Decryption.java

package com.freemindcafe.security.sample2;

import java.net.URLDecoder;
import java.security.Provider;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;

import org.apache.commons.codec.binary.Base64;
import org.apache.log4j.Logger;

public class Decryption {
    static Logger logger = Logger.getLogger( Decryption.class );


   
public static String decrypt( String value, String keyStorePath, String keyStoreType, String keyStorePassword, String keyAlias ) throws Exception {
        SecretKey sKey;
        Provider securityProvider = null;
        sKey = EncryptionUtil.readKeyFromKeystore(keyStorePath, keyStoreType, keyStorePassword, keyAlias);
        securityProvider = EncryptionUtil.getSupportingSecurityProvider(keyStoreType);
        return decrypt(value, sKey, securityProvider);
    }

    public static String decrypt(String encryptedText, SecretKey key, Provider securityProvider) throws Exception {
        Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding", securityProvider);
        cipher.init(Cipher.DECRYPT_MODE, key);
        String urlDecodedString = URLDecoder.decode(encryptedText, "UTF8");
        byte[] decodedValue = Base64.decodeBase64(urlDecodedString.getBytes());
        byte[] decryptedValue = cipher.doFinal(decodedValue);
        String decryptedString = new String(decryptedValue);
        return decryptedString;
    }
   
}