多线程如何隔离变量

想传递对象到多线程里的每个线程使用，并且相互之间互不干扰，怎么做？ 

package com.demo.thread;

public class MyBean {
    private int id;
    private String name;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return "MyBean{" +
                "id=" + id +
                ", name='" + name + '\'' +
                '}';
    }
}

import com.demo.thread.MyBean;

public class TestA extends Thread {
    private MyBean myBean;
    public TestA(MyBean myBean){
        this.myBean = myBean;
    }
    @Override
    public void run() {
        System.out.println(Thread.currentThread().getName()+"---"+myBean.getId());
    }
}

import com.demo.thread.MyBean;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class Test {
    public static void main(String[] args) {
        ExecutorService executorService = Executors.newFixedThreadPool(3);
        int i = 0;
        while (i<20) {
            MyBean myBean = new MyBean();
            myBean.setId(i);
            TestA t = new TestA(myBean);
            executorService.execute(t);
            i++;
        }
    }
}

如果这样会出现什么？

 MyBean myBean = new MyBean();
        while (i<20) {