ExceptionUtilTest.java
/**
* The contents of this file are subject to the OpenMRS Public License
* Version 1.0 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://license.openmrs.org
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
* License for the specific language governing rights and limitations
* under the License.
*
* Copyright (C) OpenMRS, LLC. All Rights Reserved.
*/
package org.openmrs.util;
import java.lang.reflect.Constructor;
import java.util.Arrays;
import java.util.List;
import org.junit.Assert;
import org.junit.Test;
public class ExceptionUtilTest {
/**
* @see ExceptionUtil#rethrowIfCause(Throwable,Class)
* @verifies allow an intermediate exception to be rethrown
*/
@Test
public void rethrowIfCause_shouldAllowAnIntermediateExceptionToBeRethrown() throws Exception {
try {
@SuppressWarnings("unchecked")
List<Class<? extends RuntimeException>> chain = Arrays.asList(NullPointerException.class,
IllegalArgumentException.class, IllegalStateException.class);
throwExceptionChain(chain);
}
catch (Exception ex) {
int numFound = 0;
// Should be able to find the innermost NPE
Exception innermost = null;
try {
ExceptionUtil.rethrowIfCause(ex, NullPointerException.class);
}
catch (Exception cause) {
Assert.assertNull(cause.getCause());
innermost = cause;
++numFound;
}
// Should be able to find the middle IllegalArgumentException
try {
ExceptionUtil.rethrowIfCause(ex, IllegalArgumentException.class);
}
catch (Exception middle) {
Assert.assertEquals(innermost, middle.getCause());
++numFound;
}
// Should be able to find the outermost IllegalStateException
try {
ExceptionUtil.rethrowIfCause(ex, IllegalStateException.class);
}
catch (Exception outer) {
Assert.assertEquals(ex, outer);
++numFound;
}
Assert.assertEquals(3, numFound);
}
}
/**
* Recursively builds up an exception chain with the requested exception classes in it.
*
* @param classesInChain the start of the list is the root cause, and the end of the list is the outermost wrapped exception
*/
private void throwExceptionChain(List<Class<? extends RuntimeException>> classesInChain) throws Exception {
if (classesInChain.size() > 1) {
try {
throwExceptionChain(classesInChain.subList(0, classesInChain.size() - 1));
}
catch (Exception ex) {
Class<? extends Exception> outer = classesInChain.get(classesInChain.size() - 1);
Constructor<? extends Exception> constructor = outer.getConstructor(Throwable.class);
throw constructor.newInstance(ex);
}
} else {
// length should be 1
Class<? extends Exception> classToThrow = classesInChain.get(0);
throw classToThrow.newInstance();
}
}
}