SHA1WithRSA 验证数字签名

public class SignProvider {
    private SignProvider() {

    }

    /**
     * 
     * Description:校验数字签名,此方法不会抛出任务异常,成功返回true,失败返回false,要求全部参数不能为空
     * 
     * @param pubKeyText
     *            公钥,base64编码
     * @param plainText
     *            明文
     * @param signTest
     *            数字签名的密文,base64编码
     * @return 校验成功返回true 失败返回false
     * @author 孙钰佳
     * @since：2007-12-27 上午09:33:55
     */
    public static boolean verify(byte[] pubKeyText, String plainText,
            byte[] signText) {
        try {
            // 取公钥匙对象
            java.security.PublicKey pubKey = getPublicKey(Base64
                    .decode(pubKeyText));
            // 解密由base64编码的数字签名
            byte[] signed = Base64.decode(signText);
            java.security.Signature signatureChecker = java.security.Signature
                    .getInstance("SHA1WithRSA");
            signatureChecker.initVerify(pubKey);
            signatureChecker.update(plainText.getBytes());
            // 验证签名是否正常
            if (signatureChecker.verify(signed))
                return true;
            else
                return false;
        } catch (Throwable e) {
            System.out.println("校验签名失败");
            e.printStackTrace();
            return false;
        }
    }

    /**
     * 从公钥数据取得公钥
     * 
     * @param bPubKeyInput
     * @return
     */
    public static PublicKey getPublicKey(byte[] bPubKeyInput) {
        PublicKey rsaPubKey = null;
        byte[] bX509PubKeyHeader = { 48, -127, -97, 48, 13, 6, 9, 42, -122, 72,
                -122, -9, 13, 1, 1, 1, 5, 0, 3, -127, -115, 0 };
        try {
            byte[] bPubKey = new byte[bPubKeyInput.length
                    + bX509PubKeyHeader.length];
            System.arraycopy(bX509PubKeyHeader, 0, bPubKey, 0,
                    bX509PubKeyHeader.length);
            System.arraycopy(bPubKeyInput, 0, bPubKey,
                    bX509PubKeyHeader.length, bPubKeyInput.length);

            X509EncodedKeySpec rsaKeySpec = new X509EncodedKeySpec(bPubKey);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            rsaPubKey = keyFactory.generatePublic(rsaKeySpec);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return rsaPubKey;
    }
}
 这里要注意一些情况下根据公钥串取公约对象时要进行补码,当初因为不知道这个地方,郁闷了好久.嗨.....