获取字符串的编码、修改字符串编码

    // 获取字符串的编码
    public static String getEncoding(String str) {
        String encode = "GB2312";
        try {
            if (str.equals(new String(str.getBytes(encode), encode))) {
                String s = encode;
                return s;
            }
        } catch (Exception exception) {
        }
        encode = "ISO-8859-1";
        try {
            if (str.equals(new String(str.getBytes(encode), encode))) {
                String s1 = encode;
                return s1;
            }
        } catch (Exception exception1) {
        }
        encode = "UTF-8";
        try {
            if (str.equals(new String(str.getBytes(encode), encode))) {
                String s2 = encode;
                return s2;
            }
        } catch (Exception exception2) {
        }
        encode = "GBK";
        try {
            if (str.equals(new String(str.getBytes(encode), encode))) {
                String s3 = encode;
                return s3;
            }
        } catch (Exception exception3) {
        }
        return "";
    }
2.将字符串编码转为指定编码，如转为gbk
public String changEncod(){String str}{
　　　　String fileDir = "d:/str.txt";

　　　　String str = txt2String(fileDir);

　　　　//获取原编码
　　　　String encod = getEncoding(str);

　　　　//转为gbk
　　　　String s = new String(str.getBytes(encod),"gbk");

}
3.获取字符串内容

public static String txt2String(String filePath) {
File file = new File(filePath);
StringBuilder result = new StringBuilder();
try {
BufferedReader br = new BufferedReader(new FileReader(file));// 构造一个BufferedReader类来读取文件
String s = null;
while ((s = br.readLine()) != null) {// 使用readLine方法，一次读一行
result.append(System.lineSeparator() + s);
}
br.close();
} catch (Exception e) {
e.printStackTrace();
}
return result.toString();
}

//改字符串编码
public static String changeCharset(String str, String newCharset)
throws UnsupportedEncodingException {
if (str != null) {
// 用默认字符编码解码字符串。
byte[] bs = str.getBytes();
// 用新的字符编码生成字符串
return new String(bs, newCharset);
}
return null;
}