原因
用Java调用雪球的API，结果返回的是乱码，一番研究后发现是因为返回的数据使用了GZIP压缩，需要先解压才能得到正确数据。
思路
使用了GZIP压缩的数据在响应头里会有一项名为content-encoding的参数，值为gzip。
Java中可以使用.getHeaderField()读取响应头的参数。
如果没有这项参数，会返回null。
解决方法
用.getHeaderField("content-encoding")读取content-encoding参数的值。
如果值不为空，通过值判断是否用了gzip压缩。
使用了gzip就解压，没用就不处理。
代码
关键部分
代码语言：java复制// 获取响应头content-encoding数据，如果是gzip就解压（以后可能要改成部分对比.contains()而不是全部对比）
String contentEncoding = conn.getHeaderField("content-encoding");
if((contentEncoding != null)&&(contentEncoding.equals("gzip"))){
is = new GZIPInputStream(conn.getInputStream());
}else{
is = conn.getInputStream();
}完整代码
- 部分地方需要按需修改
import java.io.*;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.zip.GZIPInputStream;
public class HttpURLConnectionTools {
public String doPost(String URL, String jsonStr) {
OutputStreamWriter out = null;
BufferedReader in = null;
InputStream is = null;
StringBuilder result = new StringBuilder();
HttpURLConnection conn = null;
try {
java.net.URL url = new URL(URL);
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
// 发送POST请求必须设置为true
conn.setDoOutput(true);
conn.setDoInput(true);
// 设置连接超时时间和读取超时时间
conn.setConnectTimeout(30000);
conn.setReadTimeout(10000);
conn.setRequestProperty("Content-Type", "application/json");
conn.setRequestProperty("Accept", "application/json");
// 获取输出流
out = new OutputStreamWriter(conn.getOutputStream());
out.write(jsonStr);
out.flush();
out.close();
// 取得输入流，并使用Reader读取
if (200 == conn.getResponseCode()) {
// 获取响应头content-encoding数据，如果是gzip就解压（以后可能要改成部分对比.contains()而不是全部对比）
String contentEncoding = conn.getHeaderField("content-encoding");
if((contentEncoding != null)&&(contentEncoding.equals("gzip"))){
is = new GZIPInputStream(conn.getInputStream());
}else{
is = conn.getInputStream();
}
in = new BufferedReader(new InputStreamReader(is, "UTF-8"));
String line;
while ((line = in.readLine()) != null) {
result.append(line);
System.out.println(line);
}
} else {
System.out.println("ResponseCode is an error code:" conn.getResponseCode());
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (out != null) {
out.close();
}
if (in != null) {
in.close();
}
} catch (IOException ioe) {
ioe.printStackTrace();
}
}
return result.toString();
}
public String doGet(String URL) {
HttpURLConnection conn = null;
InputStream is = null;
BufferedReader br = null;
StringBuilder result = new StringBuilder();
try {
// 创建远程url连接对象
URL url = new URL(URL);
// 通过远程url连接对象打开一个连接，强转成HTTPURLConnection类
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
// 设置连接超时时间和读取超时时间
conn.setConnectTimeout(15000);
conn.setReadTimeout(60000);
conn.setRequestProperty("accept-encoding","gzip, deflate, br");
conn.setRequestProperty("User-agent","Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.102 Safari/537.36 Edg/98.0.1108.62");
// 发送请求
conn.connect();
// 通过conn取得输入流，并使用Reader读取
if (200 == conn.getResponseCode()) {
// 获取响应头content-encoding数据，如果是gzip就解压（以后可能要改成部分对比.contains()而不是全部对比）
String contentEncoding = conn.getHeaderField("content-encoding");
if((contentEncoding != null)&&(contentEncoding.equals("gzip"))){
is = new GZIPInputStream(conn.getInputStream());
}else{
is = conn.getInputStream();
}
br = new BufferedReader(new InputStreamReader(is, "UTF-8"));
String line;
while ((line = br.readLine()) != null) {
result.append(line);
System.out.println(line);
}
} else {
System.out.println("ResponseCode is an error code:" conn.getResponseCode());
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (br != null) {
br.close();
}
if (is != null) {
is.close();
}
} catch (IOException ioe) {
ioe.printStackTrace();
}
conn.disconnect();
}
return result.toString();
}
public static void main(String[] args) {
System.out.println(new HttpURLConnectionTools().doGet("https://api.66mz8.com/api/weather.php?location=北京"));
System.out.println(new HttpURLConnectionTools().doGet("http://api.wpbom.com/api/neran.php"));
}
}博客原文：https://www.9kr.cc/archives/144/
