remove try/catch block and add throw clause

core-java-modules/core-java-security-2/src/main/java/com/baeldung/aes/AESUtil.java

@@ -1,8 +1,5 @@
 package com.baeldung.aes;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import javax.crypto.Cipher;
 import javax.crypto.IllegalBlockSizeException;
 import javax.crypto.NoSuchPaddingException;
@@ -28,36 +25,25 @@ import java.security.spec.KeySpec;
 import java.util.Base64;
 
 public class AESUtil {
-    private static final Logger LOGGER = LoggerFactory.getLogger(AESUtil.class);
 
-    public static String encrypt(String algorithm, String input, SecretKey key, IvParameterSpec iv) {
+    public static String encrypt(String algorithm, String input, SecretKey key, IvParameterSpec iv)
-        try {
+        throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException,
+        InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
         Cipher cipher = Cipher.getInstance(algorithm);
         cipher.init(Cipher.ENCRYPT_MODE, key, iv);
         byte[] cipherText = cipher.doFinal(input.getBytes());
         return Base64.getEncoder()
             .encodeToString(cipherText);
-        } catch (NoSuchAlgorithmException | NoSuchPaddingException |
-            InvalidKeyException | InvalidAlgorithmParameterException |
-            IllegalBlockSizeException | BadPaddingException exp) {
-            LOGGER.error(exp.getMessage());
-        }
-        return null;
     }
 
-    public static String decrypt(String algorithm, String cipherText, SecretKey key, IvParameterSpec iv) {
+    public static String decrypt(String algorithm, String cipherText, SecretKey key, IvParameterSpec iv)
-        try {
+        throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException,
+        InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
         Cipher cipher = Cipher.getInstance(algorithm);
         cipher.init(Cipher.DECRYPT_MODE, key, iv);
         byte[] plainText = cipher.doFinal(Base64.getDecoder()
             .decode(cipherText));
         return new String(plainText);
-        } catch (NoSuchAlgorithmException | NoSuchPaddingException |
-            InvalidKeyException | InvalidAlgorithmParameterException |
-            IllegalBlockSizeException | BadPaddingException exp) {
-            LOGGER.error(exp.getMessage());
-        }
-        return null;
     }
 
     public static SecretKey generateKey(int n) throws NoSuchAlgorithmException {
@@ -83,14 +69,13 @@ public class AESUtil {
     }
 
     public static void encryptFile(String algorithm, SecretKey key, IvParameterSpec iv,
-        File inputFile, File outputFile) throws IOException {
+        File inputFile, File outputFile) throws IOException, NoSuchPaddingException,
-        FileInputStream inputStream = null;
+        NoSuchAlgorithmException, InvalidAlgorithmParameterException, InvalidKeyException,
-        FileOutputStream outputStream = null;
+        BadPaddingException, IllegalBlockSizeException {
-        try {
         Cipher cipher = Cipher.getInstance(algorithm);
         cipher.init(Cipher.ENCRYPT_MODE, key, iv);
-            inputStream = new FileInputStream(inputFile);
+        FileInputStream inputStream = new FileInputStream(inputFile);
-            outputStream = new FileOutputStream(outputFile);
+        FileOutputStream outputStream = new FileOutputStream(outputFile);
         byte[] buffer = new byte[64];
         int bytesRead;
         while ((bytesRead = inputStream.read(buffer)) != -1) {
@@ -103,25 +88,18 @@ public class AESUtil {
         if (outputBytes != null) {
             outputStream.write(outputBytes);
         }
-        } catch (InvalidAlgorithmParameterException | NoSuchAlgorithmException |
-            NoSuchPaddingException | BadPaddingException |
-            IllegalBlockSizeException | InvalidKeyException exp) {
-            LOGGER.error(exp.getMessage());
-        } finally {
         inputStream.close();
         outputStream.close();
     }
-    }
 
