jrempropertyinvoker.java

JRemoteControl is a simple Java&#8482 driven bluetooth remote control.It allows you to initiate virt

/*
 * Copyright (C) 2007 Filippo Di Vattimo - See LICENSE
 *
 */

package fildiv.jremcntl.server.core;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;

import fildiv.jremcntl.common.core.JRemRuntimeException;

public class JRemPropertyInvoker {
	
	public void invokeSet(String propertyName, Object object, Object value) {

		Method m = null;

		try {
			
			String setterName = 
				buildPropertyName(propertyName, "set");

			Class clazz = object.getClass();

			m = clazz.getMethod(setterName, new Class[] { getPrimitive(value
					.getClass()) });
		
		} catch (NoSuchMethodException e) {

			String msg = buildErrorMsg(object.getClass(), propertyName, e);

			throw new JRemRuntimeException(msg, e);
		}

		int mod = m.getModifiers();
		if (!Modifier.isPublic(mod))
			return;
		
		invokeSet(m, object, value);
	}

	public Object invokeGet(String propertyName, Object object) {
		
		// Try with get
		
		try {
			return invokeGet(propertyName, object, "get");
			
		} catch(Exception e) {
			// Ignore
		}

		// Try with get

		return invokeGet(propertyName, object, "is");
	}

	protected Object invokeGet(String propertyName, Object object, String getMethodPrefix) {
		
		Method m = null;

		try {
			
			String getterName = 
				buildPropertyName(propertyName, getMethodPrefix);

			Class clazz = object.getClass();

			m = clazz.getMethod(getterName, new Class[] {} );
		
		} catch (NoSuchMethodException e) {

			String msg = buildErrorMsg(object.getClass(), 
					propertyName, e);

			throw new JRemRuntimeException(msg, e);
		}

		int mod = m.getModifiers();
		if (!Modifier.isPublic(mod))
			throw new IllegalAccessError();
		
		return invokeGet(m, object);
	}
	
	private Object invokeGet(Method m, Object object) {
		assert m != null;
		
		try {
			
			return m.invoke(object , new Object[] { });

		} catch (IllegalAccessException e) {

			String msg = buildErrorMsg(object.getClass(), 
					m.getName(), e);
			
			throw new JRemRuntimeException(msg, e);

		} catch (InvocationTargetException e) {

			String msg = buildErrorMsg(object.getClass(), 
					m.getName(), e);

			throw new JRemRuntimeException(msg, e);
		}
	}

	private void invokeSet(Method m, Object object, Object value) {
		
		assert m != null;
		
		try {
			
			m.invoke(object, new Object[] { value });

		} catch (IllegalAccessException e) {

			String msg = buildErrorMsg(object.getClass(), 
					m.getName(), e);
			
			throw new JRemRuntimeException(msg, e);

		} catch (InvocationTargetException e) {

			String msg = buildErrorMsg(object.getClass(), 
					m.getName(), e);

			throw new JRemRuntimeException(msg, e);
		}
	}

	private String buildPropertyName(String propertyName, String type) {

		StringBuffer sb = new StringBuffer(type);

		sb.append(propertyName.substring(0, 1).toUpperCase());
		sb.append(propertyName.substring(1));

		return sb.toString();
	}

	private Class getPrimitive(Class clazz) {

		if (clazz == Integer.class)
			return int.class;

		if (clazz == Short.class)
			return short.class;

		if (clazz == Boolean.class)
			return boolean.class;

		return clazz;
	}

	private String buildErrorMsg(Class clazz, String propertyName, Exception e) {
		
		String msg = "Error invoking " + propertyName + " on " + clazz.getName() + 
			" has get/is/" + propertyName + " been defined ?";
		
		return msg;
	}

}