本文介绍了Java利用Redis实现消息队列的示例代码，分享给大家，具体如下：
应用场景
为什么要用redis?
二进制存储、java序列化传输、IO连接数高、连接频繁
一、序列化
这里编写了一个java序列化的工具,主要是将对象转化为byte数组,和根据byte数组反序列化成java对象; 主要是用到了ByteArrayOutputStream和ByteArrayInputStream; 注意:每个需要序列化的对象都要实现Serializable接口;
其代码如下:
package Utils;
import java.io.*;
/**
* Created by Kinglf on 2016/10/17.
*/
public class ObjectUtil {
/**
* 对象转byte[]
* @param obj
* @return
* @throws IOException
*/
public static byte[] object2Bytes(Object obj) throws IOException{
ByteArrayOutputStream bo=new ByteArrayOutputStream();
ObjectOutputStream oo=new ObjectOutputStream(bo);
oo.writeObject(obj);
byte[] bytes=bo.toByteArray();
bo.close();
oo.close();
return bytes;
}
/**
* byte[]转对象
* @param bytes
* @return
* @throws Exception
*/
public static Object bytes2Object(byte[] bytes) throws Exception{
ByteArrayInputStream in=new ByteArrayInputStream(bytes);
ObjectInputStream sIn=new ObjectInputStream(in);
return sIn.readObject();
}
}
二、消息类(实现Serializable接口)
package Model;
import java.io.Serializable;
/**
* Created by Kinglf on 2016/10/17.
*/
public class Message implements Serializable {
private static final long serialVersionUID = -389326121047047723L;
private int id;
private String content;
public Message(int id, String content) {
this.id = id;
this.content = content;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getContent() {
return content;
}
public void setContent(String content) {
this.content = content;
}
}
三、Redis的操作
利用redis做队列,我们采用的是redis中list的push和pop操作;
结合队列的特点:
只允许在一端插入新元素只能在队列的尾部FIFO:先进先出原则 Redis中lpush头入(rpop尾出)或rpush尾入(lpop头出)可以满足要求,而Redis中list药push或 pop的对象仅需要转换成byte[]即可
java采用Jedis进行Redis的存储和Redis的连接池设置
上代码:
package Utils;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;
import java.util.List;
import java.util.Map;
import java.util.Set;
/**
* Created by Kinglf on 2016/10/17.
*/
public class JedisUtil {
private static String JEDIS_IP;
private static int JEDIS_PORT;
private static String JEDIS_PASSWORD;
private static JedisPool jedisPool;
static {
//Configuration自行写的配置文件解析类,继承自Properties
Configuration conf=Configuration.getInstance();
JEDIS_IP=conf.getString("jedis.ip","127.0.0.1");
JEDIS_PORT=conf.getInt("jedis.port",6379);
JEDIS_PASSWORD=conf.getString("jedis.password",null);
JedisPoolConfig config=new JedisPoolConfig();
config.setMaxActive(5000);
config.setMaxIdle(256);
config.setMaxWait(5000L);
config.setTestOnBorrow(true);
config.setTestOnReturn(true);
config.setTestWhileIdle(true);
config.setMinEvictableIdleTimeMillis(60000L);
config.setTimeBetweenEvictionRunsMillis(3000L);
config.setNumTestsPerEvictionRun(-1);
jedisPool=new JedisPool(config,JEDIS_IP,JEDIS_PORT,60000);
}
/**
* 获取数据
* @param key
* @return
*/
public static String get(String key){
String value=null;
Jedis jedis=null;
try{
jedis=jedisPool.getResource();
value=jedis.get(key);
}catch (Exception e){
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
}finally {
close(jedis);
}
return value;
}
private static void close(Jedis jedis) {
try{
jedisPool.returnResource(jedis);
}catch (Exception e){
if(jedis.isConnected()){
jedis.quit();
jedis.disconnect();
}
}
}
public static byte[] get(byte[] key){
byte[] value = null;
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
value = jedis.get(key);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
return value;
}
public static void set(byte[] key, byte[] value) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.set(key, value);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
}
public static void set(byte[] key, byte[] value, int time) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.set(key, value);
jedis.expire(key, time);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
}
public static void hset(byte[] key, byte[] field, byte[] value) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.hset(key, field, value);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
}
public static void hset(String key, String field, String value) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.hset(key, field, value);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
}
/**
* 获取数据
*
* @param key
* @return
*/
public static String hget(String key, String field) {
String value = null;
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
value = jedis.hget(key, field);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
return value;
}
/**
* 获取数据
*
* @param key
* @return
*/
public static byte[] hget(byte[] key, byte[] field) {
byte[] value = null;
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
value = jedis.hget(key, field);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
return value;
}
public static void hdel(byte[] key, byte[] field) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.hdel(key, field);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
}
/**
* 存储REDIS队列 顺序存储
* @param key reids键名
* @param value 键值
*/
public static void lpush(byte[] key, byte[] value) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.lpush(key, value);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
}
/**
* 存储REDIS队列 反向存储
* @param key reids键名
* @param value 键值
*/
public static void rpush(byte[] key, byte[] value) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.rpush(key, value);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
}
/**
* 将列表 source 中的最后一个元素(尾元素)弹出，并返回给客户端
* @param key reids键名
* @param destination 键值
*/
