the calling method

Throws:

X extends Throwable