Checking in SkinKey class for per-request skin caching.

src/helma/scripting/rhino/SkinKey.java

@@ -0,0 +1,73 @@
+/*
+ * Helma License Notice
+ *
+ * The contents of this file are subject to the Helma License
+ * Version 2.0 (the "License"). You may not use this file except in
+ * compliance with the License. A copy of the License is available at
+ * http://adele.helma.org/download/helma/license.txt
+ *
+ * Copyright 1998-2003 Helma Software. All Rights Reserved.
+ *
+ * $RCSfile$
+ * $Author$
+ * $Revision$
+ * $Date$
+ */
+
+package helma.scripting.rhino;
+
+import java.io.Serializable;
+
+/**
+ *  A helper class to serve as Map key for two strings
+ */
+final class SkinKey {
+
+    private final String type;
+
+    private final String id;
+
+    // lazily initialized hashcode
+    private transient int hashcode = 0;
+
+    /**
+     * make a key for a persistent Object, describing its datasource and id.
+     */
+    public SkinKey(String type, String id) {
+        this.type = type == null ? "" : type;
+        this.id = id;
+    }
+
+    /**
+     *
+     *
+     * @param what the other key to be compared with this one
+     *
+     * @return true if both keys are identical
+     */
+    public boolean equals(Object what) {
+
+        if (!(what instanceof SkinKey)) {
+            return false;
+        }
+
+        SkinKey k = (SkinKey) what;
+
+        return (type.equals(k.type)) && (id.equals(k.id));
+    }
+
+    /**
+     *
+     *
+     * @return this key's hash code
+     */
+    public int hashCode() {
+        if (hashcode == 0) {
+            hashcode = (17 + (37 * type.hashCode()) +
+                        (+37 * id.hashCode()));
+        }
+
+        return hashcode;
+    }
+
+}