1 files changed, 60 insertions, 0 deletions
diff --git a/watchmaker/framework/src/java/main/org/uncommons/util/id/StringPrefixIDSource.java b/watchmaker/framework/src/java/main/org/uncommons/util/id/StringPrefixIDSource.java
new file mode 100644
index 0000000..c4d683c
--- /dev/null
+++ b/watchmaker/framework/src/java/main/org/uncommons/util/id/StringPrefixIDSource.java
@@ -0,0 +1,60 @@
+//=============================================================================
+// Copyright 2006-2010 Daniel W. Dyer
+//
+// Licensed 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.uncommons.util.id;
+
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+/**
+ * Thread-safe ID source that wraps another source of IDs and adds a fixed String
+ * prefix to each ID generated.
+ * @author Daniel Dyer
+ */
+public class StringPrefixIDSource implements IDSource<String>
+{
+    private final Lock lock = new ReentrantLock();
+    private final String prefix;
+    private final IDSource<?> source;
+
+    /**
+     * @param prefix A fixed String that is attached to the front of each ID.
+     * @param source The source of IDs to which the prefix is added.
+     */
+    public StringPrefixIDSource(String prefix, IDSource<?> source)
+    {
+        this.prefix = prefix;
+        this.source = source;
+    }
+
+
+    /**
+     * {@inheritDoc}
+     */
+    public String nextID()
+    {
+        lock.lock();
+        try
+        {
+            StringBuilder output = new StringBuilder(prefix);
+            output.append(source.nextID());
+            return output.toString();
+        }
+        finally
+        {
+            lock.unlock();
+        }
+    }
+}