Mercurial > jdk8-mips64-public > nashorn / file revision

 /*

  * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions

  * are met:

  *

  *   - Redistributions of source code must retain the above copyright

  *     notice, this list of conditions and the following disclaimer.

  *

  *   - Redistributions in binary form must reproduce the above copyright

  *     notice, this list of conditions and the following disclaimer in the

  *     documentation and/or other materials provided with the distribution.

  *

  *   - Neither the name of Oracle nor the names of its

  *     contributors may be used to endorse or promote products derived

  *     from this software without specific prior written permission.

  *

  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS

  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,

  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR

  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

  */

 import jdk.nashorn.api.scripting.AbstractJSObject;

 import java.nio.DoubleBuffer;

 /**

  * Simple class demonstrating pluggable script object

  * implementation. By implementing jdk.nashorn.api.scripting.JSObject

  * (or extending AbstractJSObject which implements it), you

  * can supply a friendly script object. Nashorn will call

  * 'magic' methods on such a class on 'obj.foo, obj.foo = 33,

  * obj.bar()' etc. from script.

  *

  * In this example, Java nio DoubleBuffer object is wrapped

  * as a friendly script object that provides indexed acces

  * to buffer content and also support array-like "length"

  * readonly property to retrieve buffer's capacity. This class

  * also demonstrates a function valued property called "buf".

  * On 'buf' method, we return the underlying nio buffer object

  * that is being wrapped.

  */

 public class BufferArray extends AbstractJSObject {

     // underlying nio buffer

     private final DoubleBuffer buf;

     public BufferArray(int size) {

         buf = DoubleBuffer.allocate(size);

     }

     public BufferArray(DoubleBuffer buf) {

         this.buf = buf;

     }

     // called to check if indexed property exists

     @Override

     public boolean hasSlot(int index) {

         return index > 0 && index < buf.capacity();

     }

     // get the value from that index

     @Override

     public Object getSlot(int index) {

        return buf.get(index);

     }

     // set the value at that index

     @Override

     public void setSlot(int index, Object value) {

        buf.put(index, ((Number)value).doubleValue());

     }

     // do you have a property of that given name?

     @Override

     public boolean hasMember(String name) {

        return "length".equals(name) || "buf".equals(name);

     }

     // get the value of that named property

     @Override

     public Object getMember(String name) {

        switch (name) {

           case "length":

               return buf.capacity();

           case "buf":

               // return a 'function' value for this property

               return new AbstractJSObject() {

                   @Override

                   public Object call(Object thiz, Object... args) {

                       return BufferArray.this.buf;

                   }

                   // yes, I'm a function !

                   @Override

                   public boolean isFunction() {

                       return true;

                   }

               };

        }

        return null;

     }

 }