J2EE&反射

package com.zking.fanshe;
public class Student {
  private String sid;
  private String sname;
  public Integer age;
  static{
    System.out.println("加载进jvm中！");
  }
  public Student() {
    super();
    System.out.println("调用无参构造方法创建了一个学生对象");
  }
  public Student(String sid) {
    super();
    this.sid = sid;
    System.out.println("调用带一个参数的构造方法创建了一个学生对象");
  }
  public Student(String sid, String sname) {
    super();
    this.sid = sid;
    this.sname = sname;
    System.out.println("调用带二个参数的构造方法创建了一个学生对象");
  }
  @SuppressWarnings("unused")
  private Student(Integer age) {
    System.out.println("调用Student类私有的构造方法创建一个学生对象");
    this.age = age;
  }
  public String getSid() {
    return sid;
  }
  public void setSid(String sid) {
    this.sid = sid;
  }
  public String getSname() {
    return sname;
  }
  public void setSname(String sname) {
    this.sname = sname;
  }
  public void hello() {
    System.out.println("你好！我是" + this.sname);
  }
  public void hello(String name) {
    System.out.println(name + "你好！我是" + this.sname);
  }
  @SuppressWarnings("unused")
  private Integer add(Integer a, Integer b) {
    return new Integer(a.intValue() + b.intValue());
  }
  @Override
  public String toString() {
    return "Student [sid=" + sid + ", sname=" + sname + ", age=" + age + "]";
  }
}

  //1.Class.forname()
  Class stuClass  =Class.forName("com.zking.fanshe.Student");
    //2.类
  Class Class = Student.class;
    //3.对象 .getClass
  Student student = new Student();
  Class class2 = student.getClass();
  System.out.println(stuClass);
  System.out.println(class2);
  System.out.println(Class);

//实例化对象
  Constructor con = stuClass.getConstructor();
  Student stu = (Student) con.newInstance();
  stu.setSid("001");
  stu.setSname("宝宝");
  System.out.println(stu);
  //有参 参数构造
  Constructor con1 = stuClass.getConstructor(String.class,String.class);
  Student stu02 = (Student) con1.newInstance("004","瑶宝");
  System.out.println(stu02);
    //私有方法①
  Constructor<Student> con3 = stuClass.getDeclaredConstructor(Integer.class);
  con3.setAccessible(true);
  Student stu04 = con3.newInstance(18);
  System.out.println(stu04);

    //无参的公共方法
  Method method = stuClass.getMethod("hello");
  method.invoke(stu);
  //有参的公共方法
  Method method2 = stuClass.getMethod("hello", String.class);
  method2.invoke(stu, "辉辉");
  //②
  Method method3 = stuClass.getDeclaredMethod("add", Integer.class,Integer.class);
  method3.setAccessible(true);
  int n = (Integer) method3.invoke(stu, 1,2);
  System.out.println(n);

    //公有反射属性
  Field field = stuClass.getField("age");
  field.set(stu, 98);
  System.out.println(stu);
  //私有反射属性
  Field sname = stuClass.getDeclaredField("sname");
  sname.setAccessible(true);
  sname.set(stu, "小红花");
  System.out.println(stu);