Basic Symmetric Encryption

package io.syntx.examples.security;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.sql.SQLException;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
import org.apache.commons.codec.binary.Base64;
public class SymmetricEncryptionUtility {
public final static Key generateKey() throws NoSuchAlgorithmException{
KeyGenerator kg = KeyGenerator.getInstance("AES");
SecureRandom random = new SecureRandom();
kg.init(random);
return kg.generateKey();
}
public static final String encrypt(final String message, final Key key, final IvParameterSpec iv) throws IllegalBlockSizeException,
BadPaddingException, NoSuchAlgorithmException,
NoSuchPaddingException, InvalidKeyException,
UnsupportedEncodingException, InvalidAlgorithmParameterException {
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE,key,iv);
byte[] stringBytes = message.getBytes();
byte[] raw = cipher.doFinal(stringBytes);
return Base64.encodeBase64String(raw);
}
public static final String decrypt(final String encrypted,final Key key, final IvParameterSpec iv) throws InvalidKeyException,
NoSuchAlgorithmException, NoSuchPaddingException,
IllegalBlockSizeException, BadPaddingException, IOException, InvalidAlgorithmParameterException {
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, key,iv);
byte[] raw = Base64.decodeBase64(encrypted);
byte[] stringBytes = cipher.doFinal(raw);
String clearText = new String(stringBytes, "UTF8");
return clearText;
}
public static void main(String[] args) throws Exception{
Key k = SymmetricEncryptionUtility.generateKey();
SecureRandom random = new SecureRandom();
IvParameterSpec iv = new IvParameterSpec(random.generateSeed(16));
String clearText = "hello world";
System.out.println("Clear Text:" + clearText);
String encryptedString = SymmetricEncryptionUtility.encrypt(clearText,k,iv);
System.out.println("Encrypted String:" + encryptedString);
System.out.println("Decrypted String:"+SymmetricEncryptionUtility.decrypt(encryptedString,k,iv));
}
}

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Basic Symmetric Encryption

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