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Posted to commits@commons.apache.org by tn...@apache.org on 2013/03/05 22:29:51 UTC
svn commit: r1453012 - in /commons/proper/collections/trunk/src:
changes/changes.xml
main/java/org/apache/commons/collections/CollectionUtils.java
test/java/org/apache/commons/collections/CollectionUtilsTest.java
Author: tn
Date: Tue Mar 5 21:29:50 2013
New Revision: 1453012
URL: http://svn.apache.org/r1453012
Log:
[COLLECTIONS-446] Added method isEqualCollection(Collection, Collection, Equator) to CollectionUtils.
Modified:
commons/proper/collections/trunk/src/changes/changes.xml
commons/proper/collections/trunk/src/main/java/org/apache/commons/collections/CollectionUtils.java
commons/proper/collections/trunk/src/test/java/org/apache/commons/collections/CollectionUtilsTest.java
Modified: commons/proper/collections/trunk/src/changes/changes.xml
URL: http://svn.apache.org/viewvc/commons/proper/collections/trunk/src/changes/changes.xml?rev=1453012&r1=1453011&r2=1453012&view=diff
==============================================================================
--- commons/proper/collections/trunk/src/changes/changes.xml (original)
+++ commons/proper/collections/trunk/src/changes/changes.xml Tue Mar 5 21:29:50 2013
@@ -22,6 +22,9 @@
<body>
<release version="4.0" date="TBA" description="Next release">
+ <action issue="COLLECTIONS-446" dev="tn" type="add" due-to="Matt Lachman">
+ Added method "CollectionUtils#isEqualCollection(Collection, Collection, Equator)".
+ </action>
<action issue="COLLECTIONS-447" dev="tn" type="fix" due-to="Jeffrey Barnes">
Tree traversal with a TreeListIterator will not be affected anymore by
the removal of an element directly after a call to previous().
Modified: commons/proper/collections/trunk/src/main/java/org/apache/commons/collections/CollectionUtils.java
URL: http://svn.apache.org/viewvc/commons/proper/collections/trunk/src/main/java/org/apache/commons/collections/CollectionUtils.java?rev=1453012&r1=1453011&r2=1453012&view=diff
==============================================================================
--- commons/proper/collections/trunk/src/main/java/org/apache/commons/collections/CollectionUtils.java (original)
+++ commons/proper/collections/trunk/src/main/java/org/apache/commons/collections/CollectionUtils.java Tue Mar 5 21:29:50 2013
@@ -34,6 +34,7 @@ import org.apache.commons.collections.co
import org.apache.commons.collections.collection.TransformedCollection;
import org.apache.commons.collections.collection.UnmodifiableBoundedCollection;
import org.apache.commons.collections.collection.UnmodifiableCollection;
+import org.apache.commons.collections.functors.Equator;
import org.apache.commons.collections.functors.TruePredicate;
/**
@@ -523,6 +524,78 @@ public class CollectionUtils {
}
/**
+ * Returns <tt>true</tt> iff the given {@link Collection}s contain
+ * exactly the same elements with exactly the same cardinalities.
+ * <p>
+ * That is, iff the cardinality of <i>e</i> in <i>a</i> is
+ * equal to the cardinality of <i>e</i> in <i>b</i>,
+ * for each element <i>e</i> in <i>a</i> or <i>b</i>.
+ *
+ * @param a the first collection, must not be null
+ * @param b the second collection, must not be null
+ * @param equator the Equator used for testing equality
+ * @return <code>true</code> iff the collections contain the same elements with the same cardinalities.
+ * @throws IllegalArgumentException if the equator is null
+ * @since 4.0
+ */
+ @SuppressWarnings({ "unchecked", "rawtypes" }) // we don't know the types due to wildcards in the signature
+ public static boolean isEqualCollection(final Collection<?> a, final Collection<?> b, final Equator<?> equator) {
+ if (equator == null) {
+ throw new IllegalArgumentException("equator may not be null");
+ }
+
+ if(a.size() != b.size()) {
+ return false;
+ }
+
+ final Transformer transformer = new Transformer() {
+ public EquatorWrapper<?> transform(Object input) {
+ return new EquatorWrapper(equator, input);
+ }
+ };
+
+ return isEqualCollection(collect(a, transformer), collect(b, transformer));
+ }
+
+ /**
+ * Wraps another object and uses the provided Equator to implement
+ * {@link #equals(Object)} and {@link #hashCode()}.
