src/main/java/org/apache/commons/ognl/ASTEval.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 org.apache.commons.ognl.enhance.UnsupportedCompilationException;

/**
 * $Id$
 */
class ASTEval
    extends SimpleNode
{

    public ASTEval( int id )
    {
        super( id );
    }

    public ASTEval( OgnlParser p, int id )
    {
        super( p, id );
    }

    protected Object getValueBody( OgnlContext context, Object source )
        throws OgnlException
    {
        Object result, expr = children[0].getValue( context, source ), previousRoot = context.getRoot();
        Node node;

        source = children[1].getValue( context, source );
        node = ( expr instanceof Node ) ? (Node) expr : (Node) Ognl.parseExpression( expr.toString() );
        try
        {
            context.setRoot( source );
            result = node.getValue( context, source );
        }
        finally
        {
            context.setRoot( previousRoot );
        }
        return result;
    }

    protected void setValueBody( OgnlContext context, Object target, Object value )
        throws OgnlException
    {
        Object expr = children[0].getValue( context, target ), previousRoot = context.getRoot();
        Node node;

        target = children[1].getValue( context, target );
        node = ( expr instanceof Node ) ? (Node) expr : (Node) Ognl.parseExpression( expr.toString() );
        try
        {
            context.setRoot( target );
            node.setValue( context, target, value );
        }
        finally
        {
            context.setRoot( previousRoot );
        }
    }

    public String toGetSourceString( OgnlContext context, Object target )
    {
        throw new UnsupportedCompilationException( "Eval expressions not supported as native java yet." );
    }

    public String toSetSourceString( OgnlContext context, Object target )
    {
        throw new UnsupportedCompilationException( "Map expressions not supported as native java yet." );
    }

    public <R, P> R accept( NodeVisitor<? extends R, ? super P> visitor, P data )
        throws OgnlException
    {
        return visitor.visit( this, data );
    }

    @Override
    public boolean isEvalChain( OgnlContext context )
        throws OgnlException
    {
        return true;
    }
}