本文采用AES加密方式对文件内容进行加密，AES效率高。
以下是AES的工具类，拿来即可使用，方便快捷
package cn.gs.core.common.utils;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.CipherInputStream;
import javax.crypto.CipherOutputStream;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import javax.servlet.ServletOutputStream;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class AES {
private final static Logger logger = LoggerFactory.getLogger(AES.class);
public static String cKey = "1fc3351d-7b05-440f-8f0b-be4caef0b944";
public static byte[] encrypt(String content, String sKey) {
try {
// 初始化 加密器
Cipher cipher = initAESCipher(sKey, Cipher.ENCRYPT_MODE);
byte[] byteContent = content.getBytes("utf-8");
byte[] result = cipher.doFinal(byteContent);
return result; // 加密
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IllegalBlockSizeException e) {
e.printStackTrace();
} catch (BadPaddingException e) {
e.printStackTrace();
}
return null;
}
public static byte[] decrypt(byte[] content, String sKey) {
try {
// 初始化 加密器
Cipher cipher = initAESCipher(sKey, Cipher.DECRYPT_MODE);
byte[] result = cipher.doFinal(content);
return result; // 加密
} catch (IllegalBlockSizeException e) {
e.printStackTrace();
} catch (BadPaddingException e) {
e.printStackTrace();
}
return null;
}
public static File encryptFile(File sourceFile, File encrypfile, String sKey) {
InputStream inputStream = null;
OutputStream outputStream = null;
try {
inputStream = new FileInputStream(sourceFile);
outputStream = new FileOutputStream(encrypfile);
Cipher cipher = initAESCipher(sKey, Cipher.ENCRYPT_MODE);
// 以加密流写入文件
CipherInputStream cipherInputStream = new CipherInputStream(inputStream, cipher);
byte[] cache = new byte[1024];
int nRead = 0;
while ((nRead = cipherInputStream.read(cache)) != -1) {
outputStream.write(cache, 0, nRead);
outputStream.flush();
}
cipherInputStream.close();
} catch (FileNotFoundException e) {
e.printStackTrace(); // To change body of catch statement use File |
// Settings | File Templates.
} catch (IOException e) {
e.printStackTrace(); // To change body of catch statement use File |
// Settings | File Templates.
} finally {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace(); // To change body of catch statement use
// File | Settings | File Templates.
}
try {
outputStream.close();
} catch (IOException e) {
e.printStackTrace(); // To change body of catch statement use
// File | Settings | File Templates.
}
}
return encrypfile;
}
public static File encryptFile(InputStream inputStream, File encrypfile, String sKey) {
OutputStream outputStream = null;
try {
outputStream = new FileOutputStream(encrypfile);
Cipher cipher = initAESCipher(sKey, Cipher.ENCRYPT_MODE);
// 以加密流写入文件
CipherInputStream cipherInputStream = new CipherInputStream(inputStream, cipher);
byte[] cache = new byte[1024];
int nRead = 0;
while ((nRead = cipherInputStream.read(cache)) != -1) {
outputStream.write(cache, 0, nRead);
outputStream.flush();
}
cipherInputStream.close();
} catch (FileNotFoundException e) {
e.printStackTrace(); // To change body of catch statement use File |
// Settings | File Templates.
} catch (IOException e) {
e.printStackTrace(); // To change body of catch statement use File |
// Settings | File Templates.
} finally {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace(); // To change body of catch statement use
// File | Settings | File Templates.
}
try {
outputStream.close();
} catch (IOException e) {
e.printStackTrace(); // To change body of catch statement use
// File | Settings | File Templates.
}
}
return encrypfile;
}
public static File decryptFile(File sourceFile, File decryptFile, String sKey) {
InputStream inputStream = null;
OutputStream outputStream = null;
try {
Cipher cipher = initAESCipher(sKey, Cipher.DECRYPT_MODE);
inputStream = new FileInputStream(sourceFile);
outputStream = new FileOutputStream(decryptFile);
CipherOutputStream cipherOutputStream = new CipherOutputStream(outputStream, cipher);
byte[] buffer = new byte[1024];
int r;
while ((r = inputStream.read(buffer)) >= 0) {
cipherOutputStream.write(buffer, 0, r);
}
cipherOutputStream.close();
} catch (IOException e) {
logger.info("IOException");
logger.info(e.getMessage());
logger.info(e.getLocalizedMessage());
e.printStackTrace(); // To change body of catch statement use File |
// Settings | File Templates.
} finally {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace(); // To change body of catch statement use
// File | Settings | File Templates.
}
try {
outputStream.close();
} catch (IOException e) {
e.printStackTrace(); // To change body of catch statement use
// File | Settings | File Templates.
}
}
return decryptFile;
}
public static OutputStream decryptFile(File sourceFile,ServletOutputStream outputStream, String sKey) {
InputStream inputStream = null;
try {
Cipher cipher = initAESCipher(sKey, Cipher.DECRYPT_MODE);
inputStream = new FileInputStream(sourceFile);
CipherOutputStream cipherOutputStream = new CipherOutputStream(outputStream, cipher);
byte[] buffer = new byte[1024];
int r;
while ((r = inputStream.read(buffer)) >= 0) {
cipherOutputStream.write(buffer, 0, r);
}
cipherOutputStream.close();
} catch (IOException e) {
e.printStackTrace(); // To change body of catch statement use File |
// Settings | File Templates.
} finally {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace(); // To change body of catch statement use
// File | Settings | File Templates.
}
try {
outputStream.close();
} catch (IOException e) {
e.printStackTrace(); // To change body of catch statement use
// File | Settings | File Templates.
}
}
return outputStream;
}
public static Cipher initAESCipher(String sKey, int cipherMode) {
// 创建Key gen
KeyGenerator keyGenerator = null;
Cipher cipher = null;
try {
keyGenerator = KeyGenerator.getInstance( "AES" );
SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG" );
secureRandom.setSeed(sKey.getBytes());
keyGenerator.init(128, secureRandom);
SecretKey secretKey = keyGenerator.generateKey();
byte[] codeFormat = secretKey.getEncoded();
SecretKeySpec key = new SecretKeySpec(codeFormat, "AES");
cipher = Cipher.getInstance("AES");
cipher.init(cipherMode, key);
} catch (NoSuchAlgorithmException e) {
e.printStackTrace(); // To change body of catch statement use File |
// Settings | File Templates.
} catch (NoSuchPaddingException e) {
e.printStackTrace(); // To change body of catch statement use File |
// Settings | File Templates.
} catch (InvalidKeyException e) {
e.printStackTrace(); // To change body of catch statement use File |
// Settings | File Templates.
}
return cipher;
}
public static File encryptFile(String oldfilePath, String encrypfilePath) {
File oldfile = new File(oldfilePath);// 未加密文件路径
File encrypfile = new File(encrypfilePath);// 加密后的文件路径
return encryptFile(oldfile, encrypfile, cKey);// 加密文件
}
public static File decryptFile(String encrypfilePath, String decrypfilePath) {
File encrypfile = new File(encrypfilePath);// 加密后的文件路径
File decrypfile = new File(decrypfilePath);// 解密后的文件路径
return decryptFile(encrypfile, decrypfile, cKey);// 解密文件
}
public static void main(String[] args) throws Exception {
File oldfile = new File("D://123.pdf");// 未加密文件路径
File encrypfile = new File("D://123-e.pdf");// 加密后的文件路径
File decrypfile = new File("D://123-d.pdf");// 解密后的文件路径
encryptFile(oldfile, encrypfile, cKey);// 加密文件
decryptFile(encrypfile, decrypfile, cKey);// 解密文件
}
}
