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/**
* 学生类
* @author snow
*
*/
public class Student {
@StudentName(value="zhangzq")
public String name;
@StudentSchool(value="清华大学")
public String school;
@StudentAge(value=17)
public int age;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getSchool() {
return school;
}
public void setSchool(String school) {
this.school = school;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
@Override
public String toString() {
return "Student [name=" + name + ", school=" + school + ", age=" + age + "]";
}
public Student() {
super();
}
public Student(String name, String school, int age) {
super();
this.name = name;
this.school = school;
this.age = age;
}
}

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Class<?> clazz = Class.forName("com.zzq.reflect.anotation.Student");
// 获取的是public 修饰的公共方法-- 为了区分，我在 Student类里面放了一个 private 的构造方法
Constructor<?>[] constructors = clazz.getConstructors();
for (Constructor<?> constructor : constructors) {
System.out.println( "可以访问到的构造方法：" + constructor.getName() );
}
Constructor<?>[] declaredConstructors = clazz.getDeclaredConstructors();
for (Constructor<?> constructor : declaredConstructors) {
System.out.println( "定义的构造方法：" + constructor );
}

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Class<?> clazz = Class.forName("com.zzq.reflect.anotation.Student");
// 此处如果 Student类里面没有 无参构造则会报错
Student stu = (Student)clazz.newInstance();
stu.setName("zhangzq");
System.out.println( stu );
// 调用指定的构造方法
Constructor<?> c1 = clazz.getDeclaredConstructor(String.class,String.class,int.class);
Student stu1 = (Student)c1.newInstance("zhangzq","清华大学",18);
System.out.println( stu1 );
// 调用私有的构造方法, 两个string 的构造方法，我设置成了 私有的
Constructor<?> c2 = clazz.getDeclaredConstructor(String.class,String.class);
// 因为是私有的，这里不能方法，所以得设置该方法可以访问，设置访问权限为true
// 不设置则会报错
c2.setAccessible(true);
Student stu2 = (Student)c2.newInstance("zhangzq","清华大学");
System.out.println( stu2 );

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Class<?> clazz = Class.forName("com.zzq.reflect.anotation.Student");
Student stu = (Student)clazz.newInstance();
// 获取可以访问的到的字段
Field[] fields = clazz.getFields();
for (Field field : fields) {
System.out.println( "可访问的到的字段：" + field.getName() );
}
// 获取 全部定义的字段
Field[] declaredFields = clazz.getDeclaredFields();
for (Field field : declaredFields) {
System.out.println( "全部定义的字段：" + field.getName() );
}
// 获取指定字段
Field f1 = clazz.getDeclaredField("age");
// 设置可以访问
f1.setAccessible(true);
// 通过 字段的方法进行set值
f1.set(stu,19);
System.out.println( f1.get(stu) );

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Class<?> clazz = Class.forName("com.zzq.reflect.anotation.Student");
Student stu = (Student)clazz.newInstance();
// 获取所有定义的方法，公共方法一样的套路，参考之前的
Method[] declaredMethods = clazz.getDeclaredMethods();
for (Method method : declaredMethods) {
System.out.println( "定义方法：" + method );
}
Method setName = clazz.getDeclaredMethod("setName", String.class);
Method getName = clazz.getDeclaredMethod("getName", null);
// 通过 Method 类的
invoke 方法进行调用该方法
setName.invoke(stu, "zhangzq");
// 动态调用 getName 方法，返回返回值
Object invoke = getName.invoke(stu, null);
System.out.println( invoke );