- Change of heart: Let's follow the example of EnumSet, which

does not permit null (or, obviously, elements of the wrong type),
  but is gracious about simply returning false if an invalid
  Object is passed to contains() or remove().
- Implement a dumb size().
- toIntArray() impl now deals with oversize IntSets.


git-svn-id: https://samskivert.googlecode.com/svn/trunk@2657 6335cc39-0255-0410-8fd6-9bcaacd3b74c

src/java/com/samskivert/util/AbstractIntSet.java

@@ -27,8 +27,8 @@ import java.util.Iterator;
 /**
  * A base class for {@link IntSet} implementations.<p>
  *
- * All you really need to do is implement <tt>interable</tt> and <tt>size</tt>,
- * although for performance reasons you'll probably want to override <tt>contains</tt>.<p>
+ * All you really need to do is implement <tt>interable</tt>, but you'll almost certainly want
+ * to implement <tt>size</tt> and <tt>contains</tt> for enhanced performance.<p>
  *
  * To implement a modifiable IntSet, the programmer must additionally override this class's
  * <tt>add</tt> and <tt>remove</tt> methods, which will otherwise throw an
@@ -46,7 +46,7 @@ public abstract class AbstractIntSet extends AbstractSet<Integer>
     // from IntSet
     public boolean contains (int value)
     {
-        // abstract implementation. You should override.
+        // dumb implementation. You should override.
         for (Interator it = interator(); it.hasNext(); ) {
             if (it.nextInt() == value) {
                 return true;
@@ -55,6 +55,21 @@ public abstract class AbstractIntSet extends AbstractSet<Integer>
         return false;
     }
 
+    /**
+     * {@inheritDoc}
+     *
+     * <p>This implementation simply counts the elements in the interator.
+     */
+    public int size ()
+    {
+        // dumb implementation. You should override.
+        int size = 0;
+        for (Interator it = interator(); (size < Integer.MAX_VALUE) && it.hasNext(); it.nextInt()) {
+            size++;
+        }
+        return size;
+    }
+
     // from IntSet
     public boolean add (int value)
     {
@@ -77,9 +92,9 @@ public abstract class AbstractIntSet extends AbstractSet<Integer>
     public int[] toIntArray ()
     {
         int[] vals = new int[size()];
-        int ii=0;
-        for (Interator intr = interator(); intr.hasNext(); ) {
-            vals[ii++] = intr.nextInt();
+        int ii = 0;
+        for (Interator it = interator(); (ii < Integer.MAX_VALUE) && it.hasNext(); ) {
+            vals[ii++] = it.nextInt();
         }
         return vals;
     }
@@ -93,8 +108,8 @@ public abstract class AbstractIntSet extends AbstractSet<Integer>
     @Override // from AbstractSet<Integer>
     public boolean contains (Object o)
     {
-        // let's go ahead and NPE or CCE if an Integer is not specified
-        return /* (o instanceof Integer) && */ contains(((Integer)o).intValue());
+        // cope with null or non-Integer
+        return (o instanceof Integer) && contains(((Integer)o).intValue());
     }
 
     @Override // from AbstractSet<Integer>
@@ -106,8 +121,8 @@ public abstract class AbstractIntSet extends AbstractSet<Integer>
     @Override // from AbstractSet<Integer>
     public boolean remove (Object o)
     {
-        // let's go ahead and NPE or CCE if an Integer is not specified
-        return /* (o instanceof Integer) && */ remove(((Integer)o).intValue());
+        // cope with null or non-Integer
+        return (o instanceof Integer) && remove(((Integer)o).intValue());
     }
 
     @Override // from AbstractSet<Integer>