Redis序列化操作-编程知识

Redis序列化操作

1.protostuff 的 Maven 依赖

2.定义实体类

3.序列化工具类 ProtostuffSerializer 提供了序列化和反序列化方法

4.测试

利用 Jedis 提供的字节数组参数方法，如：

public String set(String key, String value)

public String set(byte[] key, byte[] value)

public byte[] get(byte[] key)

public String get(String key)

拥用这些 API 的支持，就可以将 Java 对象序列化为二进制，当应用需要获取 Java 对象时，使用 public byte[] get(byte[] key) 函数将字节数组取出，然后反序列化为 Java 对象即可。和很多 NoSQL 数据库（例如Memchache、Ehcache）的客户端不同，Jedis 本身没有提供序列化的工具，也就是说开发者需要自己引入序列化的工具。序列化的工具有很多，例如 XML、Json、谷歌的 Protobuf 、Facebook 的 Thrift 等等，对于序列化工具的选择开发者可以根据自身的需求决定，下面以 protostuff (Protobuf 的 Java 客户端)为例子进行说明。

1.protostuff 的 Maven 依赖

    <properties><protostuff.version>1.0.11</protostuff.version></properties><dependencies>//redis客户端<dependency><groupId>redis.clients</groupId><artifactId>jedis</artifactId><version>2.8.2</version></dependency>//protostuff 客户端<dependency><groupId>com.dyuproject.protostuff</groupId><artifactId>protostuff-runtime</artifactId><version>${protostuff.version}</version></dependency><dependency><groupId>com.dyuproject.protostuff</groupId><artifactId>protostuff-core</artifactId><version>${protostuff.version}</version></dependency></dependencies>

2.定义实体类

package org.example.Entity;import java.io.Serializable;
import java.util.Date;public class Club implements Serializable {private int id;     //idprivate String name;//名称private String info;//描述private Date createDate;//创建日期private int rank;public Club(int id, String name, String info, Date createDate, int rank) {this.id = id;this.name = name;this.info = info;this.createDate = createDate;this.rank = rank;}public int getId() {return id;}public void setId(int id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getInfo() {return info;}public void setInfo(String info) {this.info = info;}public Date getCreateDate() {return createDate;}public void setCreateDate(Date createDate) {this.createDate = createDate;}public int getRank() {return rank;}public void setRank(int rank) {this.rank = rank;}//测试使用@Overridepublic String toString() {return "Club{" +"id=" + id +", name='" + name + '\'' +", info='" + info + '\'' +", createDate=" + createDate +", rank=" + rank +'}';}
}

3.序列化工具类 ProtostuffSerializer 提供了序列化和反序列化方法

package org.example.until;import com.dyuproject.protostuff.LinkedBuffer;
import com.dyuproject.protostuff.ProtostuffIOUtil;
import com.dyuproject.protostuff.Schema;
import com.dyuproject.protostuff.runtime.RuntimeSchema;
import org.example.Entity.Club;
//序列化工具类
public class ProtostuffSerializer {// 通过反射机制创建了 Club 类型的模式（schema）private Schema<Club> schema = RuntimeSchema.createFrom(Club.class);//序列化public byte[] serialize(Club club){//初始化序列化缓冲LinkedBuffer buffer = LinkedBuffer.allocate(LinkedBuffer.DEFAULT_BUFFER_SIZE);try {//序列化成字节数组return serializeInternal(club,schema,buffer);}catch (Exception e){throw new IllegalStateException(e.getMessage(),e);}finally {buffer.clear();}}//反序列化public Club deserialize(byte[] bytes){try {//拿到反序列化对象Club club = deserializeInternal(bytes,schema.newMessage(),schema);if (club != null){return club;}}catch (Exception e){throw new IllegalStateException(e.getMessage(),e);}return null;}//返回序列化数组private <T> byte[] serializeInternal(final T source,final Schema<T> schema,LinkedBuffer buffer) {return ProtostuffIOUtil.toByteArray(source,schema,buffer);}//将字节数组反序列化操作private <T> T deserializeInternal(byte[] bytes, T result, Schema<T> schema) {ProtostuffIOUtil.mergeFrom(bytes,result,schema);return result;}
}

4.测试

package org.example;import org.example.Entity.Club;
import org.example.until.ProtostuffSerializer;
import redis.clients.jedis.Jedis;import java.util.Date;// 按两次 Shift 打开“随处搜索”对话框并输入 `show whitespaces`，
// 然后按 Enter 键。现在，您可以在代码中看到空格字符。
public class Main {public static void main(String[] args) {//生成序列化工具类ProtostuffSerializer protostuffSerializer = new ProtostuffSerializer();Jedis jedis = JedusUtils.getJedis();String key = "club:1";//定义实体对象Club club = new Club(1,"AC","米兰",new Date(),1);System.out.println("序列化："+club);//序列化byte[] clubBytes = protostuffSerializer.serialize(club);jedis.set(key.getBytes(),clubBytes);//反序列化byte[] resultBytes = jedis.get(key.getBytes());//反序列化 1,"AC","米兰",new Date(),1Club resultClub = protostuffSerializer.deserialize(resultBytes);System.out.println("反序列化： "+resultClub);}
}

运行结果如图：