/*

  * Licensed to the Apache Software Foundation (ASF) under one

  * or more contributor license agreements.  See the NOTICE file

  * distributed with this work for additional information

  * regarding copyright ownership.  The ASF licenses this file

  * to you under the Apache License, Version 2.0 (the

  * "License"); you may not use this file except in compliance

  * with the License.  You may obtain a copy of the License at

  *

  *   http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing,

  * software distributed under the License is distributed on an

  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

  * KIND, either express or implied.  See the License for the

  * specific language governing permissions and limitations

  * under the License.

  */

 package org.apache.myfaces.view.facelets.el;

 import java.io.Externalizable;

 import java.io.IOException;

 import java.io.ObjectInput;

 import java.io.ObjectOutput;

 import java.lang.reflect.Method;

 import java.util.HashMap;

 import java.util.Map;

 import javax.el.FunctionMapper;

 import org.apache.myfaces.view.facelets.util.ReflectionUtil;

 /**

  * Default implementation of the FunctionMapper

  * 

  * @see java.lang.reflect.Method

  * @see javax.el.FunctionMapper

  * 

  * @author Jacob Hookom

  * @version $Id$

  */

 public final class DefaultFunctionMapper extends FunctionMapper implements Externalizable

 {

     private static final long serialVersionUID = 1L;

     private Map<String, Function> _functions = null;

     /*

      * (non-Javadoc)

      * 

      * @see javax.el.FunctionMapper#resolveFunction(java.lang.String, java.lang.String)

      */

     public Method resolveFunction(String prefix, String localName)

     {

         if (_functions != null)

         {

             Function f = (Function) _functions.get(prefix + ":" + localName);

             return f.getMethod();

         }

         return null;

     }

     public void addFunction(String prefix, String localName, Method m)

     {

         if (_functions == null)

         {

             _functions = new HashMap<String, Function>();

         }

         Function f = new Function(prefix, localName, m);

         synchronized (this)

         {

             _functions.put(prefix + ":" + localName, f);

         }

     }

     /*

      * (non-Javadoc)

      * 

      * @see java.io.Externalizable#writeExternal(java.io.ObjectOutput)

      */

     public void writeExternal(ObjectOutput out) throws IOException

     {

         out.writeObject(_functions);

     }

     /*

      * (non-Javadoc)

      * 

      * @see java.io.Externalizable#readExternal(java.io.ObjectInput)

      */

     @SuppressWarnings("unchecked")

     public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException

     {

         _functions = (Map<String, Function>) in.readObject();

     }

     @Override

     public String toString()

     {

         StringBuffer sb = new StringBuffer(128);

         sb.append("FunctionMapper[\n");

         for (Function function : _functions.values())

         {

             sb.append(function).append('\n');

         }

         sb.append(']');

         return sb.toString();

     }

     private static class Function implements Externalizable

     {

         private static final long serialVersionUID = 1L;

         protected transient Method _m;

         protected String _owner;

         protected String _name;

         protected String[] _types;

         protected String _prefix;

         protected String _localName;

         /**

          * 

          */

         public Function(String prefix, String localName, Method m)

         {

             if (localName == null)

             {

                 throw new NullPointerException("LocalName cannot be null");

             }

             if (m == null)

             {

                 throw new NullPointerException("Method cannot be null");

             }

             _prefix = prefix;

             _localName = localName;

             _m = m;

         }

         public Function()

         {

             // for serialization

         }

         /*

          * (non-Javadoc)

          * 

          * @see java.io.Externalizable#writeExternal(java.io.ObjectOutput)

          */

         public void writeExternal(ObjectOutput out) throws IOException

         {

             out.writeUTF(_prefix != null ? _prefix : "");

             out.writeUTF(_localName);

             out.writeUTF(_m.getDeclaringClass().getName());

             out.writeUTF(_m.getName());

             out.writeObject(ReflectionUtil.toTypeNameArray(this._m.getParameterTypes()));

         }

         /*

          * (non-Javadoc)

          * 

          * @see java.io.Externalizable#readExternal(java.io.ObjectInput)

          */

         public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException

         {

             _prefix = in.readUTF();

             if ("".equals(_prefix))

             {

                 _prefix = null;

             }

             _localName = in.readUTF();

             _owner = in.readUTF();

             _name = in.readUTF();

             _types = (String[]) in.readObject();

         }

         public Method getMethod()

         {

             if (_m == null)

             {

                 try

                 {

                     Class<?> t = ReflectionUtil.forName(_owner);

                     Class<?>[] p = ReflectionUtil.toTypeArray(_types);

                     _m = t.getMethod(_name, p);

                 }

                 catch (Exception e)

                 {

                     e.printStackTrace();

                 }

             }

             return _m;

         }

         public boolean matches(String prefix, String localName)

         {

             if (_prefix != null)

             {

                 if (prefix == null)

                 {

                     return false;

                 }

                 if (!_prefix.equals(prefix))

                 {

                     return false;

                 }

             }

             return _localName.equals(localName);

         }

         /*

          * (non-Javadoc)

          * 

          * @see java.lang.Object#equals(java.lang.Object)

          */

         @Override

         public boolean equals(Object obj)

         {

             if (obj instanceof Function)

             {

                 return hashCode() == obj.hashCode();

             }

             return false;

         }

         /*

          * (non-Javadoc)

          * 

          * @see java.lang.Object#hashCode()

          */

         @Override

         public int hashCode()

         {

             return (_prefix + _localName).hashCode();

         }

         @Override

         public String toString()

         {

             StringBuffer sb = new StringBuffer(32);

             sb.append("Function[");

             if (_prefix != null)

             {

                 sb.append(_prefix).append(':');

             }

             sb.append(_name).append("] ");

             sb.append(_m);

             return sb.toString();

         }

     }

 }