问题
最近在整一个spring data redis，网上有一本《Spring Data》的电子书（我一个朋友正在翻译，应该今年会有中文版出来，人邮的），下载来看了一下，其中第8章讲到了Spring data对redis的支持。 redis虽然提供了对list set hash等数据类型的支持，但是没有提供对POJO对象的支持，底层都是把对象序列化后再以字符串的方式存储的。因此，Spring data提供了若干个Serializer，主要包括：JacksonJsonRedisSerializer
JdkSerializationRedisSerializer
OxmSerializer
Java代码 
package com.oreilly.springdata.redis;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlRootElement;
import java.io.Serializable;
/**
* @author : stamen
* @date: 13-7-16
*/
@XmlAccessorType(XmlAccessType.FIELD)
@XmlRootElement(name = "user")
public class User implements Serializable {
@XmlAttribute
private String userName;
@XmlAttribute
private int age;
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}
由于后面，我们需要使用OXM及Jackson将进行对象序列，为了控制对象的序列化，因此打上了JSR 175注解。 更改ApplicationConfig ApplicationConfig是Spring容器的配置类，要根据你的环境进行更改，我的更改为：
Java代码
package com.oreilly.springdata.redis;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.OxmSerializer;
import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.data.redis.serializer.SerializationException;
import org.springframework.oxm.jaxb.Jaxb2Marshaller;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.Marshaller;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
/**
* @author Jon Brisbin
*/
@Configuration
public abstract class ApplicationConfig {
@Bean
public RedisConnectionFactory redisConnectionFactory() {
JedisConnectionFactory cf = new JedisConnectionFactory();
cf.setHostName("10.188.182.140");
cf.setPort(6379);
cf.setPassword("superman");
cf.afterPropertiesSet();
return cf;
}
@Bean
public RedisTemplate redisTemplate() {
RedisTemplate rt = new RedisTemplate();
rt.setConnectionFactory(redisConnectionFactory());
return rt;
}
private static Map<Class, JAXBContext> jaxbContextHashMap = new ConcurrentHashMap<Class, JAXBContext>();
@Bean
public OxmSerializer oxmSerializer() throws Throwable{
Jaxb2Marshaller jaxb2Marshaller = new Jaxb2Marshaller();
Map<String,Object> properties = new HashMap<String, Object>();//创建映射，用于设置Marshaller属性
properties.put(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE); //放置xml自动缩进属性
properties.put(Marshaller.JAXB_ENCODING,"utf-8"); //放置xml自动缩进属性
jaxb2Marshaller.setClassesToBeBound(User.class);//映射的xml类放入JAXB环境中
jaxb2Marshaller.setMarshallerProperties(properties);//设置Marshaller属性
return new OxmSerializer(jaxb2Marshaller,jaxb2Marshaller);
}
public static enum StringSerializer implements RedisSerializer<String> {
INSTANCE;
@Override
public byte[] serialize(String s) throws SerializationException {
return (null != s ? s.getBytes() : new byte[0]);
}
@Override
public String deserialize(byte[] bytes) throws SerializationException {
if (bytes.length > 0) {
return new String(bytes);
} else {
return null;
}
}
}
public static enum LongSerializer implements RedisSerializer<Long> {
INSTANCE;
@Override
public byte[] serialize(Long aLong) throws SerializationException {
if (null != aLong) {
return aLong.toString().getBytes();
} else {
return new byte[0];
}
}
@Override
public Long deserialize(byte[] bytes) throws SerializationException {
if (bytes.length > 0) {
return Long.parseLong(new String(bytes));
} else {
return null;
}
}
}
public static enum IntSerializer implements RedisSerializer<Integer> {
INSTANCE;
@Override
public byte[] serialize(Integer i) throws SerializationException {
if (null != i) {
return i.toString().getBytes();
} else {
return new byte[0];
}
}
@Override
public Integer deserialize(byte[] bytes) throws SerializationException {
