AES Encryption Singleton Class in Android Using CBC / PKCS7Padding

android_aes_encrpytor.java

import java.io.UnsupportedEncodingException;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

import android.util.Base64;

public class CryptoHandler {

  private static CryptoHandler instance = null;
	private static byte[] KEY;
  // Your IV Initialization Vector
	private final static byte[] ivx = Globals.AES_IVX;

	protected CryptoHandler() {

		try {
      //Your Secret Key
			KEY = Globals.AES_SECRET_KEY.getBytes("UTF8");
		} catch (UnsupportedEncodingException e) {

			e.printStackTrace();
		}
	}

	public static CryptoHandler getInstance() {

		if (instance == null) {
			instance = new CryptoHandler();
		}
		return instance;
	}

	public String encrypt(String message) throws NoSuchAlgorithmException,
			NoSuchPaddingException, IllegalBlockSizeException,
			BadPaddingException, InvalidKeyException,
			UnsupportedEncodingException, InvalidAlgorithmParameterException {

		byte[] srcBuff = message.getBytes("UTF8");

		SecretKeySpec skeySpec = new SecretKeySpec(KEY, "AES");
		IvParameterSpec ivSpec = new IvParameterSpec(ivx);
		Cipher ecipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
		ecipher.init(Cipher.ENCRYPT_MODE, skeySpec, ivSpec);

		byte[] dstBuff = ecipher.doFinal(srcBuff);

		String base64 = Base64.encodeToString(dstBuff, Base64.DEFAULT);

		return base64;

	}

	public String decrypt(String encrypted) throws NoSuchAlgorithmException,
			NoSuchPaddingException, InvalidKeyException,
			InvalidAlgorithmParameterException, IllegalBlockSizeException,
			BadPaddingException, UnsupportedEncodingException {

		SecretKeySpec skeySpec = new SecretKeySpec(KEY, "AES");
		IvParameterSpec ivSpec = new IvParameterSpec(ivx);

		Cipher ecipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
		ecipher.init(Cipher.DECRYPT_MODE, skeySpec, ivSpec);

		byte[] raw = Base64.decode(encrypted, Base64.DEFAULT);

		byte[] originalBytes = ecipher.doFinal(raw);

		String original = new String(originalBytes, "UTF8");
		
		return original;

	}
}