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package org.apache.cayenne.crypto.unit;
import java.security.Key;
import org.apache.cayenne.crypto.transformer.bytes.BytesDecryptor;
import org.apache.cayenne.crypto.transformer.bytes.BytesEncryptor;
/**
* A fake "cipher" used for unit tests that does simple bytes swapping.
*/
public class SwapBytesTransformer implements BytesEncryptor, BytesDecryptor {
private static final SwapBytesTransformer instance = new SwapBytesTransformer();
public static BytesEncryptor encryptor() {
return instance;
}
public static BytesDecryptor decryptor() {
return instance;
}
private SwapBytesTransformer() {
}
@Override
public byte[] decrypt(byte[] input, int inputOffset, Key key) {
byte[] output = new byte[input.length - inputOffset];
System.arraycopy(input, inputOffset, output, 0, input.length - inputOffset);
swap(output, 0, output.length - 1);
return output;
}
@Override
public byte[] encrypt(byte[] input, int outputOffset, byte[] flags) {
byte[] output = new byte[input.length + outputOffset];
System.arraycopy(input, 0, output, outputOffset, input.length);
swap(output, outputOffset, outputOffset + input.length - 1);
return output;
}
private void swap(byte[] buffer, int start, int end) {
if (start >= end) {
return;
}
byte b = buffer[end];
buffer[end] = buffer[start];
buffer[start] = b;
swap(buffer, ++start, --end);
}
}