自定义HttpMessageConverter-向日葵屋

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）

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