com.alta189.deskbin.util.CryptUtils.java Source code

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Here is the source code for com.alta189.deskbin.util.CryptUtils.java

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/*
 * This file is part of DeskBin.
 *
 * Copyright (c) 2012, alta189 <http://github.com/alta189/DeskBin/>
 * DeskBin is licensed under the GNU Lesser General Public License.
 *
 * DeskBin is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * DeskBin is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package com.alta189.deskbin.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

import javax.crypto.SecretKey;

import org.apache.commons.io.IOUtils;

public class CryptUtils {
    private static SecretKey key;
    public static File keyFile = new File(PlatformUtils.getWorkingDirectory(), "data" + File.separator + "key");
    private static DesEncrypter encrypter;

    private static boolean loadKey() {
        FileInputStream fis = null;
        ObjectInputStream in = null;
        try {
            fis = new FileInputStream(keyFile);
            in = new ObjectInputStream(fis);
            Object obj = in.readObject();
            if (obj != null && obj instanceof SecretKey) {
                key = (SecretKey) obj;
                return true;
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            IOUtils.closeQuietly(fis);
            IOUtils.closeQuietly(in);
        }
        return false;
    }

    private static SecretKey getNewSecretKey() {
        return DesEncrypter.getNewKey();
    }

    private static boolean writeKey(SecretKey key) {
        FileOutputStream fos = null;
        ObjectOutputStream out = null;
        try {
            if (keyFile.getParentFile() != null) {
                keyFile.getParentFile().mkdirs();
            }
            fos = new FileOutputStream(keyFile);
            out = new ObjectOutputStream(fos);
            out.writeObject(key);
            out.flush();
            return true;
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            IOUtils.closeQuietly(fos);
            IOUtils.closeQuietly(out);
        }
        return false;
    }

    public static SecretKey getSecretKey() {
        if (key != null) {
            return key;
        }
        SecretKey compare = null;
        if (!keyFile.exists()) {
            compare = getNewSecretKey();
            if (!writeKey(compare)) {
                return null;
            }
        }
        if (loadKey()) {
            if (compare != null && !compare.equals(key)) {
                key = null;
            }
            return key;
        }
        return null;
    }

    private static DesEncrypter getEncrypter() {
        if (encrypter != null) {
            return encrypter;
        }

        encrypter = new DesEncrypter(getSecretKey());
        return encrypter;
    }

    public static String encrypt(String raw) {
        return getEncrypter().encrypt(raw);
    }

    public static String decrypt(String raw) {
        return getEncrypter().decrypt(raw);
    }

}