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package com.xiaobu.Reflect;import lombok.Data;import java.io.Serializable;/** * @author xiaobu * @version JDK1.8.0_171 * @date on  2021/6/15 19:02 * @description */@Datapublic class Person implements Serializable {
       private static final long serialVersionUID = 7353364411628218048L;    private String name;    private int age;}

package com.xiaobu.Reflect;import lombok.Data;import lombok.SneakyThrows;import java.io.Serializable;import java.lang.reflect.Field;/** * @author xiaobu * @version JDK1.8.0_171 * @date on  2021/6/15 18:45 * @description */public class ReflectTest {
       @SneakyThrows    public static void main(String[] args) {
           demo2();        getInstance();        demo();    }    @SneakyThrows    public static void demo() {
                  Class
   
     c = Person.class;               //Class
     c = Person.class;        Field f1 = c.getDeclaredField("name");        System.out.println("-----Class.getDeclaredField(String name)用法-------");        System.out.println("-----Class.getDeclaredFields()用法-------");        //通过Class.getDeclaredFields()获取类或接口的指定属性值。        Field[] f2 = c.getDeclaredFields();        for (Field field : f2) {
               field.setAccessible(true);            //Exception in thread "main" java.lang.IllegalArgumentException: Can not set java.lang.String field com.xiaobu.Reflect.ReflectTest$Person.name to java.lang.Class            System.out.println(field.get(c));        }        //修改属性值        System.out.println("----修改name属性------");        f1.setAccessible(true);       //Exception in thread "main" java.lang.IllegalArgumentException: Can not set java.lang.String field com.xiaobu.Reflect.ReflectTest$Person.name to java.lang.Class        f1.set(c, "Maoge");        //修改后再遍历各属性的值        Field[] f3 = c.getDeclaredFields();        for (Field fields : f3) {
               fields.setAccessible(true);            System.out.println(fields.get(c));        }    }    @SneakyThrows    public static void demo2() {
           Person person = new Person();        //通过Class.getDeclaredField(String name)获取类或接口的指定属性值。        Field f1 = Person.class.getDeclaredField("name");        //Field f1 = person.getClass().getDeclaredField("name");        System.out.println("-----Class.getDeclaredField(String name)用法-------");        //System.out.println(f1.get(person));        System.out.println("-----Class.getDeclaredFields()用法-------");        //通过Class.getDeclaredFields()获取类或接口的指定属性值。        Field[] f2 = person.getClass().getDeclaredFields();        for (Field field : f2) {
               field.setAccessible(true);            System.out.println(field.get(person));        }        //修改属性值        System.out.println("----修改name属性------");        f1.setAccessible(true);        f1.set(person, "Maoge");        //修改后再遍历各属性的值        Field[] f3 = person.getClass().getDeclaredFields();        for (Field fields : f3) {
               fields.setAccessible(true);            System.out.println(fields.get(person));        }    }    @SneakyThrows    public static void getInstance() {
           //1. 通过类名获取        Class
    
      p= com.xiaobu.Reflect.Person.class;        //p = class com.xiaobu.Reflect.ReflectTest$Person        System.out.println("p = " + p);        //2. 通过对象实例获取        com.xiaobu.Reflect.Person person = new com.xiaobu.Reflect.Person();        Class
      personClass = person.getClass();        System.out.println(personClass);        //3. 通过Class类静态方法获取        //通过Class类静态方法forName()获取        //Exception in thread "main" java.lang.ClassNotFoundException: com.xiaobu.Reflect.ReflectTest.Person        Class
      c = Class.forName("com.xiaobu.Reflect.ReflectTest.Person");        System.out.println(c);    }    @Data    public static class Person implements Serializable {
           private static final long serialVersionUID = 7353364411628218048L;        private String name;        private int age;    }}
    
   

package com.xiaobu.Reflect;import lombok.SneakyThrows;/** * @author xiaobu * @version JDK1.8.0_171 * @date on  2021/6/15 18:45 * @description */public class ReflectTest2 {
       @SneakyThrows    public static void main(String[] args) {
          getInstance();    }    @SneakyThrows    public static void getInstance() {
           //1. 通过类名获取        Class
   
     p=Person.class;        //p = class com.xiaobu.Reflect.ReflectTest$Person        System.out.println("p = " + p);        //2. 通过对象实例获取        Person person = new Person();        Class
     personClass = person.getClass();        System.out.println(personClass);        //3. 通过Class类静态方法获取        //通过Class类静态方法forName()获取        Class
     c = Class.forName("com.xiaobu.Reflect.Person");        System.out.println(c);    }}
   

1. 可以看出 static的类无法通过Class.forName(“com.xiaobu.Reflect.Person”)来加载出来
2. 类.class 无法给类的属性赋值以及获取值

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