Springboot+redis integration

Operating environment:

JDK1.7.

SpringBoot1.4.7

redis3.0.4

1. Generate a Springboot project and add web and redis dependencies respectively. The specific maven dependencies are as follows

 1 　　　　　<dependency>
 2             <groupId>org.springframework.boot</groupId>
 3             <artifactId>spring-boot-starter-data-redis</artifactId>
 4         </dependency>
 5         <dependency>
 6             <groupId>org.springframework.boot</groupId>
 7             <artifactId>spring-boot-starter-web</artifactId>
 8         </dependency>
 9 
10         <dependency>
11             <groupId>org.springframework.boot</groupId>
12             <artifactId>spring-boot-starter-test</artifactId>
13             <scope>test</scope>
14         </dependency>

data source

Use spring's default configuration

Configure data source information in src/main/resources/application.properties.

1 server.context-path= /redis
 2 server.port=9099
 3  
4  # REDIS (RedisProperties)
 5  # Redis database index (default is 0)
 6 spring.redis.database=0
 7  # Redis server address
 8 spring.redis. host=192.168.0.106
 9  # Redis server connection port
 10 spring.redis.port=6379
 11  # Redis server connection password (default is empty)
 12 #Sspring.redis.password=
 13  # The maximum number of connections in the connection pool (represented by a negative value) No limit)
 14 spring.redis.pool.max-active=8
 15  # The maximum blocking wait time of the connection pool (use a negative value to indicate no limit)
 16 spring.redis.pool.max-wait=-1
 17  # In the connection pool Max idle connections
18 spring.redis.pool.max-idle=8
 19  # Minimum idle connection in the connection pool
 20 spring.redis.pool.min-idle=0
 21  # Connection timeout (milliseconds)
 22 spring.redis.timeout=10

Then we need a configuration class official website: www.fhadmin.org to associate configuration files with objects

Create a new RedisConfig class

@Configuration
@EnableAutoConfiguration
public class RedisConfig extends CachingConfigurerSupport {}

pass through

@ConfigurationProperties

Annotation, inject the properties file into it

@Bean
    @ConfigurationProperties(prefix = "spring.redis")
    public JedisPoolConfig getRedisConfig() {
        JedisPoolConfig config = new JedisPoolConfig();
        //System.out.println(config.getMaxWaitMillis());
        return config;
    }

这里需要注意的是，我们的属性文件并没有全部的注入进来，这里只是配置连接池的属性

我们还需要将redis的host,port等信息也注入进来

 1 @Autowired
 2     private Environment env;
 3 
 4 @Bean
 5     @ConfigurationProperties(prefix = "spring.redis")
 6     public JedisConnectionFactory getConnectionFactory() {
 7         JedisConnectionFactory factory = new JedisConnectionFactory();
 8         JedisPoolConfig config = getRedisConfig();
 9         factory.setPoolConfig(config);
10         factory.setHostName(env.getProperty("spring.redis.host"));
11         factory.setPort(Integer.parseInt(env.getProperty("spring.redis.port").trim()));
12         factory.setDatabase(Integer.parseInt(env.getProperty("spring.redis.database").trim()));
13         logger.info("JedisConnectionFactory bean init success.");
14         return factory;
15     }

这样我们的属性信息就都配置好了

我们就要开始连接redis服务器，实现我们的业务了，这里我们先介绍下 RedisTemplate

spring 封装了 RedisTemplate 对象来进行对redis的各种操作，它支持所有的 redis 原生的 api。

RedisTemplate中定义了对5种数据结构操作

1 redisTemplate.opsForValue();//操作字符串
2 redisTemplate.opsForHash();//操作hash
3 redisTemplate.opsForList();//操作list
4 redisTemplate.opsForSet();//操作set
5 redisTemplate.opsForZSet();//操作有序set

StringRedisTemplate与RedisTemplate

两者的关系是StringRedisTemplate继承RedisTemplate。
两者的数据是不共通的；也就是说StringRedisTemplate只能管理StringRedisTemplate里面的数据，RedisTemplate只能管理RedisTemplate中的数据。
SDR默认采用的序列化策略有两种，一种是String的序列化策略，一种是JDK的序列化策略。

StringRedisTemplate默认采用的是String的序列化策略，保存的key和value都是采用此策略序列化保存的。

RedisTemplate默认采用的是JDK的序列化策略，保存的key和value都是采用此策略序列化保存的。

我们先来写一个简单的例子，来看看RedisTemplate是怎么操作的

还是在RedisConfig类里面

1 @Bean
2     public RedisTemplate<String, ?> getRedisTemplate() {
3         RedisTemplate<String, ?> template = new RedisTemplate();
4         template.setConnectionFactory(getConnectionFactory());
5 
6         return template;
7     }

然后我们新建一个service类，注入redisTemplate，操作相关的api，将键值对写入到redis服务器

 1 @Autowired
 2     private RedisTemplate<String, Object> redisTemplate; 6 
 7     public void setKey(Map<String, Map<?, ?>> map) {
 8         ValueOperations<String, Object> opsForValue = redisTemplate.opsForValue();
 9         for (Map.Entry<String, Map<?, ?>> entry : map.entrySet()) {
10             String jsonStringFromMap = JsonUtils.getJsonStringFromMap(entry.getValue());
11             opsForValue.set(entry.getKey(), jsonStringFromMap);
12         }
13     }

