Commons JXPath example source code file (VariableReference.java)

This example Commons JXPath source code file (VariableReference.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Commons JXPath tags/keywords

expression, expression, object, object, qname, qname, string, variablereference, variablereference

The Commons JXPath VariableReference.java source code

/*
 * 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.commons.jxpath.ri.compiler;

import org.apache.commons.jxpath.ri.QName;
import org.apache.commons.jxpath.ri.EvalContext;

/**
 * An element of the compile tree holding a variable reference.
 *
 * @author Dmitri Plotnikov
 * @version $Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $
 */
public class VariableReference extends Expression {

    private QName varName;

    /**
     * Create a new VariableReference.
     * @param varName variable name
     */
    public VariableReference(QName varName) {
        this.varName = varName;
    }

    /**
     * Get the variable name.
     * @return QName
     */
    public QName getVariableName() {
        return varName;
    }

    public String toString() {
        return "$" + varName;
    }

    public boolean isContextDependent() {
        return false;
    }

    public boolean computeContextDependent() {
        return false;
    }

    public Object compute(EvalContext context) {
        return computeValue(context);
    }

    /**
     * Returns the value of the variable.
     * @param context EvalContext against which to compute the variable's value.
     * @return Object
     */
    public Object computeValue(EvalContext context) {
        return context.getRootContext().getVariableContext(varName);
    }
}