src/main/java/org/apache/commons/ognl/MapPropertyAccessor.java

package org.apache.commons.ognl;

/*
 * 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.
 */

import java.util.Collection;
import java.util.Map;
import java.util.Set;

/**
 * Implementation of PropertyAccessor that sets and gets properties by storing and looking up values in Maps.
 *
 * $Id$
 */
public class MapPropertyAccessor
    implements PropertyAccessor
{

    public Object getProperty( Map<String, Object> context, Object target, Object name )
        throws OgnlException
    {
        Object result;
        @SuppressWarnings( "unchecked" ) // checked by the invoker
            Map<Object, Object> map = (Map<Object, Object>) target;
        Node currentNode = ( (OgnlContext) context ).getCurrentNode().jjtGetParent();
        boolean indexedAccess = false;

        if ( currentNode == null )
        {
            throw new OgnlException( "node is null for '" + name + "'" );
        }
        if ( !( currentNode instanceof ASTProperty ) )
        {
            currentNode = currentNode.jjtGetParent();
        }
        if ( currentNode instanceof ASTProperty )
        {
            indexedAccess = ( (ASTProperty) currentNode ).isIndexedAccess();
        }

        if ( ( name instanceof String ) && !indexedAccess )
        {
            if ( "size".equals( name ) )
            {
                result = map.size();
            }
            else if ( "keys".equals( name ) || "keySet".equals( name ) )
            {
                result = map.keySet();
            }
            else if ( "values".equals( name ) )
            {
                result = map.values();
            }
            else if ( "isEmpty".equals( name ) )
            {
                result = map.isEmpty() ? Boolean.TRUE : Boolean.FALSE;
            }
            else
            {
                result = map.get( name );
            }
        }
        else
        {
            result = map.get( name );
        }

        return result;
    }

    public void setProperty( Map<String, Object> context, Object target, Object name, Object value )
        throws OgnlException
    {
        @SuppressWarnings( "unchecked" ) // checked by the invoker
        Map<Object, Object> map = (Map<Object, Object>) target;
        map.put( name, value );
    }

    public String getSourceAccessor( OgnlContext context, Object target, Object index )
    {
        Node currentNode = context.getCurrentNode().jjtGetParent();
        boolean indexedAccess = false;

        if ( currentNode == null )
        {
            throw new RuntimeException( "node is null for '" + index + "'" );
        }

        if ( !( currentNode instanceof ASTProperty ) )
        {
            currentNode = currentNode.jjtGetParent();
        }

        if ( currentNode instanceof ASTProperty )
        {
            indexedAccess = ( (ASTProperty) currentNode ).isIndexedAccess();
        }

        String indexStr = index.toString();

        context.setCurrentAccessor( Map.class );
        context.setCurrentType( Object.class );

        if ( String.class.isInstance( index ) && !indexedAccess )
        {
            String key = indexStr.replace( "\"", "" );

            if ( "size".equals( key ) )
            {
                context.setCurrentType( int.class );
                return ".size()";
            }
            if ( "keys".equals( key ) || "keySet".equals( key ) )
            {
                context.setCurrentType( Set.class );
                return ".keySet()";
            }
            if ( "values".equals( key ) )
            {
                context.setCurrentType( Collection.class );
                return ".values()";
            }
            if ( "isEmpty".equals( key ) )
            {
                context.setCurrentType( boolean.class );
                return ".isEmpty()";
            }
        }

        return ".get(" + indexStr + ")";
    }

    public String getSourceSetter( OgnlContext context, Object target, Object index )
    {
        context.setCurrentAccessor( Map.class );
        context.setCurrentType( Object.class );

        String indexStr = index.toString();

        if ( String.class.isInstance( index ) )
        {
            String key = indexStr.replace( "\"", "" );

            if ( "size".equals( key ) || "keys".equals( key ) || "keySet".equals( key ) || "values".equals( key )
                || "isEmpty".equals( key ) )
            {
                return "";
            }
        }

        return ".put(" + indexStr + ", $3)";
    }
}