+ * <p>
+ * This class can be used to store objects into a Map.
+ *
+ * @param <O> the element type
+ * @since 4.0
+ */
+ private static class EquatorWrapper<O> {
+ private final Equator<O> equator;
+ private final O object;
+
+ public EquatorWrapper(final Equator<O> equator, final O object) {
+ this.equator = equator;
+ this.object = object;
+ }
+
+ public O getObject() {
+ return object;
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (!(obj instanceof EquatorWrapper)) {
+ return false;
+ }
+ @SuppressWarnings("unchecked")
+ EquatorWrapper<O> otherObj = (EquatorWrapper<O>) obj;
+ return equator.equate(object, otherObj.getObject());
+ }
+
+ @Override
+ public int hashCode() {
+ return equator.hash(object);
+ }
+ }
+
+ /**
* Returns the number of occurrences of <i>obj</i> in <i>coll</i>.
*
* @param obj the object to find the cardinality of
Modified: commons/proper/collections/trunk/src/test/java/org/apache/commons/collections/CollectionUtilsTest.java
URL: http://svn.apache.org/viewvc/commons/proper/collections/trunk/src/test/java/org/apache/commons/collections/CollectionUtilsTest.java?rev=1453012&r1=1453011&r2=1453012&view=diff
==============================================================================
--- commons/proper/collections/trunk/src/test/java/org/apache/commons/collections/CollectionUtilsTest.java (original)
+++ commons/proper/collections/trunk/src/test/java/org/apache/commons/collections/CollectionUtilsTest.java Tue Mar 5 21:29:50 2013
@@ -32,6 +32,8 @@ import org.apache.commons.collections.co
import org.apache.commons.collections.collection.SynchronizedCollection;
import org.apache.commons.collections.collection.TransformedCollection;
import org.apache.commons.collections.collection.UnmodifiableCollection;
+import org.apache.commons.collections.functors.DefaultEquator;
+import org.apache.commons.collections.functors.Equator;
import org.junit.Before;
import org.junit.Test;
@@ -516,6 +518,36 @@ public class CollectionUtilsTest extends
}
@Test
+ public void testIsEqualCollectionEquator() {
+ Collection<Integer> collB = CollectionUtils.collect(collectionB, TRANSFORM_TO_INTEGER);
+
+ // odd / even equator
+ final Equator<Integer> e = new Equator<Integer>() {
+ public boolean equate(Integer o1, Integer o2) {
+ if (o1.intValue() % 2 == 0 ^ o2.intValue() % 2 == 0) return false;
+ else return true;
+ }
+
+ public int hash(Integer o) {
+ return o.intValue() % 2 == 0 ? Integer.valueOf(0).hashCode() : Integer.valueOf(1).hashCode();
+ }
+ };
+
+ assertTrue(CollectionUtils.isEqualCollection(collectionA, collectionA, e));
+ assertTrue(CollectionUtils.isEqualCollection(collectionA, collB, e));
+ assertTrue(CollectionUtils.isEqualCollection(collB, collectionA, e));
+
+ final Equator<Number> defaultEquator = new DefaultEquator<Number>();
+ assertFalse(CollectionUtils.isEqualCollection(collectionA, collectionB, defaultEquator));
+ assertFalse(CollectionUtils.isEqualCollection(collectionA, collB, defaultEquator));
+ }
+
+ @Test(expected=IllegalArgumentException.class)
+ public void testIsEqualCollectionNullEquator() {
+ CollectionUtils.isEqualCollection(collectionA, collectionA, null);
+ }
+
+ @Test
public void testIsProperSubCollection() {
final Collection<String> a = new ArrayList<String>();
final Collection<String> b = new ArrayList<String>();