Java 反射

package com.reflect;

import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;

public class Test {
    /**
     * Class 所有类的类类型
     * getMethods 取public方法
     * getDeclaredMethods() 取自身的所有方法包括(private 等)
     * @param args
     */
    public static void main(String[] args) {
        Class c = Student.class;
        
        //构造函数
        Constructor [] cons = c.getConstructors();
        for (Constructor constructor : cons) {
            Class[] params = constructor.getParameterTypes();
            System.out.print(constructor.getName()+"(");
            for (int i = 0; i < params.length; i++) {
                System.out.print(params[i].getName()+",");
            }
            System.out.println(")");
        }
        System.out.println("===================================");
        
        //方法
        Method[] m  = c.getMethods();
        for (Method method : m) {
            Class[] params = method.getParameterTypes();
            System.out.print(method.getReturnType().getName() + " " +method.getName()+"(");
            for (int i = 0; i < params.length; i++) {
                System.out.print(params[i].getName()+",");
            }
            System.out.println(")");
        }
        System.out.println("===================================");
        
        //字段
        Field[] f = c.getDeclaredFields();
        for (Field field : f) {
            System.out.println(field.getType().getName() + " " +field.getName());
        }
        
        try {
            //单个方法的调用
            Student s = new Student();
            Method method = c.getMethod("sayHello", new Class[]{});
            method.invoke(s);
            
            //单个字段的取值
            请看下面的Field使用,个人觉得写的不错
        } catch (Exception e) {
            e.printStackTrace();
        } 
    }
}