java 如何使用 utf8 字符正确读取 url 内容？
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How to correctly read url content with utf8 chars?
提问by Infinity
public class URLReader {
public static byte[] read(String from, String to, String string){
try {
String text = "http://translate.google.com/translate_a/t?"+
"client=o&text="+URLEncoder.encode(string, "UTF-8")+
"&hl=en&sl="+from+"&tl="+to+"";
URL url = new URL(text);
BufferedReader in = new BufferedReader(
new InputStreamReader(url.openStream(), "UTF-8"));
String json = in.readLine();
byte[] bytes = json.getBytes("UTF-8");
in.close();
return bytes;
//return text.getBytes();
}
catch (Exception e) {
return null;
}
}
}
and:
和：
public class AbcServlet extends HttpServlet {
public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
resp.setContentType("text/plain;charset=UTF-8");
resp.getWriter().println(new String(URLReader.read("pl", "en", "koń")));
}
}
When I run this i get:{"sentences"[{"trans":"end","orig":"ko???","translit":"","src_translit":""}],"src":"pl","server_time":30}so utf doesnt work correctly but if i return encoded url: http://translate.google.com/translate_a/t?client=o&text=ko%C5%84&hl=en&sl=pl&tl=enand paste at url bar i get correctly:{"sentences":[{"trans":"horse","orig":"koń","translit":"","src_translit":""}],"dict":[{"pos":"noun","terms":["horse"]}],"src":"pl","server_time":76}
当我运行它时，我得到：{"sentences"[{"trans":"end","orig":"ko???","translit":"","src_translit":""}],"src":"pl","server_time":30}所以 utf 不能正常工作，但如果我返回编码的 url:http://translate.google.com/translate_a/t?client=o&text=ko%C5%84&hl=en&sl=pl&tl=en并粘贴到 url 栏我得到正确的：{"sentences":[{"trans":"horse","orig":"koń","translit":"","src_translit":""}],"dict":[{"pos":"noun","terms":["horse"]}],"src":"pl","server_time":76}
回答by gigadot
byte[] bytes = json.getBytes("UTF-8");
gives you a UTF-8 bytes sequences so URLReader.read also give you UTF-8 bytes sequences
给你一个 UTF-8 字节序列，所以 URLReader.read 也给你 UTF-8 字节序列
but you tried to decode with without specifying the encoder, i.e. new String(URLReader.read("pl", "en", "koń"))so Java will use your system default encoding to decode (which is not UTF-8)
但是您尝试在不指定编码器的new String(URLReader.read("pl", "en", "koń"))情况下进行解码，即因此 Java 将使用您的系统默认编码进行解码（这不是 UTF-8）
Try :
尝试 ：
new String(URLReader.read("pl", "en", "koń"), "UTF-8")
Update
更新
Here is fully working code on my machine:
这是我机器上的完整代码：
public class URLReader {
public static byte[] read(String from, String to, String string) {
try {
String text = "http://translate.google.com/translate_a/t?"
+ "client=o&text=" + URLEncoder.encode(string, "UTF-8")
+ "&hl=en&sl=" + from + "&tl=" + to + "";
URL url = new URL(text);
URLConnection conn = url.openConnection();
// Look like faking the request coming from Web browser solve 403 error
conn.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows; U; Windows NT 6.1; en-GB; rv:1.9.2.13) Gecko/20101203 Firefox/3.6.13 (.NET CLR 3.5.30729)");
BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream(), "UTF-8"));
String json = in.readLine();
byte[] bytes = json.getBytes("UTF-8");
in.close();
return bytes;
//return text.getBytes();
} catch (Exception e) {
System.out.println(e);
// becarful with returning null. subsequence call will return NullPointException.
return null;
}
}
}
Don't forget to escape ń to \u0144. Java compiler may not compile Unicode text properly so it is good idea to write it in plain ASCII.
不要忘记将 ń 转义到 \u0144。Java 编译器可能无法正确编译 Unicode 文本，因此最好用纯 ASCII 编写它。
public class AbcServlet extends HttpServlet {
@Override
public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
resp.setContentType("text/plain;charset=UTF-8");
byte[] read = URLReader.read("pl", "en", "ko\u0144");
resp.getOutputStream().write(read) ;
}
}
