RedisSerializer之JdkSerializationRedisSerializer分析

redis在緩存POJO的時候須要將POJO序列化爲byte數組進行存儲，spring-data-redis實現了類JdkSerializationRedisSerializer對POJO進行序列化。類圖結構如上，主要流程以下：

1.JdkSerializationRedisSerializer類實現接口RedisSerializer類中
byte[] serialize(T t)和T deserialize(byte[] bytes)接口。

2.經過定義SerializingConverter和DeserializingConverter對象，對POJO進行序列化和反序列化。

public JdkSerializationRedisSerializer() {
        this(new SerializingConverter(), new DeserializingConverter());
    }

3.對於SerializingConverter，經過定義DefaultSerializer對象並調用serialize(Object object, OutputStream outputStream)方法，對POJO進行序列化操做。

public SerializingConverter() {
            this.serializer = new DefaultSerializer();
        }

    @Override
    public byte[] convert(Object source) {
        ByteArrayOutputStream byteStream = new ByteArrayOutputStream(1024);
        try  {
            this.serializer.serialize(source, byteStream);
            return byteStream.toByteArray();
        }
        catch (Throwable ex) {
            throw new SerializationFailedException("Failed to serialize object using " +
                    this.serializer.getClass().getSimpleName(), ex);
        }
    }
    
    public class DefaultSerializer implements Serializer<Object> {
    @Override
    public void serialize(Object object, OutputStream outputStream) throws IOException {
        if (!(object instanceof Serializable)) {
            throw new IllegalArgumentException(getClass().getSimpleName() + " requires a Serializable payload " +
                    "but received an object of type [" + object.getClass().getName() + "]");
        }
        ObjectOutputStream objectOutputStream = new ObjectOutputStream(outputStream);
        objectOutputStream.writeObject(object);
        objectOutputStream.flush();
    }

}

4.對於DeserializingConverter，經過定義DefaultDeserializer對象並調用deserialize(InputStream inputStream)方法對POJO進行反序列化。

public DeserializingConverter() {
        this.deserializer = new DefaultDeserializer();
    }

@Override
    public Object convert(byte[] source) {
        ByteArrayInputStream byteStream = new ByteArrayInputStream(source);
        try {
            return this.deserializer.deserialize(byteStream);
        }
        catch (Throwable ex) {
            throw new SerializationFailedException("Failed to deserialize payload. " +
                    "Is the byte array a result of corresponding serialization for " +
                    this.deserializer.getClass().getSimpleName() + "?", ex);
        }
    }

public class DefaultDeserializer implements Deserializer<Object> {

    private final ClassLoader classLoader;

    @Override
    @SuppressWarnings("resource")
    public Object deserialize(InputStream inputStream) throws IOException {
        ObjectInputStream objectInputStream = new ConfigurableObjectInputStream(inputStream, this.classLoader);
        try {
            return objectInputStream.readObject();
        }
        catch (ClassNotFoundException ex) {
            throw new NestedIOException("Failed to deserialize object type", ex);
        }
    }

}

5.底層仍是經過調用JDK的IO操做ObjectInputStream和ObjectOutputStream類實現POJO的序列化和反序列化。