package fanshe;

 public class Person {

     public String name;

     private String age;

     private int p;

     public Person() {};

     public Person(String name, String age) {

         super();

         this.name = name;

         this.age = age;

     }

     private Person(String name, String age,int p) {

         super();

         this.name = name;

         this.age = age;

         this.p = p;

     }

     public String getName() {

         return name;

     }

     @Override

     public String toString() {

         return "Person [name=" + name + ", age=" + age + "]" + "p -"+ p;

     }

     public void setName(String name) {

         this.name = name;

     }

     public String getAge() {

         return age;

     }

     public void setAge(String age) {

         this.age = age;

     }

 }

 package fanshe;

 import java.lang.reflect.Constructor;

 import java.lang.reflect.Field;

 import java.lang.reflect.InvocationTargetException;

 import java.lang.reflect.Method;

 public class demo1 {

     public static void main(String[] args) {

         // TODO Auto-generated method stub

         try {

             d_3();

         } catch (Exception e) {

             // TODO: handle exception

             e.printStackTrace();

         }

     }

     private static void d_1() {

         Person p = new Person();

         Class  c = p.getClass();

     }

     private static void d_2() {

         Class  c =  Person.class;

           System.out.println(c);

     }

     private static void d_3() throws ClassNotFoundException, NoSuchMethodException, SecurityException, InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, NoSuchFieldException {

         Class  c = Class.forName("fanshe.Person");

         //--------------------------//

         Constructor con = c.getConstructor(); //获得 空参数的构造器 public

         Object o= con.newInstance(); //运行获取到的构造方法

         System.out.println(o.toString());

         //--------------------------//

         Constructor con2 = c.getConstructor(String.class,String.class); //获得带有参数的构造方法 public

         Object o2 = (Person)con2.newInstance("a","22");

         System.out.println(o2.toString());

         //--------------------------//

         Constructor con3 = c.getDeclaredConstructor(String.class,String.class,int.class); //获得带有参数的构造方法 private

         con3.setAccessible(true);

         Object o3 = (Person)con3.newInstance("a","22",14);

         System.out.println(o3.toString());

         //--------------------------//

         Object tmp_obj = c.newInstance();

         Field f_name = c.getField("name");//获得成员变量 public

         f_name.set(tmp_obj, "abc"); //设置变量

         System.out.println(tmp_obj);

         //--------------------------//

         Field f_age = c.getDeclaredField("age");//获得成员变量 public

         System.out.println(f_age);

         //--------------------------//

         Method m_getName = c.getMethod("getName"); //获得类函数无参数 public

         Object o1 = m_getName.invoke(tmp_obj); //运行getName方法.返回值 反给obj

         System.out.println(o1);

         //--------------------------//

         Method m_setName = c.getMethod("setName",String.class);

         m_setName.invoke(tmp_obj,"abcdqweqwe");

         System.out.println(tmp_obj.toString());

     }

 }

 ArrayList<String> arr = new ArrayList<String>();

 arr.add("a");

 Class carr = arr.getClass();

 Method arr_add = carr.getMethod("add",Object.class);

 arr_add.invoke(arr, 1);

 arr_add.invoke(arr, 2);

 arr_add.invoke(arr, 3);

 arr_add.invoke(arr, 4);

 System.out.println(arr);