if (bytes.length > 0) {
return Integer.parseInt(new String(bytes));
} else {
return null;
}
}
}
}
Java代码
@Test
public void testJdkSerialiable() {
RedisTemplate<String, Serializable> redis = new RedisTemplate<String, Serializable>();
redis.setConnectionFactory(connectionFactory);
redis.setKeySerializer(ApplicationConfig.StringSerializer.INSTANCE);
redis.setValueSerializer(new JdkSerializationRedisSerializer());
redis.afterPropertiesSet();
ValueOperations<String, Serializable> ops = redis.opsForValue();
User user1 = new User();
user1.setUserName("user1");
user1.setAge(20);
String key1 = "users/user1";
User user11 = null;
long begin = System.currentTimeMillis();
for (int i = 0; i < 100; i++) {
ops.set(key1,user1);
user11 = (User)ops.get(key1);
}
long time = System.currentTimeMillis() - begin;
System.out.println("jdk time:"+time);
assertThat(user11.getUserName(),is("user1"));
}
引用
redis 127.0.0.1:6379> get users/user1 "\xac\xed\x00\x05sr\x00!com.oreilly.springdata.redis.User\xb1\x1c \n\xcd\xed%\xd8\x02\x00\x02I\x00\x03ageL\x00\buserNamet\x00\x12Ljava/lang/String;xp\x00\x00\x00\x14t\x00\x05user1" 通过strlen查看对应的字符长度：引用
redis 127.0.0.1:6379> strlen users/user1 (integer) 104 上面的代码共进行了100次的存储和获取，其所花时间如下（毫秒）：引用
jdk time:266
使用JacksonJsonRedisSerializer序列化Java代码
@Test
public void testJacksonSerialiable() {
RedisTemplate<String, Object> redis = new RedisTemplate<String, Object>();
redis.setConnectionFactory(connectionFactory);
redis.setKeySerializer(ApplicationConfig.StringSerializer.INSTANCE);
redis.setValueSerializer(new JacksonJsonRedisSerializer<User>(User.class));
redis.afterPropertiesSet();
ValueOperations<String, Object> ops = redis.opsForValue();
User user1 = new User();
user1.setUserName("user1");
user1.setAge(20);
User user11 = null;
String key1 = "json/user1";
long begin = System.currentTimeMillis();
for (int i = 0; i < 100; i++) {
ops.set(key1,user1);
user11 = (User)ops.get(key1);
}
long time = System.currentTimeMillis() - begin;
System.out.println("json time:"+time);
assertThat(user11.getUserName(),is("user1"));
}
引用
redis 127.0.0.1:6379> get json/user1 "{\"userName\":\"user1\",\"age\":20}" redis 127.0.0.1:6379> strlen json/user1 (integer) 29 执行花费时间为：引用
json time:224 使用OxmSerialiable序列化Java代码
@Test
public void testOxmSerialiable() throws Throwable{
RedisTemplate<String, Object> redis = new RedisTemplate<String, Object>();
redis.setConnectionFactory(connectionFactory);
redis.setKeySerializer(ApplicationConfig.StringSerializer.INSTANCE);
redis.setValueSerializer(oxmSerializer);
redis.afterPropertiesSet();
ValueOperations<String, Object> ops = redis.opsForValue();
User user1 = new User();
user1.setUserName("user1");
user1.setAge(20);
User user11 = null;
String key1 = "oxm/user1";
long begin = System.currentTimeMillis();
for (int i = 0; i < 100; i++) {
ops.set(key1,user1);
user11 = (User)ops.get(key1);
}
long time = System.currentTimeMillis() - begin;
System.out.println("oxm time:"+time);
assertThat(user11.getUserName(),is("user1"));
}
引用
redis 127.0.0.1:6379> get oxm/user1 "<?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"yes\"?>\n<user age=\"20\" userName=\"user1\"/>\n" redis 127.0.0.1:6379> strlen oxm/user1 (integer) 90 执行花费时间为：引用
oxm time:335 小结 从执行时间上来看，JdkSerializationRedisSerializer是最高效的（毕竟是JDK原生的），但是是序列化的结果字符串是最长的。JSON由于其数据格式的紧凑性，序列化的长度是最小的，时间比前者要多一些。而OxmSerialiabler在时间上看是最长的（当时和使用具体的Marshaller有关）。所以个人的选择是倾向使用JacksonJsonRedisSerializer作为POJO的序列器。(11.1 KB)