     public static void decryptFile(String algorithm, SecretKey key, IvParameterSpec iv,
-        File encryptedFile, File decryptedFile) throws IOException {
+        File encryptedFile, File decryptedFile) throws IOException, NoSuchPaddingException,
-        FileInputStream inputStream = null;
+        NoSuchAlgorithmException, InvalidAlgorithmParameterException, InvalidKeyException,
-        FileOutputStream outputStream = null;
+        BadPaddingException, IllegalBlockSizeException {
-        try {
         Cipher cipher = Cipher.getInstance(algorithm);
         cipher.init(Cipher.DECRYPT_MODE, key, iv);
-            inputStream = new FileInputStream(encryptedFile);
+        FileInputStream inputStream = new FileInputStream(encryptedFile);
-            outputStream = new FileOutputStream(decryptedFile);
+        FileOutputStream outputStream = new FileOutputStream(decryptedFile);
         byte[] buffer = new byte[64];
         int bytesRead;
         while ((bytesRead = inputStream.read(buffer)) != -1) {
@@ -134,71 +112,45 @@ public class AESUtil {
         if (output != null) {
             outputStream.write(output);
         }
-        } catch (InvalidAlgorithmParameterException | NoSuchAlgorithmException |
-            NoSuchPaddingException | BadPaddingException |
-            IllegalBlockSizeException | InvalidKeyException exp) {
-            LOGGER.error(exp.getMessage());
-        } finally {
         inputStream.close();
         outputStream.close();
     }
-    }
 
-    public static SealedObject encryptObject(String algorithm, Serializable object, SecretKey key, IvParameterSpec iv) {
+    public static SealedObject encryptObject(String algorithm, Serializable object, SecretKey key,
-        try {
+        IvParameterSpec iv) throws NoSuchPaddingException, NoSuchAlgorithmException,
+        InvalidAlgorithmParameterException, InvalidKeyException, IOException, IllegalBlockSizeException {
         Cipher cipher = Cipher.getInstance(algorithm);
         cipher.init(Cipher.ENCRYPT_MODE, key, iv);
         SealedObject sealedObject = new SealedObject(object, cipher);
         return sealedObject;
-        } catch (NoSuchAlgorithmException | NoSuchPaddingException |
-            InvalidKeyException | InvalidAlgorithmParameterException |
-            IOException | IllegalBlockSizeException exp) {
-            LOGGER.error(exp.getMessage());
-        }
-        return null;
     }
 
-    public static Serializable decryptObject(String algorithm, SealedObject sealedObject,
+    public static Serializable decryptObject(String algorithm, SealedObject sealedObject, SecretKey key,
-        SecretKey key, IvParameterSpec iv) {
+        IvParameterSpec iv) throws NoSuchPaddingException, NoSuchAlgorithmException,
-        try {
+        InvalidAlgorithmParameterException, InvalidKeyException, ClassNotFoundException,
+        BadPaddingException, IllegalBlockSizeException, IOException {
         Cipher cipher = Cipher.getInstance(algorithm);
         cipher.init(Cipher.DECRYPT_MODE, key, iv);
         Serializable unsealObject = (Serializable) sealedObject.getObject(cipher);
         return unsealObject;
-        } catch (NoSuchAlgorithmException | NoSuchPaddingException |
-            InvalidKeyException | InvalidAlgorithmParameterException |
-            IOException | ClassNotFoundException | IllegalBlockSizeException | BadPaddingException exp) {
-            LOGGER.error(exp.getMessage());
-        }
-        return null;
     }
 
-    public static String encryptPasswordBased(String plainText, SecretKey key, IvParameterSpec iv) {
+    public static String encryptPasswordBased(String plainText, SecretKey key, IvParameterSpec iv)
-        try {
+        throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException,
+        InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
         Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
         cipher.init(Cipher.ENCRYPT_MODE, key, iv);
         return Base64.getEncoder()
             .encodeToString(cipher.doFinal(plainText.getBytes()));
-        } catch (NoSuchAlgorithmException | BadPaddingException |
-            InvalidKeyException | InvalidAlgorithmParameterException |
-            NoSuchPaddingException | IllegalBlockSizeException exp) {
-            LOGGER.error(exp.getMessage());
-        }
-        return null;
     }
 
-    public static String decryptPasswordBased(String cipherText, SecretKey key, IvParameterSpec iv) {
+    public static String decryptPasswordBased(String cipherText, SecretKey key, IvParameterSpec iv)
-        try {
+        throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException,
+        InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
         Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
         cipher.init(Cipher.DECRYPT_MODE, key, iv);
         return new String(cipher.doFinal(Base64.getDecoder()
             .decode(cipherText)));
-        } catch (NoSuchAlgorithmException | BadPaddingException |
-            InvalidKeyException | InvalidAlgorithmParameterException |
-            NoSuchPaddingException | IllegalBlockSizeException exp) {
-            LOGGER.error(exp.getMessage());
-        }
-        return null;
     }
 
 }