decrypt Unzip - Java File Path IO

Java examples for File Path IO:Zip File

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Description

decrypt Unzip

Demo Code


//package com.java2s;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.Key;
import java.security.SecureRandom;

import java.util.Enumeration;

import java.util.UUID;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

import javax.crypto.Cipher;

import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class Main {
    public static void decryptUnzip(String srcFile, String target,
            String keyFile) throws Exception {
        File temp = new File(UUID.randomUUID().toString() + ".zip");
        temp.deleteOnExit();/* w  w w  . j a v  a 2s . co  m*/
        decrypt(srcFile, temp.getAbsolutePath(), getKey(keyFile));
        unzip(temp.getAbsolutePath(), target);
        temp.delete();
    }

    public static void decrypt(String srcFile, String destFile,
            Key privateKey) throws Exception {
        SecureRandom sr = new SecureRandom();
        Cipher ciphers = Cipher.getInstance("AES/CBC/PKCS5Padding");
        IvParameterSpec spec = new IvParameterSpec(privateKey.getEncoded());
        ciphers.init(Cipher.DECRYPT_MODE, privateKey, spec, sr);
        FileInputStream fis = new FileInputStream(srcFile);
        FileOutputStream fos = new FileOutputStream(destFile);
        byte[] b = new byte[2064];
        int byteread = 0;
        while ((byteread = fis.read(b)) != -1) {
            fos.write(ciphers.doFinal(b, 0, byteread));
        }
        fos.close();
        fis.close();
    }

    public static Key getKey(String keyPath) throws Exception {
        FileInputStream fis = new FileInputStream(keyPath);
        byte[] b = new byte[16];
        fis.read(b);
        SecretKeySpec dks = new SecretKeySpec(b, "AES");
        fis.close();
        return dks;
    }

    public static void unzip(String zipFileName, String target)
            throws Exception {
        ZipFile zipfile = new ZipFile(zipFileName);
        Enumeration subFiles = zipfile.entries();
        ZipEntry zipEntry = null;
        byte[] buf = new byte[1024];
        while (subFiles.hasMoreElements()) {
            zipEntry = (ZipEntry) subFiles.nextElement();
            if (zipEntry.isDirectory()) {
                continue;
            }
            OutputStream os = new BufferedOutputStream(
                    new FileOutputStream(getRealFileName(target,
                            zipEntry.getName())));
            InputStream is = new BufferedInputStream(
                    zipfile.getInputStream(zipEntry));
            int readLen = 0;
            while ((readLen = is.read(buf, 0, 1024)) != -1) {
                os.write(buf, 0, readLen);
            }
            is.close();
            os.close();
        }
        zipfile.close();
    }

    private static File getRealFileName(String source, String absFileName) {
        String[] dirs = absFileName.split("/");
        File file = new File(source);
        if (dirs.length > 1) {
            for (int i = 0; i < dirs.length - 1; i++) {
                file = new File(file, dirs[i]);
            }
        }
        if (!file.exists()) {
            file.mkdirs();
        }
        file = new File(file, dirs[dirs.length - 1]);
        return file;
    }
}

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