juneau-core/juneau-marshall/src/main/java/org/apache/juneau/internal/ThrowableUtils.java

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// *  http://www.apache.org/licenses/LICENSE-2.0                                                                             *
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// ***************************************************************************************************************************
package org.apache.juneau.internal;

/**
 * Various utility methods for creating and working with throwables.
 */
public class ThrowableUtils {

	/**
	 * Same as {@link Throwable#getCause()} but searches the throwable chain for an exception of the specified type.
	 *
	 * @param c The throwable type to search for.
	 * @param <T> The throwable type to search for.
	 * @param t The throwable to search.
	 * @return The exception, or <jk>null</jk> if not found.
	 */
	@SuppressWarnings("unchecked")
	public static <T extends Throwable> T getCause(Class<T> c, Throwable t) {
		while (t != null) {
			t = t.getCause();
			if (c.isInstance(t))
				return (T)t;
		}
		return null;
	}
}