Java中类的加载机制和反射相关概念

class People {
    private String str = "People";
    private static final String VALUE = "I am people static VALUE";
    public People() {
        System.out.println("people 无参实例化");
    }
    public People(String str) {
        this.str = str;
        System.out.println("people 全参实例化");
    }
    static {
        //System.out.println(str);编译错误
        System.out.println(VALUE);
        System.out.println("I am people static part");
    }
    {
        System.out.println("I am people no static part");
    }
    public void method1() {
        System.out.println("I am people method1");
    }
}
public class article0604 {
    public static void main(String[] args) {
        People people=new People();
    }
}

class Student extends People {
    private String str = "Student";
    public Student() {
        System.out.println("student 无参实例化");
    }
    public Student(String str) {
        this.str = str;
        System.out.println("student 全参实例化");
    }
    static {
        System.out.println("I am student static part");
    }
    {
        System.out.println("I am student no static part");
    }
    @Override
    public void method1() {
        System.out.println("I am student method1");
    }
}
public class article0604 {
    public static void main(String[] args)  {
        Student student = new Student();
    }
}

Class<?> clazz = Class.forName("test0604.Student");
Field[] fields = clazz.getFields();
System.out.println("参数个数：" + fields.length);
for (Field field : fields) {
    System.out.println(field);
}

public static void main(String[] args) throws ClassNotFoundException, NoSuchFieldException {
        Class<?> clazz = Class.forName("test0604.Student");
        //获取参数
        Field[] fields = clazz.getFields();
        Field[] declaredFields = clazz.getDeclaredFields();
        /*
        clazz.getDeclaredMethods()
        反映由这个class对象表示的类或接口声明的所有字段。 这包括公共、受保护、默认(包)访问和私有字段，但不包括继承字段。
         */
        Method[] declaredMethods = clazz.getDeclaredMethods();
        Method[] methods = clazz.getMethods();
        System.out.println("Declared方法：" + declaredMethods.length);
        System.out.println("public方法：" + methods.length);
        System.out.println("Declared参数：" + declaredFields.length);
        System.out.println("public参数：" + fields.length);
        System.out.println("遍历fields：");
        for (Field field : fields) {
            System.out.println(field);
        }
        System.out.println("遍历declaredFields：");
        for (Field field : declaredFields) {
            System.out.println(field);
        }
        System.out.println("遍历declaredMethods：");
        for (Method d : declaredMethods) {
            System.out.println(d);
        }
        System.out.println("遍历methods：");
        for (Method d : methods) {
            System.out.println(d);
        }