restemplate请求乱码之content-encoding=“gzip“示例详解

content-encoding="gzip"
content-type="application/json;charset=UTF-8"

/**
     * @Title: getClimateByRequst
     * @Description: ( 通过request 获取天气信息)
     * @Author:lijie
     * @since 2021/11/9 14:05
     * @Version:1.1.0
     * @return:   climate:封装的天气结果类
     */
public Result<Climate> getClimateByRequst(HttpServletRequest request) {
    Result<Climate> result=new Result<>();
    try{
        //通过request请求获得ip地址
        String ip = WebUtils.getIpByRequset(request);
        //通过ip获得大致定位
        Result<Map<String, Object>> locationByIP = this.getLocationByIP(ip);
        if(locationByIP!=null&&locationByIP.isSuccess()){
            Map<String, Object> data = locationByIP.getData();
            String url=""//请求的url地址
            if(MapUtils.isNotEmpty(data)){
                String jd = MapUtils.getString(data, "jd");//精度
                String wd = MapUtils.getString(data, "wd");//纬度
                HttpHeaders httpHeaders = new HttpHeaders();
                // Accept 表示客户端支持什么格式的响应体
                httpHeaders.set("contentType", "application/json;charset=UTF-8");
                // Accept-Encoding 头，表示客户端可以接收gzip格式的压缩
                httpHeaders.set(HttpHeaders.ACCEPT_ENCODING, "gzip");
                //发送请求 
                ResponseEntity<byte[]> forEntity = restTemplate.exchange
                        (url, HttpMethod.GET, new HttpEntity<>(httpHeaders), byte[].class);
                if(forEntity.getStatusCode()== HttpStatus.OK){
                    // 获取服务器响应体编码
                    String contentEncoding = forEntity.getHeaders().getFirst(HttpHeaders.CONTENT_ENCODING);
                    if ("gzip".equals(contentEncoding)) { // 是gzip编码
                        // gzip解压服务器的Body响应体
                        byte[] weatherData = WebUtils.unGZip(
                                new ByteArrayInputStream(Objects.requireNonNull(forEntity.getBody())));
                        String weatherJson = new String(weatherData, StandardCharsets.UTF_8);
                        Climate climate = JSONObject.parseObject(weatherJson, Climate.class);
                        if(climate!=null){
                            result.setSuccess();
                            result.setData(climate);
                        }
                    } else {
                        // todo 其他的编码
                        result.setErrored("和风API响应值编码不是Gzip，请联系我，谢谢");
                    }
                }else{
                    result.setErrored("和风API响应出错了");
                }
            }
        }
    }catch (Exception e){
        result.setErrored("天气获取出错了");
    }
    return result;
}

/**
	 * Gzip解压缩
	 * @param inputStream
	 * @return
	 * @throws IOException
	 */
	public static byte[] unGZip(InputStream inputStream) throws IOException {
		ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
		try (GZIPInputStream gzipInputStream = new GZIPInputStream(inputStream)) {
			byte[] buf = new byte[4096];
			int len = -1;
			while ((len = gzipInputStream.read(buf, 0, buf.length)) != -1) {
				byteArrayOutputStream.write(buf, 0, len);
			}
			return byteArrayOutputStream.toByteArray();
		} finally {
			byteArrayOutputStream.close();
		}
	}
/**
	 * Gzip压缩数据
	 * @param data
	 * @return
	 * @throws IOException
	 */
	public static byte[] gZip(byte[] data) throws IOException {
		ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
		try (GZIPOutputStream gzipOutputStream = new GZIPOutputStream(byteArrayOutputStream)) {
			gzipOutputStream.write(data);
			gzipOutputStream.finish();
			return byteArrayOutputStream.toByteArray();
		}
	}

server:
  compression:
    # 开启响应压缩
    enabled: true
  # 支持的压缩类型
  mime-types: 
    - application/json
    - application/xml
    - application/javascript
    - text/html
    - text/xml
    - text/plain
    - text/css
    - text/javascript
  # 默认只有响应体大于 2028kb 时才会进行压缩
  min-response-size: 2048
  # 指定不压缩的user-agent，默认为null
  # excluded-user-agents