获取txt文档编码格式

发表于 | 分类于 | 阅读次数:

网上好多不完全，总有个别txt的编码获取不到。
用这段代码，暂时没有发现问题。

它在我的机器上可以很好运行！ ——-大部分程序员

部分TXT识别不了的版本
1
2
3
4
5
6
7
8
9
10
11
12
InputStream inputStream = new FileInputStream("g62.txt");
byte[] head = new byte[3];
inputStream.read(head);
String code = "GBK";
if (head[0] == -1  &&  head[1] == -2){
    code = "UTF-16";
}else if (head[0] == -2  &&  head[1] == -1){
    code = "Unicode";
}else if (head[0] == -17  && head[1] == -69 && head[2] == -65){
    code = "UTF-8";
}
inputStream.close();
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
BufferedInputStream bin = new BufferedInputStream(new FileInputStream("62.txt"));
int p = (bin.read() << 8) + bin.read();

String code = null;

switch (p) {
    case 0xefbb:
        code = "UTF-8";
        break;
    case 0xfffe:
        code = "Unicode";
        break;
    case 0xfeff:
        code = "UTF-16BE";
        break;
    default:
        code = "GBK";
}
bin.close();
未发现问题版本
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
private static  String getFileCharset(File sourceFile) {
    String charset = "GBK";
    byte[] first3Bytes = new byte[3];
    try {
        boolean checked = false;
        BufferedInputStream bis = new BufferedInputStream(new FileInputStream(sourceFile));
        bis.mark(0);
        int read = bis.read(first3Bytes, 0, 3);
        if (read == -1) {
            return charset; //文件编码为 ANSI
        } else if (first3Bytes[0] == (byte) 0xFF
                && first3Bytes[1] == (byte) 0xFE) {
            charset = "UTF-16LE"; //文件编码为 Unicode
            checked = true;
        } else if (first3Bytes[0] == (byte) 0xFE
                && first3Bytes[1] == (byte) 0xFF) {
            charset = "UTF-16BE"; //文件编码为 Unicode big endian
            checked = true;
        } else if (first3Bytes[0] == (byte) 0xEF
                && first3Bytes[1] == (byte) 0xBB
                && first3Bytes[2] == (byte) 0xBF) {
            charset = "UTF-8"; //文件编码为 UTF-8
            checked = true;
        }
        bis.reset();
        if (!checked) {
            int loc = 0;
            while ((read = bis.read()) != -1) {
                loc++;
                if (read >= 0xF0)
                    break;
                if (0x80 <= read && read <= 0xBF) // 单独出现BF以下的，也算是GBK
                    break;
                if (0xC0 <= read && read <= 0xDF) {
                    read = bis.read();
                    if (0x80 <= read && read <= 0xBF) // 双字节 (0xC0 - 0xDF)
                        // (0x80
                        // - 0xBF),也可能在GB编码内
                        continue;
                    else
                        break;
                } else if (0xE0 <= read && read <= 0xEF) {// 也有可能出错，但是几率较小
                    read = bis.read();
                    if (0x80 <= read && read <= 0xBF) {
                        read = bis.read();
                        if (0x80 <= read && read <= 0xBF) {
                            charset = "UTF-8";
                            break;
                        } else
                            break;
                    } else
                        break;
                }
            }
        }
        bis.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
    return charset;
}