Author: bayard Date: Sun Sep 11 05:47:33 2011 New Revision: 1167673 URL: http://svn.apache.org/viewvc?rev=1167673&view=rev Log: Making ComparatorChain implement Iterable. Including test and package private copy of Collections' UnmodifiableIterator
Added: commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/compare/UnmodifiableIterator.java (with props) Modified: commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/compare/ComparatorChain.java commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/compare/ComparatorChainTest.java Modified: commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/compare/ComparatorChain.java URL: http://svn.apache.org/viewvc/commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/compare/ComparatorChain.java?rev=1167673&r1=1167672&r2=1167673&view=diff ============================================================================== --- commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/compare/ComparatorChain.java (original) +++ commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/compare/ComparatorChain.java Sun Sep 11 05:47:33 2011 @@ -43,7 +43,7 @@ import java.util.List; * @since Commons Collections 2.0 * @version $Revision$ $Date$ */ -public class ComparatorChain<E> implements Comparator<E>, Serializable { +public class ComparatorChain<E> implements Comparator<E>, Serializable, Iterable { /** The list of comparators in the chain. */ protected List<Comparator<E>> comparatorChain = null; @@ -109,6 +109,16 @@ public class ComparatorChain<E> implemen //----------------------------------------------------------------------- /** + * Iterate through the chained comparators. + * + * @return Unmodifiable iterator over the chained comparators + */ + public Iterator<Comparator<E>> iterator() { + return new UnmodifiableIterator(comparatorChain.iterator()); + } + + //----------------------------------------------------------------------- + /** * Implement a hash code for this comparator that is consistent with * {@link #equals(Object) equals}. * Added: commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/compare/UnmodifiableIterator.java URL: http://svn.apache.org/viewvc/commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/compare/UnmodifiableIterator.java?rev=1167673&view=auto ============================================================================== --- commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/compare/UnmodifiableIterator.java (added) +++ commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/compare/UnmodifiableIterator.java Sun Sep 11 05:47:33 2011 @@ -0,0 +1,61 @@ +/* + * 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.lang3.compare; + +import java.util.Iterator; + +/** + * Decorates an iterator such that it cannot be modified. + * <p> + * Attempts to modify it will result in an UnsupportedOperationException. + * + * @since Commons Collections 3.0 + * @version $Revision: 1148801 $ $Date: 2011-07-20 07:44:46 -0700 (Wed, 20 Jul 2011) $ + */ +final class UnmodifiableIterator<E> implements Iterator<E> { + + /** The iterator being decorated */ + private final Iterator<E> iterator; + + //----------------------------------------------------------------------- + /** + * Constructor. + * + * @param iterator the iterator to decorate + */ + public UnmodifiableIterator(Iterator<E> iterator) { + super(); + if (iterator == null) { + throw new IllegalArgumentException("Iterator must not be null"); + } + this.iterator = iterator; + } + + //----------------------------------------------------------------------- + public boolean hasNext() { + return iterator.hasNext(); + } + + public E next() { + return iterator.next(); + } + + public void remove() { + throw new UnsupportedOperationException("remove() is not supported"); + } + +} Propchange: commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/compare/UnmodifiableIterator.java ------------------------------------------------------------------------------ svn:eol-style = native Modified: commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/compare/ComparatorChainTest.java URL: http://svn.apache.org/viewvc/commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/compare/ComparatorChainTest.java?rev=1167673&r1=1167672&r2=1167673&view=diff ============================================================================== --- commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/compare/ComparatorChainTest.java (original) +++ commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/compare/ComparatorChainTest.java Sun Sep 11 05:47:33 2011 @@ -20,6 +20,7 @@ package org.apache.commons.lang3.compare import static org.junit.Assert.*; import java.util.Comparator; +import java.util.Iterator; import org.junit.Before; import org.junit.Test; @@ -51,4 +52,20 @@ public class ComparatorChainTest { assertTrue("Comparison failed", cc.compare( "ABC-123", "ABC-123" ) == 0 ); } + @Test + public void testIterate() { + Comparator c1 = ComparableComparator.INSTANCE; + Comparator c2 = new ComparableComparator(); + Comparator c3 = new NullComparator(); + Comparator c4 = new ReverseComparator(); + Iterable cc = new ComparatorChain(c1, c2, c3, c4); + + Iterator itr = cc.iterator(); + assertEquals( "Iteration failed", c1, itr.next() ); + assertEquals( "Iteration failed", c2, itr.next() ); + assertEquals( "Iteration failed", c3, itr.next() ); + assertEquals( "Iteration failed", c4, itr.next() ); + assertFalse( "Iteration failed", itr.hasNext() ); + } + }