/**
* Copyright 2016 Nabarun Mondal
* 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.
*
*/
package com.noga.njexl.lang.examples;
import com.noga.njexl.lang.JexlEngine;
import com.noga.njexl.lang.MapContext;
import com.noga.njexl.lang.Expression;
import com.noga.njexl.lang.JexlContext;
import junit.framework.TestCase;
/**
* Simple example to show how to access method and properties.
*
* @since 1.0
*/
public class MethodPropertyTest extends TestCase {
/**
* An example for method access.
*/
public static void example(final Output out) throws Exception {
/**
* First step is to retrieve an instance of a JexlEngine;
* it might be already existing and shared or created anew.
*/
JexlEngine jexl = new JexlEngine();
/*
* Second make a jexlContext and put stuff in it
*/
JexlContext jc = new MapContext();
/**
* The Java equivalents of foo and number for comparison and checking
*/
Foo foo = new Foo();
Integer number = new Integer(10);
jc.set("foo", foo);
jc.set("number", number);
/*
* access a method w/o args
*/
Expression e = jexl.createExpression("foo.getFoo()");
Object o = e.evaluate(jc);
out.print("value returned by the method getFoo() is : ", o, foo.getFoo());
/*
* access a method w/ args
*/
e = jexl.createExpression("foo.convert(1)");
o = e.evaluate(jc);
out.print("value of " + e.getExpression() + " is : ", o, foo.convert(1));
e = jexl.createExpression("foo.convert(1+7)");
o = e.evaluate(jc);
out.print("value of " + e.getExpression() + " is : ", o, foo.convert(1+7));
e = jexl.createExpression("foo.convert(1+number)");
o = e.evaluate(jc);
out.print("value of " + e.getExpression() + " is : ", o, foo.convert(1+number.intValue()));
/*
* access a property
*/
e = jexl.createExpression("foo.bar");
o = e.evaluate(jc);
out.print("value returned for the property 'bar' is : ", o, foo.get("bar"));
}
/**
* 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;
}
}
/**
* Unit test entry point.
* @throws Exception
*/
public void testExample() throws Exception {
example(Output.JUNIT);
}
/**
* Command line entry point.
* @param args command line arguments
* @throws Exception cos jexl does.
*/
public static void main(String[] args) throws Exception {
example(Output.SYSTEM);
}
}