1.对Redis的Key-Value数据存储操作提供了更高层次的抽象,类似于Spring Framework对JDBC支持一样。
2.如果不用这个你就要自己进行redis连接的连接与关闭操作,这个要小心的进行关闭,因为不关闭连接
就会太多,甚至用完(连接池方式)不能连接
3.RedisTemplate是线程安全的(spring-data-redis的操作接口)
4.ObjectMapper是线程安全的(外部序列化用到的)
spring-data-redis Operations
spring-data-redis针对jedis提供了如下功能:
1. 连接池自动管理,提供了一个高度封装的“RedisTemplate”类
2. 针对jedis客户端中大量api进行了归类封装,将同一类型操作封装为operation接口
ValueOperations:简单K-V操作
SetOperations:set类型数据操作
ZSetOperations:zset类型数据操作
HashOperations:针对map类型的数据操作
ListOperations:针对list类型的数据操作
3. 提供了对key的“bound”(绑定)便捷化操作API,可以通过bound封装指定的key,然后进行一系列的操作而无须“显式”的再次指定Key.
BoundValueOperations
BoundSetOperations
BoundListOperations
BoundSetOperations
BoundHashOperations
两者区别是一个进行set时要写key值(里面可以进行多个key的操作),一个不用(里面只可以进行一个key的操作)
ValueOperations<String, User> valueOper = redisTemplate.opsForValue(); //取得一个新的ValueOperations
Spring-data-redis: serializer(序列化方式)
设置序列化方式(可以用内置的,也可以用别的)
spring-data-redis提供了多种serializer策略,这对使用jedis的开发者而言,实在是非常便捷。sdr提供了4种内置的serializer:
1.JdkSerializationRedisSerializer:使用JDK的序列化手段(serializable接口,ObjectInputStrean,ObjectOutputStream),数据以字节流存储
2.StringRedisSerializer:字符串编码,数据以string存储
3.JacksonJsonRedisSerializer:json格式存储
4.OxmSerializer:xml格式存储
注意:
1.其中JdkSerializationRedisSerializer和StringRedisSerializer是最基础的序列化策略。
2.其中“JacksonJsonRedisSerializer”与“OxmSerializer”都是基于stirng存储,因此它们是较为“高级”的序列化(最终还是使用string解析以及构建java对象)。
RedisTemplate中需要声明4种serializer,默认为“JdkSerializationRedisSerializer”:
1) keySerializer :对于普通K-V操作时,key采取的序列化策略
2) valueSerializer:value采取的序列化策略
3) hashKeySerializer: 在hash数据结构中,hash-key的序列化策略
4) hashValueSerializer:hash-value的序列化策略
注意:无论如何,建议key/hashKey采用StringRedisSerializer。
例子:
redis.properties
# Redis settings redis.host=127.0.0.1 redis.port=6379 redis.pass= redis.maxIdle=300 redis.maxTotal=600 redis.maxWaitMillis=1000 redis.testOnBorrow=true
applicationContext.xml
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:jee="http://www.springframework.org/schema/jee" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <context:annotation-config /> <!-- <task:annotation-driven /> --> <context:component-scan base-package="com.*" /> <context:property-placeholder location="classpath:redis.properties" /> <bean id="poolConfig" class="redis.clients.jedis.JedisPoolConfig"> <property name="maxIdle" value="${redis.maxIdle}" /> <property name="maxTotal" value="${redis.maxTotal}" /> <property name="maxWaitMillis" value="${redis.maxWaitMillis}" /> <property name="testOnBorrow" value="${redis.testOnBorrow}" /> </bean> <bean id="connectionFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory" p:host-name="${redis.host}" p:port="${redis.port}" p:password="${redis.pass}" p:pool-config-ref="poolConfig" /> <bean id="redisTemplate" class="org.springframework.data.redis.core.StringRedisTemplate"> <property name="connectionFactory" ref="connectionFactory" /> <property name="keySerializer"> <bean class="org.springframework.data.redis.serializer.StringRedisSerializer" /> </property> <property name="valueSerializer"> <bean class="org.springframework.data.redis.serializer.JdkSerializationRedisSerializer" /> </property> <!-- <property name="enableTransactionSupport" value="true" /> --> </bean> </beans>
User.java
package com.redis; import java.io.Serializable; public class User implements Serializable{ private static final long serialVersionUID = 1L; private long id; private String name; public long getId() { return id; } public void setId(long id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } @Override public String toString() { return "User [id=" + id + ", name=" + name + "]"; } public User(long id, String name) { super(); this.id = id; this.name = name; } public User() { super(); // TODO Auto-generated constructor stub } }
使用内部JdkSerializationRedisSerializer工具进行序列化
main
package com.redis; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import org.springframework.data.redis.core.RedisTemplate; import org.springframework.data.redis.core.ValueOperations; public class SpringDataRedisTest { public static void main(String[] args) throws InterruptedException { ApplicationContext applicationContext = new ClassPathXmlApplicationContext("classpath:/applicationContext.xml"); RedisTemplate redisTemplate = (RedisTemplate) applicationContext.getBean("redisTemplate"); System.out.println("redisTemplate == " + redisTemplate); ValueOperations<String, User> valueOper = redisTemplate.opsForValue(); User u1 = new User(10, "zhangsan"); User u2 = new User(11, "lisi"); valueOper.set("u:u1", u1); valueOper.set("u:u2", u2); User User = valueOper.get("u:u1"); System.out.println("User == " + User.toString()); User User2 = valueOper.get("u:u2"); System.out.println("User2 == " + User2.toString()); } }
