java判断字符串编码

public class JudgeCode {
	
	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 "";
	}

	public static void main(String[] args) {
		// TODO Auto-generated method stub

	}

}