Question

对于我的3DES加密算法，将FileInputStream和FileOutputStream转换为CipherInputStream和CipherOutputStream时遇到一些问题。有人可以指导我正确的方法吗？我最终收到错误：“ CipherInputStream无法解析为类型”。抱歉，这很明显。

t.prototype.downloadXlsx = function () {
            var t = this, e = {
                date_from: this.helpers.formatDate(this.filter.date_from),
                date_to: this.helpers.formatDate(this.filter.date_to),
                download: "fees"
            };
            this.http.get("team-accounts/" + this.route.snapshot.params.id, e).subscribe(function (n) {
                var i = {type: 'application/octet-stream'},
                    r = t.account.team.name + "_summary_" + e.date_from + "_" + e.date_to + ".xlsx";
                t.helpers.downloadXlsxFile(n._body, i, r);
            })

t.prototype.downloadXlsxFile = function (t, e, n, i) {
            var r = new Blob(t], e);
            if (navigator.msSaveBlob) navigator.msSaveBlob(r, n); else {
                var a = document.createElement("a");
                if (void 0 !== a.download) {
                    var o = i || document.body, s = URL.createObjectURL(r);
                    a.setAttribute("href", s), a.setAttribute("download", n), a.style.visibility = "hidden", o.appendChild(a), a.click(), o.removeChild(a)
                }
            }

Answer 1

这对我有用：

public class Cypher {

    // password to encrypt the file
    private static final String passKey = "tkfhkggovubm";

    public static void main(String[] args) throws Exception {

        try (FileInputStream inputFile = new FileInputStream("plainfile.txt");
                FileOutputStream outputFile = new FileOutputStream("plainfile.des");) {

            byte[] salt = new byte[8];
            SecureRandom r = new SecureRandom();
            r.nextBytes(salt);

            outputFile.write(salt);

            PBEKeySpec pbeKeySpec = new PBEKeySpec(passKey.toCharArray());
            SecretKeyFactory secretKeyFactory = SecretKeyFactory
                    .getInstance("PBEWithSHA1AndDESede");
            SecretKey secretKey = secretKeyFactory.generateSecret(pbeKeySpec);

            PBEParameterSpec pbeParameterSpec = new PBEParameterSpec(salt, 99999);
            Cipher cipher = Cipher.getInstance("PBEWithSHA1AndDESede");
            cipher.init(Cipher.ENCRYPT_MODE, secretKey, pbeParameterSpec);

            try (CipherOutputStream cis = new CipherOutputStream(outputFile, cipher);) {
                IOUtils.copy(inputFile, cis);
            }
        }

        try (FileInputStream fis = new FileInputStream("plainfile.des");
                FileOutputStream outputFile = new FileOutputStream("plainfile.txt2");) {
            byte[] salt = new byte[8];
            int saltBytes = fis.read(salt);
            if (saltBytes!=salt.length)
                throw new Exception("Huh???");

            PBEKeySpec pbeKeySpec = new PBEKeySpec(passKey.toCharArray());
            SecretKeyFactory secretKeyFactory = SecretKeyFactory
                    .getInstance("PBEWithSHA1AndDESede");
            SecretKey secretKey = secretKeyFactory.generateSecret(pbeKeySpec);

            PBEParameterSpec pbeParameterSpec = new PBEParameterSpec(salt, 99999);
            Cipher cipher = Cipher.getInstance("PBEWithSHA1AndDESede");
            cipher.init(Cipher.DECRYPT_MODE, secretKey, pbeParameterSpec);

            try (CipherInputStream cis = new CipherInputStream(fis, cipher);) {
                IOUtils.copy(cis, outputFile);
            }
        }
    }
}

执行完主体后，plainfile.txt和plainfile.txt2相等。 plainfile.des被加密。

IOUtils.copy是apache.commons-io中的一种方法，该方法在内部保留缓冲区，并将所有字节从一个流写入另一个流。只是将byte[] input = ...提取到方法中，再加上使用try-with-resources。这样可以使代码简单易读。

需要帮助实现CipherInputStream和CipherOutputStream

1 个答案: