From 35041694f498c8e4b9620f33d1eeb04c2cbe528a Mon Sep 17 00:00:00 2001
From: Stephen Colebourne <scolebourne@apache.org>
Date: Sun, 8 Dec 2002 15:29:59 +0000
Subject: [PATCH] Add new countMatches method

git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/collections/trunk@130883 13f79535-47bb-0310-9956-ffa450edef68
---
 .../commons/collections/CollectionUtils.java  | 27 ++++++++++++++++---
 1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/src/java/org/apache/commons/collections/CollectionUtils.java b/src/java/org/apache/commons/collections/CollectionUtils.java
index 8dbbb61ee..1cfbe6806 100644
--- a/src/java/org/apache/commons/collections/CollectionUtils.java
+++ b/src/java/org/apache/commons/collections/CollectionUtils.java
@@ -1,7 +1,7 @@
 /*
- * $Id: CollectionUtils.java,v 1.21 2002/11/24 21:11:27 scolebourne Exp $
- * $Revision: 1.21 $
- * $Date: 2002/11/24 21:11:27 $
+ * $Id: CollectionUtils.java,v 1.22 2002/12/08 15:29:59 scolebourne Exp $
+ * $Revision: 1.22 $
+ * $Date: 2002/12/08 15:29:59 $
  *
  * ====================================================================
  *
@@ -84,7 +84,7 @@ import org.apache.commons.collections.iterators.EnumerationIterator;
  * @author Steve Downey
  * @author <a href="herve.quiroz@esil.univ-mrs.fr">Herve Quiroz</a>
  * @author BluePhelix@web.de (Peter)
- * @version $Revision: 1.21 $ $Date: 2002/11/24 21:11:27 $
+ * @version $Revision: 1.22 $ $Date: 2002/12/08 15:29:59 $
  */
 public class CollectionUtils {
 
@@ -425,9 +425,25 @@ public class CollectionUtils {
         }
     }
 
+    /** 
+     * Counts the number of elements in the input collection that match the predicate.
+     * <p>
+     * A <code>null</code> predicate matches no elements.
+     * 
+     * @param inputCollection  the collection to get the input from, may not be null
+     * @param predicate  the predicate to use, may be null
+     * @return the number of matches for the predicate in the collection
+     * @throws NullPointerException if the input collection is null
+     */
+    public static int countMatches(Collection inputCollection, Predicate predicate) {
+        return select(inputCollection, predicate).size();
+    }
+
     /** 
      * Selects all elements from input collection which match the given predicate
      * into an output collection.
+     * <p>
+     * A <code>null</code> predicate matches no elements.
      * 
      * @param inputCollection  the collection to get the input from, may not be null
      * @param predicate  the predicate to use, may be null
@@ -467,6 +483,8 @@ public class CollectionUtils {
     /**
      * Selects all elements from inputCollection which don't match the given predicate
      * into an output collection
+     * <p>
+     * A <code>null</code> predicate matches no elements.
      * 
      * @param inputCollection  the collection to get the input from, may not be null
      * @param predicate  the predicate to use, may be null
@@ -499,6 +517,7 @@ public class CollectionUtils {
             }
         }
     }
+    
     /** 
      * Transforms all elements from inputCollection with the given transformer 
      * and adds them to the outputCollection.