ExceptionUtils.java

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package org.glassfish.web.util;

import java.lang.reflect.InvocationTargetException;


/**
 * Utilities for handling Throwables and Exceptions.
 */
public class ExceptionUtils {

    /**
     * Checks whether the supplied Throwable is one that needs to be
     * rethrown and swallows all others.
     * @param t the Throwable to check
     */
    public static void handleThrowable(Throwable t) {
        if (t instanceof ThreadDeath) {
            throw (ThreadDeath) t;
        }
        if (t instanceof VirtualMachineError) {
            throw (VirtualMachineError) t;
        }
        // All other instances of Throwable will be silently swallowed
    }

    /**
     * Checks whether the supplied Throwable is an instance of
     * <code>InvocationTargetException</code> and returns the throwable that is
     * wrapped by it, if there is any.
     *
     * @param t the Throwable to check
     * @return <code>t</code> or <code>t.getCause()</code>
     */
    public static Throwable unwrapInvocationTargetException(Throwable t) {
        if (t instanceof InvocationTargetException && t.getCause() != null) {
            return t.getCause();
        }
        return t;
    }
}