Remove trailing whitespace

- Let Checkstyle check for trailing whitespace
- Use final

src/conf/checkstyle/checkstyle.xml

@@ -46,11 +46,16 @@ limitations under the License.
       <property name="separated" value="true" />
     </module>
   </module>
-  <!-- @author tags are deprecated -->
   <module name="RegexpSingleline">
+    <!-- @author tags are deprecated -->
     <property name="format" value="^\s+\*\s+@author\s" />
     <property name="message" value="Deprecated @author tag" />
     <property name="fileExtensions" value="java" />
     <property name="severity" value="warning" />
   </module>
+  <module name="RegexpSingleline">
+    <!-- \s matches whitespace character, $ matches end of line. -->
+    <property name="format" value="\s+$" />
+    <property name="message" value="Line has trailing spaces." />
+  </module>
 </module>

src/main/java/org/apache/commons/crypto/Crypto.java

@@ -108,7 +108,7 @@ private static Properties getComponentProperties() {
     public static final String JNA_LIBRARY_NAME_DEFAULT = "crypto";
     /**
      * Name for loading SSL crypto library using dlopen on macOS
-     * JNA automatically adds prefix and suffix; dlopen does not 
+     * JNA automatically adds prefix and suffix; dlopen does not
      */
     public static final String MACOS_LIBRARY_NAME_DEFAULT = "libcrypto.dylib";
 
@@ -201,7 +201,7 @@ public static void main(final String[] args) throws Exception {
             info("DLL path: %s", OpenSslInfoNative.DLLPath());
             info("Additional OpenSSL_version(n) details:");
             for (int j = 1; j < Utils.OPENSSL_VERSION_MAX_INDEX; j++) { // entry 0 is shown above
-                String data = OpenSslInfoNative.OpenSSLVersion(j);
+                final String data = OpenSslInfoNative.OpenSSLVersion(j);
                 if (!"not available".equals(data)) {
                     info("OpenSSLVersion(%d): %s", j, data);
                 }
@@ -212,7 +212,7 @@ public static void main(final String[] args) throws Exception {
                 try (CryptoRandom cryptoRandom = CryptoRandomFactory.getCryptoRandom(props)) {
                     info("Random instance created OK: %s", cryptoRandom);
                 }
-            } catch (Exception e) {
+            } catch (final Exception e) {
                 info("Failed: %s", e);
             }
             try { // CryptoCipher
@@ -221,11 +221,11 @@ public static void main(final String[] args) throws Exception {
                 try (CryptoCipher cryptoCipher = CryptoCipherFactory.getCryptoCipher(AES.CTR_NO_PADDING, props)) {
                     info("Cipher %s instance created OK: %s", AES.CTR_NO_PADDING, cryptoCipher);
                 }
-            } catch (Exception e) {
+            } catch (final Exception e) {
                 info("Failed: %s", e);
             }
         } else {
-            Throwable error = getLoadingError();
+            final Throwable error = getLoadingError();
             String msg = "";
             if (error != null) {
                 msg = error.getMessage();

src/main/java/org/apache/commons/crypto/jna/OpenSslJna.java

@@ -108,7 +108,7 @@ public static void main(final String[] args) throws Throwable {
         }
         info("OpenSSL library loaded OK, version: 0x%s", Long.toHexString(OpenSslNativeJna.OpenSSL_version_num()));
         for (int i = 0; i <= Utils.OPENSSL_VERSION_MAX_INDEX; i++) {
-            String data = OpenSslNativeJna.OpenSSLVersion(i);
+            final String data = OpenSslNativeJna.OpenSSLVersion(i);
             if (!"not available".equals(data)) {
                 info("OpenSSLVersion(%d): %s", i, data);
             }

src/main/java/org/apache/commons/crypto/jna/OpenSslMacOS.java

@@ -45,9 +45,9 @@ class OpenSslMacOS {
      * @param path
      * @return null if OK, else error message
      */
-    public static String checkLibrary(String path) {
-        boolean loadedOK = dlopen_preflight(path) != 0;
-        String dlerror = dlerror(); // fetch error, and clear for next call
+    public static String checkLibrary(final String path) {
+        final boolean loadedOK = dlopen_preflight(path) != 0;
+        final String dlerror = dlerror(); // fetch error, and clear for next call
         return  loadedOK ? null : dlerror;
     }
 

src/main/java/org/apache/commons/crypto/jna/OpenSslNativeJna.java

@@ -61,7 +61,7 @@ final class OpenSslNativeJna {
             && System.getProperty(Crypto.JNA_LIBRARY_NAME_PROPERTY, "").isEmpty()
             && System.getProperty(Crypto.JNA_LIBRARY_PATH_PROPERTY, "").isEmpty()
         ) {
-            String ret = OpenSslMacOS.checkLibrary(Crypto.MACOS_LIBRARY_NAME_DEFAULT);
+            final String ret = OpenSslMacOS.checkLibrary(Crypto.MACOS_LIBRARY_NAME_DEFAULT);
             if (ret != null) {
                 throw new UnsatisfiedLinkError(
                     String.format("Cannot load default library '%s'; please define %s! (%s)",

src/main/java/org/apache/commons/crypto/stream/PositionedCryptoInputStream.java

@@ -149,7 +149,7 @@ private void cleanCipherStatePool() {
         while ((cs = cipherStatePool.poll()) != null) {
             try {
                 cs.getCryptoCipher().close();
-            } catch (IOException ignored) {
+            } catch (final IOException ignored) {
                 // ignore
             }
         }

src/main/java/org/apache/commons/crypto/utils/Utils.java

@@ -211,7 +211,7 @@ public static Properties getProperties(final Properties newProp) {
      * However on Windows, all the DLL versions seem to be stored in the same directory.
      * This means that Windows code needs to be given the versioned name (e.g. libcrypto-1_1-x64)
      * This is done by defining Crypto.JNI_LIBRARY_NAME.
-     * 
+     *
      * Do not change the method name or its signature!
      */
     static String libraryPath(final String name) {

src/test/java/org/apache/commons/crypto/cipher/AbstractCipherTest.java

@@ -59,7 +59,7 @@ public abstract class AbstractCipherTest {
 	private Properties props;
 
 	protected String cipherClass;
-	protected String[] transformations = new String[] {
+	protected String[] transformations = {
 		AES.CBC_NO_PADDING,
 		AES.CBC_PKCS5_PADDING,
 		AES.CTR_NO_PADDING,

src/test/java/org/apache/commons/crypto/random/CryptoRandomFactoryTest.java

@@ -79,7 +79,7 @@ public void testEmpty() throws Exception {
     @Test
     public void testExceptionInInitializerErrorRandom() throws GeneralSecurityException, IOException {
         final Properties properties = new Properties();
-        String classes = ExceptionInInitializerErrorRandom.class.getName().concat(",")
+        final String classes = ExceptionInInitializerErrorRandom.class.getName().concat(",")
             .concat(CryptoRandomFactory.RandomProvider.JAVA.getClassName());
         properties.setProperty(CryptoRandomFactory.CLASSES_KEY, classes);
         // Invoke 3 times to test the reentrancy of the method in the scenario of class initialization failure.

src/test/java/org/apache/commons/crypto/random/ExceptionInInitializerErrorRandom.java

@@ -43,7 +43,7 @@ public void close() throws IOException {
     }
 
     @Override
-    public void nextBytes(byte[] bytes) {
+    public void nextBytes(final byte[] bytes) {
         // empty
     }
 }