org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer.java Source code

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Here is the source code for org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer.java

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/*
 * Copyright 2015 the original author or authors.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.springframework.data.redis.serializer;

import org.springframework.util.Assert;
import org.springframework.util.StringUtils;

import com.fasterxml.jackson.annotation.JsonTypeInfo;
import com.fasterxml.jackson.annotation.JsonTypeInfo.As;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.ObjectMapper.DefaultTyping;
import com.fasterxml.jackson.databind.ser.SerializerFactory;

/**
 * @author Christoph Strobl
 * @since 1.6
 */
public class GenericJackson2JsonRedisSerializer implements RedisSerializer<Object> {

    private final ObjectMapper mapper;

    /**
     * Creates {@link GenericJackson2JsonRedisSerializer} and configures {@link ObjectMapper} for default typing.
     */
    public GenericJackson2JsonRedisSerializer() {
        this((String) null);
    }

    /**
     * Setting a custom-configured {@link ObjectMapper} is one way to take further control of the JSON serialization
     * process. For example, an extended {@link SerializerFactory} can be configured that provides custom serializers for
     * specific types.
     *
     * @param mapper
     *            must not be {@literal null}.
     */
    public GenericJackson2JsonRedisSerializer(ObjectMapper mapper) {

        Assert.notNull(mapper, "ObjectMapper must not be null!");
        this.mapper = mapper;
    }

    /**
     * Creates {@link GenericJackson2JsonRedisSerializer} and configures {@link ObjectMapper} for default typing using the
     * given {@literal name}. In case of an {@literal empty} or {@literal null} String the default {@link JsonTypeInfo.Id#CLASS} will be used.
     *
     * @param classPropertyTypeName
     *            Name of the JSON property holding type information. Can be {@literal null}.
     */
    public GenericJackson2JsonRedisSerializer(String classPropertyTypeName) {

        this(new ObjectMapper());

        if (StringUtils.hasText(classPropertyTypeName)) {
            mapper.enableDefaultTypingAsProperty(DefaultTyping.NON_FINAL, classPropertyTypeName);
        } else {
            mapper.enableDefaultTyping(DefaultTyping.NON_FINAL, As.PROPERTY);
        }
        mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
    }

    /*
     * (non-Javadoc)
     * @see org.springframework.data.redis.serializer.RedisSerializer#deserialize(byte[])
     */
    @Override
    public Object deserialize(byte[] source) throws SerializationException {
        return deserialize(source, Object.class);
    }

    /**
     * @param source
     *            can be {@literal null}.
     * @param type
     *            must not be {@literal null}.
     * @return {@literal null} for empty source.
     * @throws SerializationException
     */
    public <T> T deserialize(byte[] source, Class<T> type) throws SerializationException {

        Assert.notNull(type,
                "Deserialization type must not be null! Pleaes provide Object.class to make use of Jackson2 default typing.");

        if (SerializationUtils.isEmpty(source)) {
            return null;
        }

        try {
            return mapper.readValue(source, type);
        } catch (final Exception ex) {
            throw new SerializationException("Could not read JSON: " + ex.getMessage(), ex);
        }
    }

    /*
     * (non-Javadoc)
     * @see org.springframework.data.redis.serializer.RedisSerializer#serialize(java.lang.Object)
     */
    @Override
    public byte[] serialize(Object source) throws SerializationException {

        if (source == null) {
            return SerializationUtils.EMPTY_ARRAY;
        }

        try {
            return mapper.writeValueAsBytes(source);
        } catch (final JsonProcessingException e) {
            throw new SerializationException("Could not write JSON: " + e.getMessage(), e);
        }
    }
}