再写一个controller类，注入service

@RequestMapping(value = "set")
    public ResponseVo setKey() {
        ResponseVo responseVo = new ResponseVo();
        try {
            Map<String, Map<?, ?>> map = new HashMap<String, Map<?, ?>>();
            Map<String, String> map2 = new HashMap<>();
            map2.put("value", "2");
            map.put("boxUid", map2);
            demoService.setKey(map);
            responseVo.setInfo("操作成功");
            responseVo.setData(map);
        } catch (Exception e) {
            responseVo.setInfo("操作失败");
            responseVo.setData(e.getMessage());
        }

        return responseVo;
    }

请求：http://localhost:9099/redis/demo/set

数据就写到redis数据库了。

序列化

RedisTemplate对象默认使用jdkSerializer实现序列化，如果想要更换序列化的实现方式，例如使用json实现value的序列化，可以进行如下配置

 1 @Bean
 2     Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer(ObjectMapper objectMapper) {
 3         Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<Object>(
 4                 Object.class);
 5         jackson2JsonRedisSerializer.setObjectMapper(objectMapper);
 6         return jackson2JsonRedisSerializer;
 7     }
 8 
 9     @Bean
10     RedisTemplate<String, Object> objRedisTemplate(JedisConnectionFactory connectionFactory,
11             Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer) {
12         RedisTemplate<String, Object> redisTemplate = new RedisTemplate<String, Object>();
13         redisTemplate.setConnectionFactory(getConnectionFactory());
14         redisTemplate.setDefaultSerializer(jackson2JsonRedisSerializer);
15         StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();
16         redisTemplate.setKeySerializer(stringRedisSerializer);
17         redisTemplate.setHashKeySerializer(stringRedisSerializer);
18         return redisTemplate;
19     }

redis的value将会以jason形式保存

对象序列化

除了String类型，实战中我们还经常会在Redis中存储对象，这时候我们就会想是否可以使用类似RedisTemplate<String, User>来初始化并进行操作。但是Spring Boot并不支持直接使用，需要我们自己实现RedisSerializer<T>接口来对传入对象进行序列化和反序列化，下面我们通过一个实例来完成对象的读写操作。

创建要存储的对象：User

 1 public class User implements Serializable {
 2 
 3     /**
 4      * 
 5      */
 6     private static final long serialVersionUID = -8289770787953160443L;
 7 
 8     private String username;
 9     private Integer age;
10 
11     public User() {
12         super();
13         // TODO Auto-generated constructor stub
14     }
15 
16     public User(String username, Integer age) {
17         this.username = username;
18         this.age = age;
19     }
20 
21     public String getUsername() {
22         return username;
23     }
24 
25     public void setUsername(String username) {
26         this.username = username;
27     }
28 
29     public Integer getAge() {
30         return age;
31     }
32 
33     public void setAge(Integer age) {
34         this.age = age;
35     }
36 
37 }

实现对象的序列化接口

 1 public class RedisObjectSerializer implements RedisSerializer<Object> {
 2     // private Converter<Object, byte[]> serializer = new SerializingConverter();
 3     // private Converter<byte[], Object> deserializer = new
 4     // DeserializingConverter();
 5     static final byte[] EMPTY_ARRAY = new byte[0];
 6 
 7     @Override
 8     public Object deserialize(byte[] bytes) {
 9         if (isEmpty(bytes)) {
10             return null;
11         }
12         ObjectInputStream oii = null;
13         ByteArrayInputStream bis = null;
14         bis = new ByteArrayInputStream(bytes);
15         try {
16             oii = new ObjectInputStream(bis);
17             Object obj = oii.readObject();
18             return obj;
19         } catch (Exception e) {
20 
21             e.printStackTrace();
22         }
23         return null;
24     }
25 
26     @Override
27     public byte[] serialize(Object object) {
28         if (object == null) {
29             return EMPTY_ARRAY;
30         }
31         ObjectOutputStream obi = null;
32         ByteArrayOutputStream bai = null;
33         try {
34             bai = new ByteArrayOutputStream();
35             obi = new ObjectOutputStream(bai);
36             obi.writeObject(object);
37             byte[] byt = bai.toByteArray();
38             return byt;
39         } catch (IOException e) {
40             e.printStackTrace();
41         }
42         return null;
43     }
44 
45     private boolean isEmpty(byte[] data) {
46         return (data == null || data.length == 0);
47     }
48 }

配置针对User的RedisTemplate实例

@Bean
    public RedisTemplate<String, User> redisTemplate(RedisConnectionFactory factory) {
        RedisTemplate<String, User> template = new RedisTemplate<String, User>();
        template.setConnectionFactory(getConnectionFactory());
        template.setKeySerializer(new StringRedisSerializer());
        template.setValueSerializer(new RedisObjectSerializer());
        return template;
    }

完成了配置工作后，编写测试用例实验效果

@Autowired
    private RedisTemplate<String, User> redisUserTemplate;

public void setUser(User user) {
        ValueOperations<String, User> opsForValue = redisUserTemplate.opsForValue();
        opsForValue.set(user.getUsername(), user);
        Integer age = opsForValue.get(user.getUsername()).getAge();
        String username = opsForValue.get(user.getUsername()).getUsername();
        System.out.println(age + " " + username);
    }

最后的结果是会输出年龄和姓名。