Java映射

1.Student类

 package com.zdsofe.javaweb.lianxi1;

 public class Student {
   public String stuName;
   private String sex;
   private int age;

 public String getStuName() {
     return stuName;
 }
 public void setStuName(String stuName) {
     this.stuName = stuName;
 }
 public String getSex() {
     return sex;
 }
 public void setSex(String sex) {
     this.sex = sex;
 }
 public int getAge() {
     return age;
 }
 public void setAge(int age) {
     this.age = age;
 }

 public Student(String stuName, int age) {
     super();
     this.stuName = stuName;
     this.age = age;
 }
 public Student(String stuName, String sex) {
     super();
     this.stuName = stuName;
     this.sex = sex;
 }
 public Student() {

 }
   public String tostring()
   {
       return "姓名为："+this.stuName+",性别为："+this.sex;
   }
 }

2.测试类

 package com.zdsofe.javaweb.lianxi1;

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

 public class Test {

  public static void main(String[] args) throws Exception {
         /*//获取class对象的方法一
         Student stu=new Student();
         Class<?>class1=stu.getClass();
         System.out.println(class1);

         //获取class对象的方法二(获得这个包下的这个类的地址)
         Class<?> class2=Class.forName("com.zdsofe.javaweb.lianxi1.Student");
         System.out.println(class2);

         //获取class对象的方法二
         Class<?> class3=Student.class;
         System.out.println(class3.getSimpleName());

         //获得类的public类型属性
         Field[] pb=class3.getFields();
         System.out.println(pb.length);

         //获得类的所有属性
         Field[] pb1=class3.getDeclaredFields();
         System.out.println(pb1.length);

         //获得类的public方法(继承自object类的方法也计算在内)
         Method[]a=class3.getMethods();
         System.out.println(a.length);
         for(Method i:a)
         {
             System.out.println(i);
         }

         //获得类的所有方法（当前类下的方法）
         Method[]a1=class3.getDeclaredMethods();
         System.out.println(a1.length);

         //获得类的public构造方法
         Class<?> cla=Student.class;
         Constructor<?>[] c=cla.getConstructors();
         System.out.println(c);

         //获得所有的构造方法
         Constructor<?>[] c1=cla.getDeclaredConstructors();
         System.out.println(c1);
             */
     /*    //获取Student类对应的class对象
         Class<?> cls=Student.class;

         //获取Student类的无参构造方法对应的Constructor对象
         Constructor<?> c1=cls.getConstructor();

         //获取Student类的有参构造方法对应的Constructor对象
         Constructor<?> c2=cls.getConstructor(String.class,String.class);
         System.out.println(c2);

         //调用Class对象的newInstance()方法创建Student对象
         Student stu1=(Student)cls.newInstance();
         System.out.println(stu1.tostring());

         //调用Constructor对象的newInstance()方法创建Student对象(无参)
         Student stu2=(Student)c1.newInstance();
         System.out.println(stu2.tostring());
         //调用Constructor对象的newInstance()方法创建Student对象(有参)
         Student stu3=(Student)c2.newInstance("张三","女");
         System.out.println(stu3.tostring());*/

        /* //获取Student类对应的class对象
          Class<?> cls=Student.class;
          //通过Student的无参构造方法来创建Student对象
          Object obj= cls.newInstance();
          //获取到stuName对应的Field对象
          Field f1=cls.getField("stuName");
          //调用Field对象的set方法为对象的stuName属性赋值
          f1.set(obj, "张三");
          //获取私有变量对应的Field的对象
          Field f2=cls.getDeclaredField("sex");
          //sex是私有的，所以要通过反射机制访问该变量
          f2.setAccessible(true);
          f2.set(obj, "女");
          //获取到obj的属性值
          Object result1= f2.get(obj);
          Object result2=f1.get(obj);
          System.out.println(result1+":"+result2);
          Student stu=(Student)obj;
          System.out.println(stu.getStuName()+":"+stu.getSex());*/

          //获取Student类对应的class对象
          Class<?> cls=Student.class;
          //通过方法名和方法的参数类型来获取Student类的public方法
          Method m1= cls.getMethod("setStuName", String.class);
          Method m2=cls.getMethod("setSex",String.class);
          String name=m1.getName();
          System.out.println(name);

     }
 }