# HG changeset patch
# User mduigou
# Date 1319059067 25200
# Node ID 331fdf9a88249043f10a82ea99285f273f6ee48b
# Parent 34cd7a6c34683e20ffde7d417940d2c821d4d7c9
5029031: Add Collections.checkedQueue()
Reviewed-by: mduigou
Contributed-by: darryl.mocek@oracle.com
diff -r 34cd7a6c3468 -r 331fdf9a8824 jdk/src/share/classes/java/util/Collections.java
--- a/jdk/src/share/classes/java/util/Collections.java Wed Oct 19 10:16:22 2011 -0400
+++ b/jdk/src/share/classes/java/util/Collections.java Wed Oct 19 14:17:47 2011 -0700
@@ -2352,6 +2352,64 @@
}
/**
+ * Returns a dynamically typesafe view of the specified queue.
+ * Any attempt to insert an element of the wrong type will result in
+ * an immediate {@link ClassCastException}. Assuming a queue contains
+ * no incorrectly typed elements prior to the time a dynamically typesafe
+ * view is generated, and that all subsequent access to the queue
+ * takes place through the view, it is <i>guaranteed</i> that the
+ * queue cannot contain an incorrectly typed element.
+ *
+ * <p>A discussion of the use of dynamically typesafe views may be
+ * found in the documentation for the {@link #checkedCollection
+ * checkedCollection} method.
+ *
+ * <p>The returned queue will be serializable if the specified queue
+ * is serializable.
+ *
+ * <p>Since {@code null} is considered to be a value of any reference
+ * type, the returned queue permits insertion of {@code null} elements
+ * whenever the backing queue does.
+ *
+ * @param queue the queue for which a dynamically typesafe view is to be
+ * returned
+ * @param type the type of element that {@code queue} is permitted to hold
+ * @return a dynamically typesafe view of the specified queue
+ * @since 1.8
+ */
+ public static <E> Queue<E> checkedQueue(Queue<E> queue, Class<E> type) {
+ return new CheckedQueue<>(queue, type);
+ }
+
+ /**
+ * @serial include
+ */
+ static class CheckedQueue<E>
+ extends CheckedCollection<E>
+ implements Queue<E>, Serializable
+ {
+ private static final long serialVersionUID = 1433151992604707767L;
+ final Queue<E> queue;
+
+ CheckedQueue(Queue<E> queue, Class<E> elementType) {
+ super(queue, elementType);
+ this.queue = queue;
+ }
+
+ public E element() {return queue.element();}
+ public boolean equals(Object o) {return o == this || c.equals(o);}
+ public int hashCode() {return c.hashCode();}
+ public E peek() {return queue.peek();}
+ public E poll() {return queue.poll();}
+ public E remove() {return queue.remove();}
+
+ public boolean offer(E e) {
+ typeCheck(e);
+ return add(e);
+ }
+ }
+
+ /**
* Returns a dynamically typesafe view of the specified set.
* Any attempt to insert an element of the wrong type will result in
* an immediate {@link ClassCastException}. Assuming a set contains
diff -r 34cd7a6c3468 -r 331fdf9a8824 jdk/test/java/util/Collections/CheckedQueue.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/util/Collections/CheckedQueue.java Wed Oct 19 14:17:47 2011 -0700
@@ -0,0 +1,190 @@
+/*
+ * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 5020931
+ * @summary Unit test for Collections.checkedQueue
+ */
+
+import java.lang.reflect.Method;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.Queue;
+import java.util.concurrent.ArrayBlockingQueue;
+
+public class CheckedQueue {
+ static int status = 0;
+
+ public static void main(String[] args) throws Exception {
+ new CheckedQueue();
+ }
+
+ public CheckedQueue() throws Exception {
+ run();
+ }
+
+ private void run() throws Exception {
+ Method[] methods = this.getClass().getDeclaredMethods();
+
+ for (int i = 0; i < methods.length; i++) {
+ Method method = methods[i];
+ String methodName = method.getName();
+
+ if (methodName.startsWith("test")) {
+ try {
+ Object obj = method.invoke(this, new Object[0]);
+ } catch(Exception e) {
+ throw new Exception(this.getClass().getName() + "." +
+ methodName + " test failed, test exception "
+ + "follows\n" + e.getCause());
+ }
+ }
+ }
+ }
+
+ /**
+ * This test adds items to a queue.
