/*
* Copyright (c) 2002-2012 Alibaba Group Holding Limited.
* All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.alibaba.citrus.service.requestcontext.session.encrypter;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;
import javax.crypto.Cipher;
import com.alibaba.citrus.service.requestcontext.session.encoder.SessionEncoderException;
import com.alibaba.citrus.springext.support.BeanSupport;
public abstract class AbstractJceEncrypter extends BeanSupport implements Encrypter {
public static final int DEFAULT_POOL_SIZE = 256;
private final Queue<Cipher> eciphers = new ConcurrentLinkedQueue<Cipher>();
private final Queue<Cipher> dciphers = new ConcurrentLinkedQueue<Cipher>();
private int poolSize;
public int getPoolSize() {
return poolSize <= 0 ? DEFAULT_POOL_SIZE : poolSize;
}
public void setPoolSize(int poolSize) {
this.poolSize = poolSize;
}
protected final Cipher getCipher(int mode) throws Exception {
Queue<Cipher> pool = mode == Cipher.ENCRYPT_MODE ? eciphers : dciphers;
Cipher cipher = pool.poll();
if (cipher == null) {
cipher = createCipher(mode);
}
return cipher;
}
protected final void returnCipher(int mode, Cipher cipher) {
Queue<Cipher> pool = mode == Cipher.ENCRYPT_MODE ? eciphers : dciphers;
if (cipher != null) {
pool.offer(cipher);
}
while (pool.size() > getPoolSize()) {
pool.poll();
}
}
protected abstract Cipher createCipher(int mode) throws Exception;
public byte[] encrypt(byte[] plaintext) throws SessionEncrypterException {
Cipher cipher = null;
try {
cipher = getCipher(Cipher.ENCRYPT_MODE);
return cipher.doFinal(plaintext);
} catch (Exception e) {
throw new SessionEncoderException("Failed to encrypt object", e);
} finally {
returnCipher(Cipher.ENCRYPT_MODE, cipher);
}
}
public byte[] decrypt(byte[] cryptotext) throws SessionEncrypterException {
Cipher cipher = null;
try {
cipher = getCipher(Cipher.DECRYPT_MODE);
return cipher.doFinal(cryptotext);
} catch (Exception e) {
throw new SessionEncoderException("Failed to decrypt object", e);
} finally {
returnCipher(Cipher.DECRYPT_MODE, cipher);
}
}
}