JavaBean 用反射自己实现简单内省操作 基础

package test;

import java.beans.IntrospectionException;
import java.beans.PropertyDescriptor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

class Point {
private double x;
private double y;

public double getX() {
return x;
}

public void setX(double x) {
this.x = x;
}

public double getY() {
return y;
}

public void setY(double y) {
this.y = y;
}

/**
* @param x
* @param y
*/
public Point(double x, double y) {
super();
this.x = x;
this.y = y;
}
}

public class MainTest {
public static void main(String[] args) throws IllegalArgumentException, IntrospectionException, IllegalAccessException, InvocationTargetException {
Point p = new Point(3, 5);

getProperty(p, "x");
setProperty(p, "y", 10);
}

/**
* @param p
* @param propertyName
* @param value
* @throws IntrospectionException
* @throws IllegalAccessException
* @throws IllegalArgumentException
* @throws InvocationTargetException
*/
public static void setProperty(Object p, String propertyName, Object value)
throws IntrospectionException, IllegalAccessException,
IllegalArgumentException, InvocationTargetException {
PropertyDescriptor pd = new PropertyDescriptor(propertyName, p.getClass());
Method m = pd.getWriteMethod();
m.invoke(p, value);
}

/**
* @param p
* @param propertyName
* @throws IntrospectionException
* @throws IllegalAccessException
* @throws IllegalArgumentException
* @throws InvocationTargetException
*/
public static Object getProperty(Object p, String propertyName)
throws IntrospectionException, IllegalAccessException,
IllegalArgumentException, InvocationTargetException {
PropertyDescriptor pd = new PropertyDescriptor(propertyName, p.getClass());
Method m = pd.getReadMethod();
Object retValue = m.invoke(p);
return retValue;
}
}