http://hi.baidu.com/java0804ms/item/111ea834fbd4d2f596f88d5a
实现效果:对文件内容进行加密,使之直接打开成为乱码,不以明文显示
实现步骤:1.key.txt里面存放的是加密文件的密码,这个是明文
2.源文件加密后,加密后的文件如果是压缩包必须通过程序解密后,方可打开,直接用软件是打不开加密后的压缩文件(此处需要注意一下,例如:将test.txt加密压缩后成为新的文件test.rar,test.rar必须通过程序解密后,才能用软件打开,如果直接打开test.rar是不行的)
3.已经测试,方案可行,详情请参见代码:
实现代码如下:
package com.test;
import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.security.Key; import java.security.SecureRandom; import java.util.UUID; import java.util.zip.ZipEntry; import java.util.zip.ZipInputStream; import java.util.zip.ZipOutputStream; import javax.crypto.Cipher; import javax.crypto.KeyGenerator; import javax.crypto.SecretKey; import javax.crypto.spec.IvParameterSpec; import javax.crypto.spec.SecretKeySpec;
/** * 对文件加密/解密和压缩/解压缩对象类 */ public class test { public static void main(String args[]) throws Exception{ //自定义压缩方式 String srcFile = "c://test.rar";//源文件 String destFile = "c://test1.rar";//加密后文件 Key privateKey = new test().getKey("c://key.txt");//存放解密密码 new test().encrypt(srcFile, destFile, privateKey);//加密压缩文件(压缩后的文件必须通过程序解密才能打开) new test().decrypt(destFile, "c://text2.rar", privateKey);//解密压缩文件 } private void directoryZip(ZipOutputStream out, File f, String base) throws Exception { // 如果传入的是目录 if (f.isDirectory()) { File[] fl = f.listFiles(); // 创建压缩的子目录 out.putNextEntry(new ZipEntry(base + "/")); if (base.length() == 0) { base = ""; } else { base = base + "/"; } for (int i = 0; i < fl.length; i++) { directoryZip(out, fl[i], base + fl[i].getName()); } } else { // 把压缩文件加入rar中 out.putNextEntry(new ZipEntry(base)); FileInputStream in = new FileInputStream(f); byte[] bb = new byte[2048]; int aa = 0; while ((aa = in.read(bb)) != -1) { out.write(bb, 0, aa); } in.close(); } }
/** * 压缩文件 * * @param zos * @param file * @throws Exception */ private void fileZip(ZipOutputStream zos, File file) throws Exception { if (file.isFile()) { zos.putNextEntry(new ZipEntry(file.getName())); FileInputStream fis = new FileInputStream(file); byte[] bb = new byte[2048]; int aa = 0; while ((aa = fis.read(bb)) != -1) { zos.write(bb, 0, aa); } fis.close(); System.out.println(file.getName()); } else { directoryZip(zos, file, ""); } }
/** * 解压缩文件 * * @param zis * @param file * @throws Exception */ private void fileUnZip(ZipInputStream zis, File file) throws Exception { ZipEntry zip = zis.getNextEntry(); if (zip == null) return; String name = zip.getName(); File f = new File(file.getAbsolutePath() + "/" + name); if (zip.isDirectory()) { f.mkdirs(); fileUnZip(zis, file); } else { f.createNewFile(); FileOutputStream fos = new FileOutputStream(f); byte b[] = new byte[2048]; int aa = 0; while ((aa = zis.read(b)) != -1) { fos.write(b, 0, aa); } fos.close(); fileUnZip(zis, file); } }
/** * 对directory目录下的文件压缩,保存为指定的文件zipFile * * @param directory * @param zipFile */ private void zip(String directory, String zipFile) { try { ZipOutputStream zos = new ZipOutputStream(new FileOutputStream( zipFile)); fileZip(zos, new File(directory)); zos.close(); } catch (Exception e) { e.printStackTrace(); } }
/** * 解压缩文件zipFile保存在directory目录下 * * @param directory * @param zipFile */ private void unZip(String directory, String zipFile) { try { ZipInputStream zis = new ZipInputStream( new FileInputStream(zipFile)); File f = new File(directory); f.mkdirs(); fileUnZip(zis, f); zis.close(); } catch (Exception e) { e.printStackTrace(); } }
/** * 根据key的路径文件获得持久化成文件的key * <P> * 例子: RsaEncrypt.getKey("c:/systemkey/private.key"); * * @param keyPath * @return */ private 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; }
/** * 把文件srcFile加密后存储为destFile * * @param srcFile * @param destFile */ private void encrypt(String srcFile, String destFile, Key privateKey) throws Exception { SecureRandom sr = new SecureRandom(); Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding"); IvParameterSpec spec = new IvParameterSpec(privateKey.getEncoded()); cipher.init(Cipher.ENCRYPT_MODE, privateKey, spec, sr); FileInputStream fis = new FileInputStream(srcFile); FileOutputStream fos = new FileOutputStream(destFile); byte[] b = new byte[2048]; while (fis.read(b) != -1) { fos.write(cipher.doFinal(b)); } fos.close(); fis.close(); }
/** * 把文件srcFile解密后存储为destFile * * @param srcFile * @param destFile * @param privateKey * @throws Exception */ private 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]; while (fis.read(b) != -1) { fos.write(ciphers.doFinal(b)); } fos.close(); fis.close(); }
/** * 对目录srcFile下的所有文件目录进行先压缩后操作,然后保存为destfile * * @param srcFile * 要操作的目录 如c:/test/test * @param destfile * 压缩加密后存放的文件名 如c:/加密压缩文件.zip * @param keyfile * 公钥存放地点 */ public void encryptZip(String srcFile, String destfile, String keyfile) throws Exception { SecureRandom sr = new SecureRandom(); KeyGenerator kg = KeyGenerator.getInstance("AES"); kg.init(128, sr); SecretKey key = kg.generateKey(); File f = new File(keyfile); if (!f.getParentFile().exists()) f.getParentFile().mkdirs(); f.createNewFile(); FileOutputStream fos = new FileOutputStream(f); fos.write(key.getEncoded()); File temp = new File(UUID.randomUUID().toString() + ".zip"); temp.deleteOnExit(); // 先压缩文件 zip(srcFile, temp.getAbsolutePath()); // 对文件加密 encrypt(temp.getAbsolutePath(), destfile, key); temp.delete(); }
/** * 对文件srcfile进行先解密后解压缩,然后解压缩到目录destfile下 * * @param srcfile * 要解密和解压缩的文件名 如c:/目标.zip * @param destfile * 解压缩后的目录 如c:/abc * @param publicKey * 公钥 */ public void decryptUnzip(String srcfile, String destfile, String keyfile) throws Exception { // 先对文件解密 File temp = new File(UUID.randomUUID().toString() + ".zip"); temp.deleteOnExit(); decrypt(srcfile, temp.getAbsolutePath(), this.getKey(keyfile)); // 解压缩 unZip(destfile, temp.getAbsolutePath()); temp.delete(); } }