/*
* Copyright 2002-2006 The Apache Software Foundation.
*
* Licensed 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.jexl.JexlHelper;
import org.apache.commons.jexl.JexlContext;
import org.apache.commons.jexl.Expression;
import org.apache.commons.jexl.ExpressionFactory;
/**
* Simple example to show how to access method and properties.
*
* @since 1.0
* @author <a href="mailto:geirm@apache.org">Geir Magnusson Jr.</a>
* @version $Id: MethodPropertyExample.java 397078 2006-04-26 04:07:54Z dion $
*/
public class MethodPropertyExample {
/**
* Command line entry point.
* @param args Command line arguments
* @throws Exception on any error.
*/
public static void main(String[] args) throws Exception {
/*
* First make a jexlContext and put stuff in it
*/
JexlContext jc = JexlHelper.createContext();
jc.getVars().put("foo", new Foo());
jc.getVars().put("number", new Integer(10));
/*
* access a method w/o args
*/
Expression e = ExpressionFactory.createExpression("foo.getFoo()");
Object o = e.evaluate(jc);
System.out.println("value returned by the method getFoo() is : " + o);
/*
* access a method w/ args
*/
e = ExpressionFactory.createExpression("foo.convert(1)");
o = e.evaluate(jc);
System.out.println("value of " + e.getExpression() + " is : " + o);
e = ExpressionFactory.createExpression("foo.convert(1+7)");
o = e.evaluate(jc);
System.out.println("value of " + e.getExpression() + " is : " + o);
e = ExpressionFactory.createExpression("foo.convert(1+number)");
o = e.evaluate(jc);
System.out.println("value of " + e.getExpression() + " is : " + o);
/*
* access a property
*/
e = ExpressionFactory.createExpression("foo.bar");
o = e.evaluate(jc);
System.out.println("value returned for the property 'bar' is : " + o);
}
/**
* Helper example class.
*/
public static class Foo {
/**
* Gets foo.
* @return a string.
*/
public String getFoo() {
return "This is from getFoo()";
}
/**
* Gets an arbitrary property.
* @param arg property name.
* @return arg prefixed with 'This is the property '.
*/
public String get(String arg) {
return "This is the property " + arg;
}
/**
* Gets a string from the argument.
* @param i a long.
* @return The argument prefixed with 'The value is : '
*/
public String convert(long i) {
return "The value is : " + i;
}
}
}