GB2312转成UTF-8

public static String convertStringUTF(String gbk) {
		String utf8 = gbk;
		try {
			if (!utf8.equals("") && utf8 != null) {
				utf8 = new String(gbk2utf8(gbk), "UTF-8");
			}
		} catch (UnsupportedEncodingException e) {
			utf8 = gbk;
		}
		return utf8;
	}

	public static byte[] gbk2utf8(String chenese) {
		char c[] = chenese.toCharArray();
		byte[] fullByte = new byte[3 * c.length];
		for (int i = 0; i < c.length; i++) {
			int m = (int) c[i];
			String word = Integer.toBinaryString(m);

			StringBuffer sb = new StringBuffer();
			int len = 16 - word.length();
			for (int j = 0; j < len; j++) {
				sb.append("0");
			}
			sb.append(word);
			sb.insert(0, "1110");
			sb.insert(8, "10");
			sb.insert(16, "10");

			String s1 = sb.substring(0, 8);
			String s2 = sb.substring(8, 16);
			String s3 = sb.substring(16);

			byte b0 = Integer.valueOf(s1, 2).byteValue();
			byte b1 = Integer.valueOf(s2, 2).byteValue();
			byte b2 = Integer.valueOf(s3, 2).byteValue();
			byte[] bf = new byte[3];
			bf[0] = b0;
			fullByte[i * 3] = bf[0];
			bf[1] = b1;
			fullByte[i * 3 + 1] = bf[1];
			bf[2] = b2;
			fullByte[i * 3 + 2] = bf[2];

		}
		return fullByte;
	}