Java的反射机制

/**
 * 抽象类--基类
 * */
public abstract class Person {
    
    public abstract String getSex();
    
    public void introduce() {
        System.out.println("I am a person.....");
    }
}
/*******************华丽的分割线***********************/
/**
 * 子类(继承Person类)
 * */
public class Man extends Person {

    private String name = "";
    
    private int age = 0;
    
    @Override
    public String getSex() {
        // TODO Auto-generated method stub
        return "man";
    }

    @Override
    public void introduce() {
        System.out.println("I am a man.....");
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
    
    /**设置为私有*/
    @SuppressWarnings("unused")
    private String say() {
        return "My Name Is " + name + " And I am " + age;
    }
    
    @SuppressWarnings("unused")
    private void setNameAndAge(String name, Integer age) {
        setName(name);
        setAge(age);
    }
}
/*******************华丽的分割线*********************/
/**
 * Java反射操作步骤:
 * 1---获取Class对象
 * 2---获取Class对象的方法反射对象、变量反射对象
 * */
public class ReflectTest {
    
    public static void outputMethod(Class<?> clazz) {
        /**获取Class中的所有的方法(包括继承在父类中继承的方法)*/
        Method [] methods = clazz.getMethods();
        for(Method method : methods ) {
            System.out.println("ALL METHOD : " + method.getName());
        }
        /**获取Class中声明的方法(包括重实现父类的方法)*/
        methods = clazz.getDeclaredMethods();
        for(Method method : methods ) {
            System.out.println("DECLARED METHOD : " + method.getName());
        }
    }
    
    public static Method outputMethod(Class<?> clazz,String name,Class<?> params[]) throws Exception {
        /**获取Class中的声明的具体方法(包括继承在父类中继承的方法)*/
        Method method = clazz.getDeclaredMethod(name, params);
        System.out.println("SPECIFIC DECLARED METHOD : " + method.getName());
        return method;
    }
    
    
    public static void main(String []args) throws Exception {
        ClassLoader loader = Thread.currentThread().getContextClassLoader();
        /**获取Class对象*/
        Class<?> clazz = loader.loadClass("com.qunar.reflect.Man");
        
        /**构造Person对象*/
        Man man = (Man) clazz.newInstance();
        
        /**获取Man的方法的反射对象*/
        ReflectTest.outputMethod(clazz);
        System.out.println("/*********************************/");
        Method method = ReflectTest.outputMethod(clazz, "setNameAndAge", new Class[]{String.class,Integer.class});
        /**允许调用私有方法*/
        method.setAccessible(true);
        method.invoke(man, new Object[]{"张晓龙",28});
        
        method = ReflectTest.outputMethod(clazz, "say", new Class[]{});
        /**允许调用私有方法*/
        method.setAccessible(true);
        String res =  (String) method.invoke(man, new Object[] {});
        System.out.println("Reflect Invoke Result : " + res);
    }
    
}