import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;


public class CheckUtil {

    private static final String token = "MyToken";

    /**
     * 校验绑定微信
     */
    public static boolean checkSignature(String signature, String timestamp, String nonce) {
        String[] arr = new String[]{token, timestamp, nonce};

        Arrays.sort(arr);

        StringBuilder content = new StringBuilder();
        for (String s : arr) {
            content.append(s);
        }

        String temp = getSha1(content.toString());
        return temp.equals(signature);
    }


    /**
     * @param plainText 明文
     * @return 32位密文
     */
    public String encryption(String plainText) {
        String re_md5 = "";
        try {
            MessageDigest md = MessageDigest.getInstance("MD5");
            md.update(plainText.getBytes());
            byte b[] = md.digest();
            int i;

            StringBuilder buf = new StringBuilder();
            for (byte aB : b) {
                i = aB;
                if (i < 0)
                    i += 256;
                if (i < 16)
                    buf.append("0");
                buf.append(Integer.toHexString(i));
            }

            re_md5 = buf.toString();

        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        return re_md5;
    }

    /**
     * SHA加密
     *
     */
    private static String getSha1(String str) {
        if (str == null || str.length() == 0) {
            return null;
        }
        char hexDigits[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
                'a', 'b', 'c', 'd', 'e', 'f'};
        try {
            MessageDigest mdTemp = MessageDigest.getInstance("SHA1");
            mdTemp.update(str.getBytes("UTF-8"));

            byte[] md = mdTemp.digest();
            int j = md.length;
            char buf[] = new char[j * 2];
            int k = 0;
            for (byte byte0 : md) {
                buf[k++] = hexDigits[byte0 >>> 4 & 0xf];
                buf[k++] = hexDigits[byte0 & 0xf];
            }
            return new String(buf);
        } catch (Exception e) {
            return null;
        }
    }


}