java - 读取统一码

Question

我正在使用 java io 从可能输出 é 等字符的服务器检索文本。 然后使用System.err输出它，结果是'？'。我使用UTF8编码。怎么了？ int 长度 = 0;

char[] buffer = new char[1024];
OutputStream os = sock.getOutputStream();
InputStream is = sock.getInputStream();
os.write(query.getBytes("UTF8"));//iso8859_1"));

Reader reader = new InputStreamReader(is, Charset.forName("UTF-8"));
do {
    len = reader.read(buffer);
    if (len > 0) {
        if (outstring == null) {
            outstring = new StringBuffer();
        }
        outstring.append(buffer, 0, len);
    }
} while (len > 0);
System.err.println(outstring);

编辑:刚刚尝试了以下代码:

StringBuffer b = new StringBuffer();
for (char c = 'a'; c < 'd'; c++) {
    b.append(c);
}
b.append('\u00a5'); // Japanese Yen symbol
b.append('\u01FC'); // Roman AE with acute accent
b.append('\u0391'); // GREEK Capital Alpha
b.append('\u03A9'); // GREEK Capital Omega

for (int i = 0; i < b.length(); i++) {
    System.out.println("Character #" + i + " is " + b.charAt(i));
}
System.out.println("Accumulated characters are " + b);

结果也变成了垃圾:

Character #0 is a
Character #1 is b
Character #2 is c
Character #3 is ¥
Character #4 is ?
Character #5 is ?
Character #6 is ?
Accumulated characters are abc¥???

Answer 1

首先，验证系统属性 (file.encoding) 实际上是 UTF8。如果是，那么您的问题不是您正在运行的代码，而是您的终端程序(或其他输出显示)无法正确呈现输出。