使用外部jackson工具进行序列化
1.因为使用内部的序列化工具创建ValueOperations时要指定对象的ClassType,用外部序列化工具可以全部基于String(接口统一),如
ValueOperations<String, User> valueOper = redisTemplate.opsForValue(); //取得一个新的ValueOperations,要指定User
main
package com.redis; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; public class SpringDataRedisOtherJsonTest { public static void main(String[] args) throws InterruptedException { ApplicationContext applicationContext = new ClassPathXmlApplicationContext("classpath:/applicationContext.xml"); RedisClientTest redisClientTest = (RedisClientTest) applicationContext.getBean("redisClientTest"); System.out.println("redisClientTest == " + redisClientTest); User user1 = new User(); user1.setId(21); user1.setName("obama21"); redisClientTest.insertUser(user1); System.out.println("insertUser"); User user2 = redisClientTest.getUser(21); System.out.println("user2 == " + user2.toString()); } }
JsonRedisSeriaziler.java
package com.redis; import java.io.IOException; import org.codehaus.jackson.JsonGenerationException; import org.codehaus.jackson.JsonParseException; import org.codehaus.jackson.map.JsonMappingException; import org.codehaus.jackson.map.ObjectMapper; import org.springframework.stereotype.Service; @Service("jsonRedisSeriaziler") public class JsonRedisSeriaziler { private ObjectMapper objectMapper = new ObjectMapper(); /** * java-object as json-string * * @param object * @return */ public String seriazileAsString(Object object) { if (object == null) { return null; } try { return this.objectMapper.writeValueAsString(object); } catch (JsonGenerationException e) { e.printStackTrace(); } catch (JsonMappingException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } return null; } /** * json-string to java-object * * @param str * @return */ public <T> T deserializeAsObject(String str, Class<T> clazz) { if (str == null || clazz == null) { return null; } try { return this.objectMapper.readValue(str, clazz); } catch (JsonParseException e) { e.printStackTrace(); } catch (JsonMappingException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } return null; } }
RedisClientTest.java
package com.redis; import javax.annotation.Resource; import org.springframework.data.redis.core.RedisTemplate; import org.springframework.data.redis.core.ValueOperations; import org.springframework.stereotype.Service; @Service("redisClientTest") public class RedisClientTest { @Resource(name = "jsonRedisSeriaziler") private JsonRedisSeriaziler seriaziler; @Resource(name = "redisTemplate") private RedisTemplate redisTemplate; public void insertUser(User user) { ValueOperations<String, String> operations = redisTemplate.opsForValue(); operations.set("user:" + user.getId(), seriaziler.seriazileAsString(user)); } public User getUser(long id) { ValueOperations<String, String> operations = redisTemplate.opsForValue(); String json = operations.get("user:" + id); System.out.println("json ==" + json); return seriaziler.deserializeAsObject(json, User.class); } }
参考原文: http://shift-alt-ctrl.iteye.com/blog/1886831
Spring-data-redis事务
1.enableTransactionSupport:是否启用事务支持。要在XML文件中进行配置(StringRedisTemplate的属性)
2.enableTransactionSupport为true时,系统自动帮我们拿到了事务中绑定的连接。可以在一个方法的多次对Redis增删该查中,始终使用同一个连接。
但是,即使使用了同样的连接,没有进行connection.multi()和connection.exec(),依然是无法启用事务的。
3.sdr提供SessionCallback接口用于同线程的多操作执行。(同一个连接)
非连接池环境下,事务操作;对于sdr而言,每次操作(例如,get,set)都有会从pool中获取connection;
因此在连接池环境下,使用事务需要注意。
public void saveNoPoolUser(final User user) { redisTemplate.watch("user:" + user.getId()); redisTemplate.multi(); ValueOperations<String, String> tvo = redisTemplate.opsForValue(); tvo.set("user:" + user.getId(), seriaziler.seriazileAsString(user)); redisTemplate.exec(); }
在连接池环境中,需要借助sessionCallback来绑定connection
