org.apache.commons.jexl.util.GetExecutor Maven / Gradle / Ivy
/*
* 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.jexl.util;
import java.lang.reflect.InvocationTargetException;
import org.apache.commons.logging.Log;
/**
* Executor that simply tries to execute a get(key)
* operation. This will try to find a get(key) method
* for any type of object, not just objects that
* implement the Map interface as was previously
* the case.
*
* @since 1.0
* @author Jason van Zyl
* @version $Id: GetExecutor.java 584046 2007-10-12 05:14:37Z proyal $
*/
public class GetExecutor extends AbstractExecutor {
/**
* Container to hold the 'key' part of
* get(key).
*/
private final Object[] args;
/**
* Default constructor.
*
* @param r The instance log.
* @param ispect The JEXL introspector.
* @param c The class being examined.
* @param key The key for the get(key) operation.
* @throws Exception Failure while trying to obtain the pertinent method.
*/
public GetExecutor(Log r,
org.apache.commons.jexl.util.introspection.Introspector ispect,
Class c, String key) throws Exception {
rlog = r;
// If you passed in null as property, we don't use the value
// for parameter lookup. Instead we just look for get() without
// any parameters.
//
// In any other case, the following condition will set up an array
// for looking up get(String) on the class.
if (key != null)
{
args = new Object[] { key };
} else {
args = null;
}
method = ispect.getMethod(c, "get", args);
}
/**
* {@inheritDoc}
*/
public Object execute(Object o)
throws IllegalAccessException, InvocationTargetException {
if (method == null) {
return null;
}
return method.invoke(o, args);
}
}