返回自己和超类的 public 字段、方法、构造器
getFields()
getMethods()
getConstructors() 超类没返回

返回自己的所有 字段、方法、构造器
getDeclaredFields()
getDeclaredMethods()
getDeclaredConstructors()

package cn.ycx.common.reflect;

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

/**
 * 类
 *
 * @author: ycx
 * @date: 2022-5-21
 * @since 0.0.1
 */
public class YReflect {
    public static void main(String[] args) throws Exception {
        Class c = Class.forName("cn.ycx.common.reflect.Student");
        System.out.println("自己和超类的");
        // 自己和超类的 public 字段
        Field[] fields = c.getFields();
        for (Field field : fields) {
            System.out.println(field.getName());
        }
        // 自己和超类的 public 方法
        Method[] methods = c.getMethods();
        for (Method method : methods) {
            System.out.println(method.getName());
        }
        // 自己和超类的 Constructor 方法
        Constructor[] constructors = c.getConstructors();
        for (Constructor constructor : constructors) {
            System.out.println(constructor.getName());
        }
        System.out.println("自己的");
        // 自己的 public 字段
        Field[] selfFields = c.getDeclaredFields();
        for (Field field : selfFields) {
            System.out.println(field.getName());
        }
        // 自己的 public 方法
        Method[] selfMethods = c.getDeclaredMethods();
        for (Method method : selfMethods) {
            System.out.println(method.getName());
        }
        // 自己的 Constructor 方法
        Constructor[] selfConstructors = c.getDeclaredConstructors();
        for (Constructor constructor : selfConstructors) {
            System.out.println(constructor.getName());
        }
    }
}
class Person {
    public Person() {}
    public Person(String p) {}
    private String personPrivateField = "personPrivateField";
    protected String personProtectedField = "personProtectedField";
    public String personPublicField = "personPublicField";
    private String personPrivateMethod() {
        System.out.println("personPrivateMethod");
        return "personPrivateMethod";
    }
    protected String personProtectedMethod() {
        System.out.println("personProtectedMethod");
        return "personProtectedMethod";
    }
    public String personPublicMethod() {
        System.out.println("personPublicMethod");
        return "personPublicMethod";
    }
}
class Student extends Person {
    public Student() {}
    public Student(String s) {super(s);}
    private String studentPrivateField = "studentPrivateField";
    protected String studentProtectedField = "studentProtectedField";
    public String studentPublicField = "studentPublicField";
    private String studentPrivateMethod() {
        System.out.println("studentPrivateMethod");
        return "studentPrivateMethod";
    }
    protected String studentProtectedMethod() {
        System.out.println("studentProtectedMethod");
        return "studentProtectedMethod";
    }
    public String studentPublicMethod() {
        System.out.println("studentPublicMethod");
        return "studentPublicMethod";
    }
}