Java implements method call through reflection

• Code Implementation

package me.andy.practice.reflect;import org.junit.Test;import java.lang.reflect.Constructor;import java.lang.reflect.Method;import static junit.framework.Assert.assertEquals;public class MethodInvokeTest {    @Test    public void test_add() throws Exception {        Class<?> personClass = Calculate.class;        Object person = personClass.newInstance();        Method method = personClass.getDeclaredMethod("add", new Class[]{int.class, int.class});        Object result = method.invoke(person, new Object[]{1, 2});        assertEquals(result, 3);    }    @Test    public void test_subtract() throws Exception {        Class<?> personClass = Calculate.class;        Object person = personClass.newInstance();        Method method = personClass.getDeclaredMethod("subtract", new Class[]{int.class, int.class});        method.setAccessible(true);        Object result = method.invoke(person, new Object[]{2, 1});        assertEquals(result, 1);    }}class Calculate {     public int add(int a, int b) {        return a + b;    }    private int subtract(int a, int b) {        return a - b;    }}

• Code Description

Create object: Object person = personclass. newinstance ();

Method method = personclass. getmethod ("add", new class [] {Int. Class, Int. Class });

Method call: Object result = method. Invoke (person, new object [] {1, 2 });

Private access method: method. setaccessible (true );