public static void rpoplpush(byte[] key, byte[] destination) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.rpoplpush(key, destination);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
}
/**
* 获取队列数据
* @param key 键名
* @return
*/
public static List lpopList(byte[] key) {
List list = null;
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
list = jedis.lrange(key, 0, -1);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
return list;
}
/**
* 获取队列数据
* @param key 键名
* @return
*/
public static byte[] rpop(byte[] key) {
byte[] bytes = null;
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
bytes = jedis.rpop(key);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
return bytes;
}
public static void hmset(Object key, Map hash) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.hmset(key.toString(), hash);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
}
public static void hmset(Object key, Map hash, int time) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.hmset(key.toString(), hash);
jedis.expire(key.toString(), time);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
}
public static List hmget(Object key, String... fields) {
List result = null;
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
result = jedis.hmget(key.toString(), fields);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
return result;
}
public static Set hkeys(String key) {
Set result = null;
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
result = jedis.hkeys(key);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
return result;
}
public static List lrange(byte[] key, int from, int to) {
List result = null;
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
result = jedis.lrange(key, from, to);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
return result;
}
public static Map hgetAll(byte[] key) {
Map result = null;
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
result = jedis.hgetAll(key);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
return result;
}
public static void del(byte[] key) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.del(key);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
}
public static long llen(byte[] key) {
long len = 0;
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.llen(key);
} catch (Exception e) {
//释放redis对象
jedisPool.returnBrokenResource(jedis);
e.printStackTrace();
} finally {
//返还到连接池
close(jedis);
}
return len;
}
}
四、Configuration主要用于读取Redis的配置信息
package Utils;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
/**
* Created by Kinglf on 2016/10/17.
*/
public class Configuration extends Properties {
private static final long serialVersionUID = -2296275030489943706L;
private static Configuration instance = null;
public static synchronized Configuration getInstance() {
if (instance == null) {
instance = new Configuration();
}
return instance;
}
public String getProperty(String key, String defaultValue) {
String val = getProperty(key);
return (val == null || val.isEmpty()) ? defaultValue : val;
}
public String getString(String name, String defaultValue) {
return this.getProperty(name, defaultValue);
}
public int getInt(String name, int defaultValue) {
String val = this.getProperty(name);
return (val == null || val.isEmpty()) ? defaultValue : Integer.parseInt(val);
}
public long getLong(String name, long defaultValue) {
String val = this.getProperty(name);
return (val == null || val.isEmpty()) ? defaultValue : Integer.parseInt(val);
}
public float getFloat(String name, float defaultValue) {
String val = this.getProperty(name);
return (val == null || val.isEmpty()) ? defaultValue : Float.parseFloat(val);
}
public double getDouble(String name, double defaultValue) {
String val = this.getProperty(name);
return (val == null || val.isEmpty()) ? defaultValue : Double.parseDouble(val);
}
public byte getByte(String name, byte defaultValue) {
String val = this.getProperty(name);
return (val == null || val.isEmpty()) ? defaultValue : Byte.parseByte(val);
}
public Configuration() {
InputStream in = ClassLoader.getSystemClassLoader().getResourceAsStream("config.xml");
try {
this.loadFromXML(in);
in.close();
} catch (IOException ioe) {
}
}
}
五、测试
import Model.Message;
import Utils.JedisUtil;
import Utils.ObjectUtil;
import redis.clients.jedis.Jedis;
import java.io.IOException;
/**
* Created by Kinglf on 2016/10/17.
*/
public class TestRedisQueue {
public static byte[] redisKey = "key".getBytes();
static {
try {
init();
} catch (IOException e) {
e.printStackTrace();
}
}
private static void init() throws IOException {
for (int i = 0; i < 1000000; i++) {
Message message = new Message(i, "这是第" + i + "个内容");
JedisUtil.lpush(redisKey, ObjectUtil.object2Bytes(message));
}
}
public static void main(String[] args) {
try {
pop();
} catch (Exception e) {
e.printStackTrace();
}
}
private static void pop() throws Exception {
byte[] bytes = JedisUtil.rpop(redisKey);
Message msg = (Message) ObjectUtil.bytes2Object(bytes);
if (msg != null) {
System.out.println(msg.getId() + "----" + msg.getContent());
}
}
}
每执行一次pop()方法,结果如下:
1----这是第1个内容
2----这是第2个内容
3----这是第3个内容
4----这是第4个内容
总结
至此,整个Redis消息队列的生产者和消费者代码已经完成
1.Message 需要传送的实体类(需实现Serializable接口)
2.Configuration Redis的配置读取类,继承自Properties
3.ObjectUtil 将对象和byte数组双向转换的工具类
4.Jedis 通过消息队列的先进先出(FIFO)的特点结合Redis的list中的push和pop操作进行封装的工具类
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。