/*
* Copyright 2010, Andrew M Gibson
*
* www.andygibson.net
*
* This file is part of DataValve.
*
* DataValve is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* DataValve is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
*
* You should have received a copy of the GNU Lesser General Public License
* along with DataValve. If not, see <http://www.gnu.org/licenses/>.
*
*/
package org.fluttercode.datavalve.params;
import java.io.Serializable;
import java.lang.reflect.InvocationTargetException;
import org.fluttercode.datavalve.ParameterResolver;
import org.fluttercode.datavalve.provider.ParameterizedDataProvider;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Implementation of a {@link ParameterResolver} that looks up values in the
* referenced object based on run time reflection. The resolver expects a
* parameter to be named as per the JavaBean specification for a particular
* property on the object.
* <p>
* For example, a parameter called name should be specified as
* <code>:name</code> and the property on the object be called
* <code>getName()</code>.
*
* @author Andy Gibson
*
*/
public class ReflectionParameterResolver implements ParameterResolver,Serializable {
private static Logger log = LoggerFactory.getLogger(ReflectionParameterResolver.class);
private static final long serialVersionUID = 1L;
private Object object;
public ReflectionParameterResolver(Object object) {
this.object = object == null ? this : object;
}
public ReflectionParameterResolver() {
this(null);
}
public Object getObject() {
return object;
}
public boolean resolveParameter(ParameterizedDataProvider<? extends Object> dataset,Parameter parameter) {
String name=parameter.getName().substring(1);//remove the starting ':'
String[] properties = name.split("\\.");
int index = 0;
Object base = object;
while (index < properties.length && base != null) {
//log.debug("Resolving property {} on base of {}",properties[index],base);
base = resolveProperty(base, properties[index]);
index++;
}
log.debug("{} resolved to '{}'",parameter.getName(),base);
if (base != null) {
parameter.setValue(base);
return true;
}
return false;
}
public Object resolveProperty(Object base, String property) {
try {
return org.apache.commons.beanutils.PropertyUtils.getProperty(base,
property);
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
return null;
}
public boolean acceptParameter(String parameter) {
return parameter.startsWith(":");
}
}