Merge pull request mongodb#55 from wfreeman/master

This adds $and support to QueryBuilder, along with a simple test.

Author: Brendan W. McAdams

src/main/com/mongodb/QueryBuilder.java

@@ -278,6 +278,23 @@ public QueryBuilder or( DBObject ... ors ){
         return this;
     }
 
+    /**
+     * Equivalent to an $and operand
+     * @param ands
+     * @return
+     */
+    @SuppressWarnings("unchecked")
+    public QueryBuilder and( DBObject ... ands ){
+        List l = (List)_query.get( "$and" );
+        if ( l == null ){
+            l = new ArrayList();
+            _query.put( "$and" , l );
+        }
+        for ( DBObject o : ands )
+            l.add( o );
+        return this;
+    }
+
     /**
      * Creates a <code>DBObject</code> query to be used for the driver's find operations
      * @return Returns a DBObject query instance

src/test/com/mongodb/QueryBuilderTest.java

@@ -291,6 +291,22 @@ public void testOr() {
 
         assertEquals( 2 , c.find( q ).itcount() );
     }
+
+    @Test
+    public void testAnd() {
+        DBCollection c = _testDB.getCollection( "and1" );
+        c.drop();
+        c.insert( new BasicDBObject( "a" , 1 ).append( "b" , 1) );
+        c.insert( new BasicDBObject( "b" , 1 ) );
+        
+        DBObject q = QueryBuilder.start()
+            .and( new BasicDBObject( "a" , 1 ) , 
+                  new BasicDBObject( "b" , 1 ) )
+            .get();
+        
+        assertEquals( 1 , c.find( q ).itcount() );
+    }
+
 
     @AfterClass
     public static void tearDown() {