+ */
+ private void test00() {
+ int arrayLength = 10;
+ ArrayBlockingQueue<String> abq = new ArrayBlockingQueue(arrayLength);
+
+ for (int i = 0; i < arrayLength; i++) {
+ abq.add(new String(Integer.toString(i)));
+ }
+ }
+
+ /**
+ * This test tests the CheckedQueue.add method. It creates a queue of
+ * {@code String}s gets the checked queue, and attempt to add an Integer to
+ * the checked queue.
+ */
+ private void test01() throws Exception {
+ int arrayLength = 10;
+ ArrayBlockingQueue<String> abq = new ArrayBlockingQueue(arrayLength + 1);
+
+ for (int i = 0; i < arrayLength; i++) {
+ abq.add(new String(Integer.toString(i)));
+ }
+
+ Queue q = Collections.checkedQueue(abq, String.class);
+
+ try {
+ q.add(new Integer(0));
+ throw new Exception(this.getClass().getName() + "." + "test01 test"
+ + " failed, should throw ClassCastException.");
+ } catch(ClassCastException cce) {
+ // Do nothing.
+ }
+ }
+
+ /**
+ * This test tests the CheckedQueue.add method. It creates a queue of one
+ * {@code String}, gets the checked queue, and attempt to add an Integer to
+ * the checked queue.
+ */
+ private void test02() throws Exception {
+ ArrayBlockingQueue<String> abq = new ArrayBlockingQueue(1);
+ Queue q = Collections.checkedQueue(abq, String.class);
+
+ try {
+ q.add(new Integer(0));
+ throw new Exception(this.getClass().getName() + "." + "test02 test"
+ + " failed, should throw ClassCastException.");
+ } catch(ClassCastException e) {
+ // Do nothing.
+ }
+ }
+
+ /**
+ * This test tests the Collections.checkedQueue method call for nulls in
+ * each and both of the parameters.
+ */
+ private void test03() throws Exception {
+ ArrayBlockingQueue<String> abq = new ArrayBlockingQueue(1);
+ Queue q;
+
+ try {
+ q = Collections.checkedQueue(null, String.class);
+ throw new Exception(this.getClass().getName() + "." + "test03 test"
+ + " failed, should throw NullPointerException.");
+ } catch(NullPointerException npe) {
+ // Do nothing
+ }
+
+ try {
+ q = Collections.checkedQueue(abq, null);
+ throw new Exception(this.getClass().getName() + "." + "test03 test"
+ + " failed, should throw NullPointerException.");
+ } catch(Exception e) {
+ // Do nothing
+ }
+
+ try {
+ q = Collections.checkedQueue(null, null);
+ throw new Exception(this.getClass().getName() + "." + "test03 test"
+ + " failed, should throw NullPointerException.");
+ } catch(Exception e) {
+ // Do nothing
+ }
+ }
+
+ /**
+ * This test tests the CheckedQueue.offer method.
+ */
+ private void test04() throws Exception {
+ ArrayBlockingQueue<String> abq = new ArrayBlockingQueue(1);
+ Queue q = Collections.checkedQueue(abq, String.class);
+
+ try {
+ q.offer(null);
+ throw new Exception(this.getClass().getName() + "." + "test04 test"
+ + " failed, should throw NullPointerException.");
+ } catch (NullPointerException npe) {
+ // Do nothing
+ }
+
+ try {
+ q.offer(new Integer(0));
+ throw new Exception(this.getClass().getName() + "." + "test04 test"
+ + " failed, should throw ClassCastException.");
+ } catch (ClassCastException cce) {
+ // Do nothing
+ }
+
+ q.offer(new String("0"));
+
+ try {
+ q.offer(new String("1"));
+ throw new Exception(this.getClass().getName() + "." + "test04 test"
+ + " failed, should throw IllegalStateException.");
+ } catch(IllegalStateException ise) {
+ // Do nothing
+ }
+ }
+
+ private void test05() {
+
+ }
+}