Redis客户端Redisson使用示例
Redis客户端Redisson使用示例
- Redisson作为Java连接Redis的客户端，提供了连接、操作Redis的方法，还提供分布式锁、红锁等并发工具。Redisson除了提供同步接口外，还提供了异步（Async）、反射式（Reactive）和RxJava2标准的接口。Redisson会序列化Java对象然后保存到redis，所以通过redis命令行设置的值，Redisson来获取值会报错。
- 引入maven依赖包
<dependency>
<groupId>org.redissongroupId>
<artifactId>redissonartifactId>
<version>3.16.0version>
dependency>
- Redisson初始化连接
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;
import org.redisson.Redisson;
import org.redisson.api.*;
import org.redisson.client.RedisClient;
import org.redisson.client.codec.StringCodec;
import org.redisson.codec.JsonJacksonCodec;
import org.redisson.config.Config;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.concurrent.TimeUnit;
import static org.junit.Assert.assertEquals;
@RunWith(Junit4.class)
public class RedissonCase {
private RedissonClient redissonClient;
private RedissonReactiveClient reactiveClient;
private RedissonRxClient rxClient;
@Before
public void init() {
//单节点配置
Config config = new Config();
config.useSingleServer()
.setAddress("redis://localhost:6379")
.setPassword("123456")
.setConnectionPoolSize(5)
.setConnectionMinimumIdleSize(2)
.setDatabase(0);
redissonClient = Redisson.create(config);
reactiveClient = Redisson.createReactive(config);
rxClient = Redisson.createRx(config);
}
@After
public void destroy(){
redissonClient.shutdown();
reactiveClient.shutdown();
rxClient.shutdown();
}
}
- 使用通用对象桶，可以存放任何类型对象
@Test
public void bucket() throws Exception {
//同步
RBucket<String> bucket = redissonClient.getBucket("name");
bucket.set("郑禹");
System.out.println(bucket.get());
//异步
RBucket<String> bucket2 = redissonClient.getBucket("name2");
bucket2.setAsync("刘晓雪").get();
bucket2.getAsync().thenAccept(System.out::println);
//Reactive
RBucketReactive<String> bucket3 = reactiveClient.getBucket("name3");
bucket3.set("张佳慧").block();
bucket3.get().subscribe(System.out::println);
//RxJava2 没有读取到值
RBucketRx<String> bucket4 = rxClient.getBucket("name4");
bucket4.set("刘万敏").blockingSubscribe(System.out::println);
Thread.sleep(1000 * 5);
}
执行结果：
郑禹
刘晓雪
张佳慧
- 清空桶可以给键设置过期时间，或者直接删除键。
@Test
public void clearBucket() {
RBucket<String> bucket = redissonClient.getBucket("name2", new JsonJacksonCodec());
bucket.set("刘晓雪", 60, TimeUnit.SECONDS);
boolean deleteFlag = bucket.delete();
assertEquals(true, deleteFlag);
}
- 流操作
@Test
public void stream() throws Exception {
RBinarySream stream = redissonClient.getBinaryStream("stream");
stream.set("汪稳".getBytes());
OutputStream outputStream = stream.getOutputStream();
outputStream.write("和钱晨馨".getBytes());
InputStream inputStream = stream.getInputStream();
ByteArrayOutputStream result = new ByteArrayOutputStream();
byte[] b = new byte[1024];
int len;
while((len=inputStream.read(b)) != -1) {
result.write(b, 0, len);
}
System.out.println(result.toString());
}
执行结果：
汪稳和钱晨馨
- 原子整型示例，设置初始值10，先自增后返回。
@Test
public void atomicLong() {
RAtomicLong atomicLong = redissonClient.getAtomicLong("atomicLong");
atomicLong.set(10);
atomicLong.incrementAndGet();
System.out.println(atomicLong);
}
执行结果：
11
- 限流器，初始化最大流速，每秒生成5个令牌。
@Test
public void rateLimit() throws Exception {
RRateLimiter rateLimiter = redissonClient.getRateLimiter("rateLimiter");
rateLimiter.trySetRate(RateType.OVERALL, 5, 1, RateIntervalUnit.SECONDS);
for (int i=0;i<10;i++) {
new Thread(new Runnable() {
int i = 0;
@Override
public void run() {
while(true) {
rateLimiter.acquire(1);
System.out.println(Thread.currentThread() + "-" + System.currentTimeMillis() + "-" + i++);
}
}
}).start();
}
Thread.sleep(1000 * 5);
}
执行结果：
Thread[Thread-1,5,main]-1683092928431-0
Thread[Thread-2,5,main]-1683092928434-0
Thread[Thread-4,5,main]-1683092928441-0
Thread[Thread-10,5,main]-1683092928441-0
Thread[Thread-8,5,main]-1683092928442-0
Thread[Thread-10,5,main]-1683092929434-1
Thread[Thread-8,5,main]-1683092929434-1
Thread[Thread-4,5,main]-1683092929434-1
Thread[Thread-10,5,main]-1683092929437-2
Thread[Thread-4,5,main]-1683092929437-2
Thread[Thread-10,5,main]-1683092930449-3
Thread[Thread-1,5,main]-1683092930450-1
Thread[Thread-7,5,main]-1683092930450-0
Thread[Thread-8,5,main]-1683092930450-2
Thread[Thread-2,5,main]-1683092930449-1
Thread[Thread-8,5,main]-1683092931469-3
Thread[Thread-7,5,main]-1683092931471-1
Thread[Thread-5,5,main]-1683092931471-0
Thread[Thread-2,5,main]-1683092931472-2
Thread[Thread-1,5,main]-1683092931472-2
Thread[Thread-8,5,main]-1683092932458-4
Thread[Thread-1,5,main]-1683092932459-3
Thread[Thread-4,5,main]-1683092932461-3
Thread[Thread-5,5,main]-1683092932461-1
Thread[Thread-2,5,main]-1683092932461-3
- 列表操作
@Test
public void list() {
RList<String> list = redissonClient.getList("list");
list.add("big");
list.add("宋茜");
list.add("高圆圆");
list.remove(1);
System.out.println(list);
}
执行结果：
[big, 高圆圆]
- map字典操作
@Test
public void map() {
RMap<String, String> map = redissonClient.getMap("map");
map.put("name", "张飞");
map.put("location", "南京");
map.forEach((key, vlaue) -> {
System.out.println("key=" + key + ",value=" + value);
});
}
执行结果：
key=name,value=张飞
key=location,value=南京
- 元素不可重复set集合
@Test
public void set(){
RSet<String> set = redissonClient.getSet("set");
set.add("汪稳");
set.add("汪新建");
set.forEach(System.out::println);
}
- 队列示例
@Test
public void queue() {
RQueue<String> queue = redissonClient.getQueue("queue");
queue.add("钱晨馨");
queue.add("汪稳");
System.out.println(queue.size() + ":" + queue.poll());
queue.clear();
}
执行结果：
2:钱晨馨
- 可重入锁实现
@Test
public void lock throws InterruptedException {
RLock lock = redissonClient.getLock("lock");
for (int i=0;i<5;i++) {
new Thread(（）-> {
lock.lock();
lock.lock();
try {
System.out.println(Thread.currentThread() + "-" + System.currentTimeMillis() + "-" + "获取了锁");
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
lock.unlock();
}
}).start();
}
Thread.sleep(5000);
}