Author: brentworden
Date: Tue May 24 18:28:13 2011
New Revision: 1127199
URL: http://svn.apache.org/viewvc?rev=1127199&view=rev
Log:
COLLECTIONS-313. Added abstract closure that is capable of handling thrown
exceptions from closure execution.
Added:
commons/proper/collections/trunk/src/java/org/apache/commons/collections/functors/CatchAndRethrowClosure.java
commons/proper/collections/trunk/src/test/org/apache/commons/collections/functors/BasicClosureTestBase.java
commons/proper/collections/trunk/src/test/org/apache/commons/collections/functors/TestCatchAndRethrowClosure.java
Added:
commons/proper/collections/trunk/src/java/org/apache/commons/collections/functors/CatchAndRethrowClosure.java
URL:
http://svn.apache.org/viewvc/commons/proper/collections/trunk/src/java/org/apache/commons/collections/functors/CatchAndRethrowClosure.java?rev=1127199&view=auto
==============================================================================
---
commons/proper/collections/trunk/src/java/org/apache/commons/collections/functors/CatchAndRethrowClosure.java
(added)
+++
commons/proper/collections/trunk/src/java/org/apache/commons/collections/functors/CatchAndRethrowClosure.java
Tue May 24 18:28:13 2011
@@ -0,0 +1,76 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.collections.functors;
+
+import org.apache.commons.collections.Closure;
+import org.apache.commons.collections.FunctorException;
+
+/**
+ * {@link Closure} that catches any checked exception and re-throws it as a
+ * {@link FunctorException} runtime exception. Example usage:
+ *
+ * <pre>
+ * // Create a catch and re-throw closure via anonymous subclass
+ * CatchAndRethrowClosure<String> writer = new ThrowingClosure() {
+ * private java.io.Writer out = // some writer
+ *
+ * protected void executeAndThrow(String input) throws IOException {
+ * out.write(input); // throwing of IOException allowed
+ * }
+ * };
+ *
+ * // use catch and re-throw closure
+ * java.util.List<String> strList = // some list
+ * try {
+ * CollctionUtils.forAllDo(strList, writer);
+ * } catch (FunctorException ex) {
+ * Throwable originalError = ex.getCause();
+ * // handle error
+ * }
+ * </pre>
+ *
+ * @since Commons Collections 4.0
+ * @version $Revision: $ $Date: $
+ */
+public abstract class CatchAndRethrowClosure<E> implements Closure<E> {
+
+ /**
+ * Execute this closure on the specified input object.
+ *
+ * @param input the input to execute on
+ * @throws ClosureException (runtime) if the closure execution resulted in
a
+ * checked exception.
+ */
+ public void execute(E input) {
+ try {
+ executeAndThrow(input);
+ } catch (RuntimeException ex) {
+ throw ex;
+ } catch (Throwable t) {
+ throw new FunctorException(t);
+ }
+ }
+
+ /**
+ * Execute this closure on the specified input object.
+ *
+ * @param input the input to execute on
+ * @throws Throwable if the closure execution resulted in a checked
+ * exception.
+ */
+ protected abstract void executeAndThrow(E input) throws Throwable;
+}
Added:
commons/proper/collections/trunk/src/test/org/apache/commons/collections/functors/BasicClosureTestBase.java
URL:
http://svn.apache.org/viewvc/commons/proper/collections/trunk/src/test/org/apache/commons/collections/functors/BasicClosureTestBase.java?rev=1127199&view=auto
==============================================================================
---
commons/proper/collections/trunk/src/test/org/apache/commons/collections/functors/BasicClosureTestBase.java
(added)
+++
commons/proper/collections/trunk/src/test/org/apache/commons/collections/functors/BasicClosureTestBase.java
Tue May 24 18:28:13 2011
@@ -0,0 +1,35 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.collections.functors;
+
+import org.apache.commons.collections.Closure;
+import org.junit.Assert;
+import org.junit.Test;
+
+public abstract class BasicClosureTestBase {
+
+ @Test
+ public void closureSanityTests() throws Exception {
+ Closure<?> closure = generateClosure();
+ Assert.assertNotNull(closure);
+ }
+
+ /**
+ * @return a closure for general sanity tests.
+ */
+ protected abstract <T> Closure<T> generateClosure();
+}
Added:
commons/proper/collections/trunk/src/test/org/apache/commons/collections/functors/TestCatchAndRethrowClosure.java
URL:
http://svn.apache.org/viewvc/commons/proper/collections/trunk/src/test/org/apache/commons/collections/functors/TestCatchAndRethrowClosure.java?rev=1127199&view=auto
==============================================================================
---
commons/proper/collections/trunk/src/test/org/apache/commons/collections/functors/TestCatchAndRethrowClosure.java
(added)
+++
commons/proper/collections/trunk/src/test/org/apache/commons/collections/functors/TestCatchAndRethrowClosure.java
Tue May 24 18:28:13 2011
@@ -0,0 +1,93 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.collections.functors;
+
+import java.io.IOException;
+
+import org.apache.commons.collections.Closure;
+import org.apache.commons.collections.FunctorException;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestCatchAndRethrowClosure extends BasicClosureTestBase {
+
+ private static <T> Closure<T> generateIOExceptionClosure() {
+ return new CatchAndRethrowClosure<T>() {
+
+ @Override
+ protected void executeAndThrow(T input) throws IOException {
+ throw new IOException();
+ }
+ };
+ }
+
+ private static <T> Closure<T> generateNullPointerExceptionClosure() {
+ return new CatchAndRethrowClosure<T>() {
+
+ @Override
+ protected void executeAndThrow(T input) {
+ throw new NullPointerException();
+ }
+ };
+ }
+
+ private static <T> Closure<T> generateNoExceptionClosure() {
+ return new CatchAndRethrowClosure<T>() {
+
+ @Override
+ protected void executeAndThrow(T input) {
+ }
+ };
+ }
+
+ @Override
+ protected <T> Closure<T> generateClosure() {
+ return generateNoExceptionClosure();
+ }
+
+ @Test
+ public void testThrowingClosure() {
+ Closure<Integer> closure = generateNoExceptionClosure();
+ try {
+ closure.execute(Integer.valueOf(0));
+ } catch (FunctorException ex) {
+ Assert.fail();
+ } catch (RuntimeException ex) {
+ Assert.fail();
+ }
+
+ closure = generateIOExceptionClosure();
+ try {
+ closure.execute(Integer.valueOf(0));
+ Assert.fail();
+ } catch (FunctorException ex) {
+ Assert.assertTrue(ex.getCause() instanceof IOException);
+ } catch (RuntimeException ex) {
+ Assert.fail();
+ }
+
+ closure = generateNullPointerExceptionClosure();
+ try {
+ closure.execute(Integer.valueOf(0));
+ Assert.fail();
+ } catch (FunctorException ex) {
+ Assert.fail();
+ } catch (RuntimeException ex) {
+ Assert.assertTrue(ex instanceof NullPointerException);
+ }
+ }
+}
