some enhancements to ERXMultiKey

• use constant empty array for empty multi key
• keys() returns copy of keys
• keysNoCopy() for those who know what they do ;)
• equals tests first for object equality

Frameworks/Core/ERExtensions/Sources/er/extensions/foundation/ERXMultiKey.java

@@ -10,6 +10,7 @@
 
 import com.webobjects.eoaccess.EOEntity;
 import com.webobjects.foundation.NSArray;
+import com.webobjects.foundation._NSCollectionPrimitives;
 
 /**
  * Simple class to use multiple objects as
@@ -40,7 +41,7 @@ private ERXMultiKey(short keyCount) {
      */
     public ERXMultiKey() {
         _keyCount=0;
-        _keys=new Object[0];
+        _keys=_NSCollectionPrimitives.EmptyArray;
         recomputeHashCode();
     }
 
@@ -51,7 +52,7 @@ public ERXMultiKey() {
      */
     public ERXMultiKey(Object[] keys) {
         this((short)keys.length);
-        System.arraycopy(keys,0,_keys,0,(int)_keyCount);
+        System.arraycopy(keys,0,_keys,0,_keyCount);
         recomputeHashCode();
     }
 
@@ -60,8 +61,8 @@ public ERXMultiKey(Object[] keys) {
      * array.
      * @param keys array of keys
      */    
-    public ERXMultiKey(NSArray keys) {
-        this ((short)keys.count());
+    public ERXMultiKey(NSArray<Object> keys) {
+        this((short)keys.count());
         for (int i=0; i<keys.count(); i++) _keys[i]=keys.objectAtIndex(i);
         recomputeHashCode();
    }
@@ -71,7 +72,7 @@ public ERXMultiKey(NSArray keys) {
      * vector.
      * @param keys vector of keys
      */
-    public ERXMultiKey(Vector keys) {
+    public ERXMultiKey(Vector<Object> keys) {
         this ((short)keys.size());
         for (int i=0; i<keys.size(); i++) _keys[i]=keys.elementAt(i);
         recomputeHashCode();
@@ -86,25 +87,43 @@ public ERXMultiKey(Vector keys) {
     public ERXMultiKey(Object key, Object ... keys) {
         this((short)(keys.length + 1));
         _keys[0] = key;
-        System.arraycopy(keys,0,_keys,1,(int)_keyCount-1);
+        System.arraycopy(keys,0,_keys,1,_keyCount-1);
         recomputeHashCode();
     }
 
+    /**
+     * Method used to return a copy of the object array
+     * of keys for the current multi-key.
+     * @return object array of keys
+     */    
+    public final Object[] keys() {
+    	Object[] keys;
+    	if (_keyCount == 0) {
+    		keys = _keys;
+    	} else {
+    		keys = new Object[_keyCount];
+    		System.arraycopy(_keys, 0, keys, 0, _keyCount);
+    	}
+    	return keys;
+    }
+
     /**
      * Method used to return the object array
      * of keys for the current multi-key.<br />
      * DO NOT MODIFY!
      * @return object array of keys
-     */    
-    // FIXME: should return a copy
-    public final Object[] keys() { return _keys; }
+     */  
+    public final Object[] keysNoCopy() {
+		return _keys;
+	}
 
     /**
      * Calculates a unique hash code for
      * the given array of keys.
      * @return unique hash code for the array
      *		of keys.
      */
+    @Override
     public final int hashCode() {
         return _hashCode;
     }
@@ -136,9 +155,12 @@ public final void recomputeHashCode() {
      * @param o object to be compared
      * @return result of comparison
      */
+    @Override
     public final boolean equals(Object o) {
     	if (o instanceof ERXMultiKey) {
     		ERXMultiKey o2 = (ERXMultiKey) o;
+    		if (this == o2)
+    			return true;
     		if (_keyCount!=o2._keyCount)
     			return false;
     		if (hashCode()!=o2.hashCode())
@@ -158,15 +180,16 @@ public final boolean equals(Object o) {
      * String representation of the multi-key.
      * @return string representation of key.
      */
+    @Override
     public String toString() {
-        StringBuffer result=new StringBuffer("(");
+        StringBuilder result = new StringBuilder('(');
         for (short i=0; i<_keys.length; i++) {
             Object o=_keys[i];
             result.append(o instanceof EOEntity ? ((EOEntity)o).name() : o != null ? o.toString() : "<NULL>");
             if(i != _keys.length-1)
                 result.append(", ");
         }
-        result.append(")");
+        result.append(')');
         return result.toString();
     }
 }