Spring Data Redis - RedisTemplate 随说

public class RedisTemplate<K, V> extends RedisAccessor implements RedisOperations<K, V>, BeanClassLoaderAware {

	private boolean enableTransactionSupport = false;
	private boolean exposeConnection = false;
	private boolean initialized = false;
	private boolean enableDefaultSerializer = true;
	private @Nullable RedisSerializer<?> defaultSerializer;
	private @Nullable ClassLoader classLoader;

	@SuppressWarnings("rawtypes") private @Nullable RedisSerializer keySerializer = null;
	@SuppressWarnings("rawtypes") private @Nullable RedisSerializer valueSerializer = null;
	@SuppressWarnings("rawtypes") private @Nullable RedisSerializer hashKeySerializer = null;
	@SuppressWarnings("rawtypes") private @Nullable RedisSerializer hashValueSerializer = null;
	private RedisSerializer<String> stringSerializer = new StringRedisSerializer();

	private @Nullable ScriptExecutor<K> scriptExecutor;

	// cache singleton objects (where possible)
	private @Nullable ValueOperations<K, V> valueOps;
	private @Nullable ListOperations<K, V> listOps;
	private @Nullable SetOperations<K, V> setOps;
	private @Nullable ZSetOperations<K, V> zSetOps;
	private @Nullable GeoOperations<K, V> geoOps;
	private @Nullable HyperLogLogOperations<K, V> hllOps;
}

opsForValue().set("key","value");
boundValueOps("key").set("value"); // 不要这样操作，会产生很多 bounded operator（绑定操作对象）

/**
 * Basic interface serialization and deserialization of Objects to byte arrays (binary data). It is recommended that
 * implementations are designed to handle null objects/empty arrays on serialization and deserialization side. Note that
 * Redis does not accept null keys or values but can return null replies (for non existing keys).
 *
 * @author Mark Pollack
 * @author Costin Leau
 * @author Christoph Strobl
 */
public interface RedisSerializer<T> {

	/**
	 * Serialize the given object to binary data.
	 *
	 * @param t object to serialize. Can be {@literal null}.
	 * @return the equivalent binary data. Can be {@literal null}.
	 */
	@Nullable
	byte[] serialize(@Nullable T t) throws SerializationException;

	/**
	 * Deserialize an object from the given binary data.
	 *
	 * @param bytes object binary representation. Can be {@literal null}.
	 * @return the equivalent object instance. Can be {@literal null}.
	 */
	@Nullable
	T deserialize(@Nullable byte[] bytes) throws SerializationException;
}

public abstract class InMemoryStoreAdapter<T> implements InMemoryStore {
	private final static byte[] EMPTY_ARRAY = new byte[0];
    
    // ......其他无关紧要的东西
    
    protected final RedisTemplate<String, T> redisTemplate;
    
    // 所有的子类都使用同一个 KeySerializer 实例
    private final static RedisSerializer<String> keySerializer = new StringRedisSerializer();

    // 所有的子类都使用同一个 ObjectMapper 实例
    private final static ObjectMapper objectMapper = new ObjectMapper();
    
    // 构造器
    protected InMemoryStoreAdapter(RedisConnectionFactory redisConnectionFactory, String domain) {
        // 这里新建一个 RedisTemplate 给自己用
        this.redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(redisConnectionFactory);

        // 获取自己的泛型参数类型信息，自己存储。
        Type mainType = getClass().getGenericSuperclass();
        ParameterizedType parameterizedType = (ParameterizedType) mainType;
        Class<T> mainTypeClass = (Class<T>) parameterizedType.getActualTypeArguments()[0];

        // 每个子类的 redisTemplate 都有自己的 ValueSerializer ，我直接把它写成匿名类了。
        RedisSerializer<T> valueSerializer = new RedisSerializer<T>() {
            // ObjectReader 其实也是个上下文存储对象，里面包含了类型信息，
            // 用的 ObjectMapper 还是原来的那个
            private final ObjectReader objectReader = objectMapper.readerFor(mainTypeClass);
            private final ObjectWriter objectWriter = objectMapper.writer();

            @Override
            public byte[] serialize(T t) throws SerializationException {
                try {
                    return t == null ? EMPTY_ARRAY : objectWriter.writeValueAsBytes(t);
                } catch (JsonProcessingException e) {
                    throw new SerializationException("Could not write object to JSON: ", e);
                }
            }

            @Override
            public T deserialize(byte[] bytes) throws SerializationException {
                try {
                    return (bytes == null || bytes.length <= 0) ? null : objectReader.readValue(bytes);
                } catch (IOException e) {
                    throw new SerializationException("Could not read object from JSON: ", e);
                }
            }
        };

        // 设定各个序列化器
        redisTemplate.setDefaultSerializer(valueSerializer);

        redisTemplate.setKeySerializer(keySerializer);
        redisTemplate.setHashKeySerializer(keySerializer);

        redisTemplate.setValueSerializer(valueSerializer);

        // 记得调用 afterPropertiesSet()
        redisTemplate.afterPropertiesSet();

        // ......其他代码
    }
}