Java多线程分批发送消息的小例子
需求:
假设有10万个用户,现在节假日做活动,需要给每个用户发送一条活动短信,为了提高程序的效率,建议使用多线程分批发送.
这里值得注意的是:
每开一个线程都会占用CPU的资源,所以线程根据所需要的条数来决定就好,避免浪费,我们用的是一个小例子,只是说明了多线程处理提高了效率,实际的大规模场景中不建议使用,可选消息中间件来轮询处理.
Demo示例:
这里为简化展示,模拟示例10条内容,用分页处理的方式来分批发送消息,每批为2条:
结构如下:
entity
|----------- UserEntity
batch
|----------- BatchSms
utils
|----------- ListUtils
相关类如下:
UserEntity:
package entity;
public class UserEntity {
private String userId;
private String userName;
public UserEntity(String userId, String userName) {
this.userId = userId;
this.userName = userName;
}
public String getUserId() {
return userId;
}
public void setUserId(String userId) {
this.userId = userId;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
@Override
public String toString() {
return "UserEntity{" +
"userId='" + userId + '\'' +
", userName='" + userName + '\'' +
'}';
}
}
BatchSms:
package batch;
import entity.UserEntity;
import utils.ListUtils;
import java.util.ArrayList;
import java.util.List;
class UserSendThread implements Runnable {
private List<UserEntity> listUser;
public UserSendThread(List<UserEntity> listUser) {
this.listUser = listUser;
}
public void run() {
for (UserEntity userEntity : listUser) {
System.out.println(Thread.currentThread().getName() + " " + userEntity.toString());
}
}
}
public class BatchSms {
public static void main(String[] args) {
// 1. 初始化数据
List<UserEntity> list = initUser();
// 2.定义每个线程分批发送大小
int userCount = 2;
// 3.计算每个线程需要分批跑的数据
List<List<UserEntity>> splitList = ListUtils.splitList(initUser(), userCount);
for (int i = 0; i < splitList.size(); i++) {
List<UserEntity> list1 = splitList.get(i);
UserSendThread userSendThread = new UserSendThread(list1);
// 4.分批发送
Thread thread = new Thread(userSendThread, "线程" + i);
thread.start();
System.out.println();
}
}
private static List<UserEntity> initUser() {
List<UserEntity> list = new ArrayList<UserEntity>();
for (int i = 0; i < 10; i++) {
list.add(new UserEntity("userid:" + i, "username" + i));
}
return list;
}
}
ListUtils:
package utils;
import java.util.ArrayList;
import java.util.List;
public class ListUtils {
/**
*
* @methodDesc: 功能描述:(list 集合分批切割)
* @param: @param
* list
* @param: @param
* pageSize
* @param: @return
* @returnType:@param list 切割集合
* @returnType:@param pageSize 分页长度
* @returnType:@return List<List<T>> 返回分页数据
*/
static public<T> List<List<T>> splitList(List<T> list, int pageSize) {
int listSize = list.size();
int page = (listSize + (pageSize - 1)) / pageSize;
List<List<T>>listArray = new ArrayList<List<T>>();
for (int i = 0; i<page; i++) {
List<T>subList = new ArrayList<T>();
for (int j = 0; j<listSize; j++) {
int pageIndex = ((j + 1) + (pageSize - 1)) / pageSize;
if (pageIndex == (i + 1)) {
subList.add(list.get(j));
}
if ((j + 1) == ((j + 1) * pageSize)) {
break;
}
}
listArray.add(subList);
}
return listArray;
}
}
启动后运行结果如下: