[ISSUE #147]An enhancement about the convert in RocketMQTemplate

[zkzlx]

What is the purpose of the change

An enhancement about the convert in RocketMQTemplate

Brief changelog

enhancement #147

Do not use ObjectMapper directly, Instead, the externally built converter is injected into MessageConverter in RocketMQTemplate.

a piece of code in RocketMQMessageConverter :

public RocketMQMessageConverter() {
	List<MessageConverter> messageConverters = new ArrayList<>();
	ByteArrayMessageConverter byteArrayMessageConverter = new ByteArrayMessageConverter();
	byteArrayMessageConverter.setContentTypeResolver(null);
	messageConverters.add(byteArrayMessageConverter);
	messageConverters.add(new StringMessageConverter());
	if (JACKSON_PRESENT) {
		messageConverters.add(new MappingJackson2MessageConverter());
	}
	if (FASTJSON_PRESENT) {
		try {
			messageConverters.add(
				(MessageConverter)ClassUtils.forName(
					"com.alibaba.fastjson.support.spring.messaging.MappingFastJsonMessageConverter",
					ClassUtils.getDefaultClassLoader()).newInstance());
		} catch (ClassNotFoundException | IllegalAccessException | InstantiationException e) {
		}
	}
	messageConverter = new CompositeMessageConverter(messageConverters);
}

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[zkzlx]

@vongosling Please take a look

[zkzlx]

@RongtongJin @vongosling I was solved , you can check it now. thanks .

[RongtongJin]

LGTM~