public void savePoolUser(final User user) { SessionCallback<User> sessionCallback = new SessionCallback<User>() { @Override public User execute(RedisOperations operations) throws DataAccessException { operations.multi(); String key = "user:" + user.getId(); ValueOperations<String, String> oper = operations.opsForValue(); oper.set(key,seriaziler.seriazileAsString(user)); operations.exec(); return user; } }; redisTemplate.execute(sessionCallback); }
SpringDataRedisTransactional.java
package com.redis; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; public class SpringDataRedisTransactional { public static void main(String[] args) throws InterruptedException { ApplicationContext applicationContext = new ClassPathXmlApplicationContext("classpath:/applicationContext.xml"); RedisClientTest redisClientTest = (RedisClientTest) applicationContext.getBean("redisClientTest"); System.out.println("redisClientTest == " + redisClientTest); User user1 = new User(); user1.setId(33); user1.setName("obama31 55"); redisClientTest.savePoolUser(user1); System.out.println("insertUser"); User user2 = redisClientTest.getUser(33); System.out.println("user2 == " + user2.toString()); } }
RedisClientTest.java
package com.redis; import javax.annotation.Resource; import org.springframework.dao.DataAccessException; import org.springframework.data.redis.core.RedisOperations; import org.springframework.data.redis.core.RedisTemplate; import org.springframework.data.redis.core.SessionCallback; import org.springframework.data.redis.core.ValueOperations; import org.springframework.stereotype.Service; import org.springframework.transaction.annotation.Transactional; @Service("redisClientTest") public class RedisClientTest { @Resource(name = "jsonRedisSeriaziler") private JsonRedisSeriaziler seriaziler; @Resource(name = "redisTemplate") private RedisTemplate redisTemplate; public void insertUser(User user) { ValueOperations<String, String> operations = redisTemplate.opsForValue(); operations.set("user:" + user.getId(), seriaziler.seriazileAsString(user)); } public User getUser(long id) { ValueOperations<String, String> operations = redisTemplate.opsForValue(); String json = operations.get("user:" + id); System.out.println("json ==" + json); return seriaziler.deserializeAsObject(json, User.class); } public void savePoolUser(final User user) { SessionCallback<User> sessionCallback = new SessionCallback<User>() { @Override public User execute(RedisOperations operations) throws DataAccessException { operations.multi(); String key = "user:" + user.getId(); ValueOperations<String, String> oper = operations.opsForValue(); oper.set(key, seriaziler.seriazileAsString(user)); operations.exec(); return user; } }; redisTemplate.execute(sessionCallback); } public void saveNoPoolUser(final User user) { redisTemplate.watch("user:" + user.getId()); redisTemplate.multi(); ValueOperations<String, String> tvo = redisTemplate.opsForValue(); tvo.set("user:" + user.getId(), seriaziler.seriazileAsString(user)); redisTemplate.exec(); } }
Pipeline
1.就是先将命令缓存起来,到时一次打包发送到redis服务器进行处理
2.通过pipeline方式当有大批量的操作时候,我们可以节省很多原来浪费在网络延迟的时间,需要注意到是用pipeline方式打包命令发送,
redis必须在处理完所有命令前先缓存起所有命令的处理结果。打包的命令越多,缓存消耗内存也越多。所以并不是打包的命令越多越好。
如果存储的是数字(当然值的序列化方式要先用StringRedisSerializer否则不能用increment)
package com.redis; import java.io.Serializable; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import org.springframework.data.redis.core.RedisTemplate; import org.springframework.data.redis.core.ValueOperations; public class SpringDataRedisTestLong { public static void main(String[] args) throws InterruptedException { ApplicationContext applicationContext = new ClassPathXmlApplicationContext("classpath:/applicationContext.xml"); RedisTemplate redisTemplate = (RedisTemplate) applicationContext.getBean("redisTemplate"); System.out.println("redisTemplate == " + redisTemplate); ValueOperations<String, Serializable> valueOper = redisTemplate.opsForValue(); long i = 10245; valueOper.set("u:u53", String.valueOf(i)); System.out.println("redisTemplate == 100"); valueOper.increment("u:u53", 3L);//负数实现减操作 System.out.println("redisTemplate == 100"); String User = (String) valueOper.get("u:u53"); System.out.println("User == " + User); long j =Long.parseLong(User); System.out.println("j == " + j); } }
参考原文: http://www.cnblogs.com/luochengqiuse/p/4640932.html[/b]
参考原文: http://shift-alt-ctrl.iteye.com/blog/1887370
参考原文: http://shift-alt-ctrl.iteye.com/blog/1886831
参考原文(性能对比): http://blog.csdn.net/u010739551/article/details/48165063
所用到的jar包如下: