From 5cbde1b45635b63f8302476e0ceadada01f6123a Mon Sep 17 00:00:00 2001
From: "ray.j.greenwell" <ray.j.greenwell@6335cc39-0255-0410-8fd6-9bcaacd3b74c>
Date: Tue, 21 Sep 2010 02:11:03 +0000
Subject: [PATCH] Created an addAll() that folds a supplied Iterable of
 Collections into the starter collection using addAll. Certain Collections,
 like guava's Multiset have optimized addAll() methods that recognize other
 Multisets. There is also a putAll() equivalent for Maps.

git-svn-id: https://samskivert.googlecode.com/svn/trunk@2891 6335cc39-0255-0410-8fd6-9bcaacd3b74c
---
 .../com/samskivert/util/CollectionUtil.java   | 25 +++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/src/main/java/com/samskivert/util/CollectionUtil.java b/src/main/java/com/samskivert/util/CollectionUtil.java
index ceae52f1..20b9f3a0 100644
--- a/src/main/java/com/samskivert/util/CollectionUtil.java
+++ b/src/main/java/com/samskivert/util/CollectionUtil.java
@@ -28,6 +28,7 @@ import java.util.Comparator;
 import java.util.Enumeration;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Map;
 import java.util.NoSuchElementException;
 
 import com.samskivert.annotation.ReplacedBy;
@@ -79,6 +80,30 @@ public class CollectionUtil
         return col;
     }
 
+    /**
+     * Folds all the specified values into the supplied collection and returns it.
+     */
+    public static <T, C extends Collection<T>> C addAll (
+        C col, Iterable<? extends Collection<? extends T>> values)
+    {
+        for (Collection<? extends T> val : values) {
+            col.addAll(val);
+        }
+        return col;
+    }
+
+    /**
+     * Folds all the specified values into the supplied map and returns it.
+     */
+    public static <K, V, M extends Map<K, V>> M putAll (
+        M map, Iterable<? extends Map<? extends K, ? extends V>> values)
+    {
+        for (Map<? extends K, ? extends V> val : values) {
+            map.putAll(val);
+        }
+        return map;
+    }
+
     /**
      * Modify the specified Collection so that only the first <code>limit</code> elements
      * remain, as determined by iteration order. If the Collection is smaller than limit,