自定义HttpMessageConverter

1.继承AbstractHttpMessageConverter类

2.构造函数新建媒体类型

3.重写readInternal方法，处理请求参数

4.重写supports方法，表示该MessageConverter只处理该对象

5.重写writeInternal方法，处理数据输出到页面上

package com.lebron.springmvc;import java.io.IOException;import java.nio.charset.Charset;import org.springframework.http.HttpInputMessage;import org.springframework.http.HttpOutputMessage;import org.springframework.http.MediaType;import org.springframework.http.converter.AbstractHttpMessageConverter;import org.springframework.http.converter.HttpMessageNotReadableException;import org.springframework.http.converter.HttpMessageNotWritableException;import org.springframework.util.StreamUtils;public class MyDateMessageConverter extends AbstractHttpMessageConverter<MyDate>{    public MyDateMessageConverter(){        super(new MediaType("application", "my-date", Charset.forName("UTF-8")));    }        @Override    protected MyDate readInternal(Class<? extends MyDate> clazz, HttpInputMessage inputMessage) throws IOException, HttpMessageNotReadableException {        String temp = StreamUtils.copyToString(inputMessage.getBody(), Charset.forName("UTF-8"));        String[] tempArr = temp.split("/");        return new MyDate(new Integer(tempArr[0]),new Integer(tempArr[1]),new Integer(tempArr[2]));    }        @Override    protected boolean supports(Class<?> clazz) {        return MyDate.class.isAssignableFrom(clazz);    }    @Override    protected void writeInternal(MyDate myDate, HttpOutputMessage outputMessage) throws IOException, HttpMessageNotWritableException {        String out = myDate.getYear() + "/" + myDate.getMonth() + "/" + myDate.getDay();        outputMessage.getBody().write(out.getBytes());    }}

6.重写extendMessageConverters方法，将转换器添加到转换器链中（重写configureMessageConverters方法会覆盖内置的所有转换器，所以不推荐）

@Beanpublic MyMessageConverter myMessageConverter(){    return new MyMessageConverter();}@Overridepublic void extendMessageConverters(List<HttpMessageConverter<?>> converters) {    converters.add(new MyMessageConverter());}