반사 메커니즘을 운용하여 대상의 속성 값을 바꾸다

package com.cloud.reflect;

public class ReflectBean {
	private String name;
	private String password;
	private int age;
	
	public ReflectBean(String name, String password) {
		super();
		this.name = name;
		this.password = password;
	}
	
	public String getName() {
		return name;
	}
	
	public void setName(String name) {
		this.name = name;
	}
	
	public String getPassword() {
		return password;
	}
	
	public void setPassword(String password) {
		this.password = password;
	}
	
	public int getAge() {
		return age;
	}
	
	public void setAge(int age) {
		this.age = age;
	}

	@Override
	public String toString() {
		return this.name + ":::" + this.password;
	}
}

package com.cloud.reflect;

import java.lang.reflect.Field;

public class ReflectTest {
	
	public static void main(String[] args) throws Exception {
		ReflectBean reflect = new ReflectBean("chris", "cloud");
		
		changeFieldValue(reflect);
		
		System.out.println(reflect.toString());
	}
	
	public static void changeFieldValue(Object obj) throws Exception {
		Field[] fields = obj.getClass().getDeclaredFields();
		for (Field field : fields) {
			// private ， ， “ ” 
			field.setAccessible(true);
			// “==” ， 
			if (field.getType() == String.class) {
				String oldStr = (String) field.get(obj);
				if (!"cloud".equals(oldStr)) {
					field.set(obj, "cloud");
				}
			}
		}
	}
}