org.springframework.jms.support.converter.MessagingMessageConverter.java Source code

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Here is the source code for org.springframework.jms.support.converter.MessagingMessageConverter.java

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/*
 * Copyright 2002-2018 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
 *
 *      https://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.jms.support.converter;

import java.util.Map;
import javax.jms.JMSException;
import javax.jms.Session;

import org.springframework.beans.factory.InitializingBean;
import org.springframework.jms.support.JmsHeaderMapper;
import org.springframework.jms.support.SimpleJmsHeaderMapper;
import org.springframework.lang.Nullable;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageHeaders;
import org.springframework.messaging.core.AbstractMessagingTemplate;
import org.springframework.messaging.support.MessageBuilder;
import org.springframework.util.Assert;

/**
 * Convert a {@link Message} from the messaging abstraction to and from a
 * {@link javax.jms.Message} using an underlying {@link MessageConverter}
 * for the payload and a {@link org.springframework.jms.support.JmsHeaderMapper}
 * to map the JMS headers to and from standard message headers.
 *
 * @author Stephane Nicoll
 * @since 4.1
 */
public class MessagingMessageConverter implements MessageConverter, InitializingBean {

    private MessageConverter payloadConverter;

    private JmsHeaderMapper headerMapper;

    /**
     * Create an instance with a default payload converter.
     * @see org.springframework.jms.support.converter.SimpleMessageConverter
     * @see org.springframework.jms.support.SimpleJmsHeaderMapper
     */
    public MessagingMessageConverter() {
        this(new SimpleMessageConverter(), new SimpleJmsHeaderMapper());
    }

    /**
     * Create an instance with the specific payload converter.
     * @param payloadConverter the payload converter to use
     * @since 4.3.12
     */
    public MessagingMessageConverter(MessageConverter payloadConverter) {
        this(payloadConverter, new SimpleJmsHeaderMapper());
    }

    /**
     * Create an instance with the specified payload converter and
     * header mapper.
     */
    public MessagingMessageConverter(MessageConverter payloadConverter, JmsHeaderMapper headerMapper) {
        Assert.notNull(payloadConverter, "PayloadConverter must not be null");
        Assert.notNull(headerMapper, "HeaderMapper must not be null");
        this.payloadConverter = payloadConverter;
        this.headerMapper = headerMapper;
    }

    /**
     * Set the {@link MessageConverter} to use to convert the payload.
     */
    public void setPayloadConverter(MessageConverter payloadConverter) {
        this.payloadConverter = payloadConverter;
    }

    /**
     * Set the {@link JmsHeaderMapper} to use to map JMS headers to and from
     * standard message headers.
     */
    public void setHeaderMapper(JmsHeaderMapper headerMapper) {
        this.headerMapper = headerMapper;
    }

    @Override
    public void afterPropertiesSet() {
        Assert.notNull(this.payloadConverter, "Property 'payloadConverter' is required");
        Assert.notNull(this.headerMapper, "Property 'headerMapper' is required");
    }

    @Override
    public javax.jms.Message toMessage(Object object, Session session)
            throws JMSException, MessageConversionException {
        if (!(object instanceof Message)) {
            throw new IllegalArgumentException("Could not convert [" + object + "] - only ["
                    + Message.class.getName() + "] is handled by this converter");
        }
        Message<?> input = (Message<?>) object;
        MessageHeaders headers = input.getHeaders();
        Object conversionHint = headers.get(AbstractMessagingTemplate.CONVERSION_HINT_HEADER);
        javax.jms.Message reply = createMessageForPayload(input.getPayload(), session, conversionHint);
        this.headerMapper.fromHeaders(headers, reply);
        return reply;
    }

    @SuppressWarnings("unchecked")
    @Override
    public Object fromMessage(javax.jms.Message message) throws JMSException, MessageConversionException {
        Map<String, Object> mappedHeaders = extractHeaders(message);
        Object convertedObject = extractPayload(message);
        MessageBuilder<Object> builder = (convertedObject instanceof org.springframework.messaging.Message
                ? MessageBuilder.fromMessage((org.springframework.messaging.Message<Object>) convertedObject)
                : MessageBuilder.withPayload(convertedObject));
        return builder.copyHeadersIfAbsent(mappedHeaders).build();
    }

    /**
     * Extract the payload of the specified {@link javax.jms.Message}.
     */
    protected Object extractPayload(javax.jms.Message message) throws JMSException {
        return this.payloadConverter.fromMessage(message);
    }

    /**
     * Create a JMS message for the specified payload and conversionHint.
     * The conversion hint is an extra object passed to the {@link MessageConverter},
     * e.g. the associated {@code MethodParameter} (may be {@code null}}.
     * @since 4.3
     * @see MessageConverter#toMessage(Object, Session)
     */
    protected javax.jms.Message createMessageForPayload(Object payload, Session session,
            @Nullable Object conversionHint) throws JMSException {

        return this.payloadConverter.toMessage(payload, session);
    }

    protected final MessageHeaders extractHeaders(javax.jms.Message message) {
        return this.headerMapper.toHeaders(message);
    }

}