Minor Improvement: (#700)

* Add final variable.try to make the code read-only

src/main/java/org/apache/commons/lang3/ArrayUtils.java

@@ -785,7 +785,7 @@ public static <T> T[] add(final T[] array, final int index, final T element) {
      * @throws IllegalArgumentException if both arguments are null
      */
     public static <T> T[] add(final T[] array, final T element) {
-        Class<?> type;
+        final Class<?> type;
         if (array != null) {
             type = array.getClass().getComponentType();
         } else if (element != null) {

src/main/java/org/apache/commons/lang3/ClassUtils.java

@@ -1061,7 +1061,7 @@ public static boolean isInnerClass(final Class<?> cls) {
     public static Class<?> getClass(
             final ClassLoader classLoader, final String className, final boolean initialize) throws ClassNotFoundException {
         try {
-            Class<?> clazz;
+            final Class<?> clazz;
             if (namePrimitiveMap.containsKey(className)) {
                 clazz = namePrimitiveMap.get(className);
             } else {
@@ -1173,7 +1173,7 @@ public static Method getPublicMethod(final Class<?> cls, final String methodName
             if (!Modifier.isPublic(candidateClass.getModifiers())) {
                 continue;
             }
-            Method candidateMethod;
+            final Method candidateMethod;
             try {
                 candidateMethod = candidateClass.getMethod(methodName, parameterTypes);
             } catch (final NoSuchMethodException ex) {

src/main/java/org/apache/commons/lang3/RandomStringUtils.java

@@ -399,7 +399,7 @@ public static String random(int count, int start, int end, final boolean letters
         final int gap = end - start;
 
         while (count-- != 0) {
-            int codePoint;
+            final int codePoint;
             if (chars == null) {
                 codePoint = random.nextInt(gap) + start;
 

src/main/java/org/apache/commons/lang3/StringUtils.java

@@ -4739,7 +4739,7 @@ public static String join(final Object[] array, final String delimiter) {
      * {@code endIndex < 0} or <br>
      * {@code endIndex > array.length()}
      */
-    public static String join(final Object[] array, String delimiter, final int startIndex, final int endIndex) {
+    public static String join(final Object[] array, final String delimiter, final int startIndex, final int endIndex) {
         if (array == null) {
             return null;
         }
@@ -5423,8 +5423,8 @@ public static String lowerCase(final String str, final Locale locale) {
     }
 
     private static int[] matches(final CharSequence first, final CharSequence second) {
-        CharSequence max;
+        final CharSequence max;
-        CharSequence min;
+        final CharSequence min;
         if (first.length() > second.length()) {
             max = first;
             min = second;

src/main/java/org/apache/commons/lang3/builder/DiffBuilder.java

@@ -811,7 +811,7 @@ public DiffBuilder<T> append(final String fieldName, final Object lhs,
             return this;
         }
 
-        Object objectToTest;
+        final Object objectToTest;
         if (lhs != null) {
             objectToTest = lhs;
         } else {

src/main/java/org/apache/commons/lang3/concurrent/BackgroundInitializer.java

@@ -175,7 +175,7 @@ public synchronized boolean start() {
 
             // Determine the executor to use and whether a temporary one has to
             // be created
-            ExecutorService tempExec;
+            final ExecutorService tempExec;
             executor = getExternalExecutor();
             if (executor == null) {
                 executor = tempExec = createExecutor();

src/main/java/org/apache/commons/lang3/concurrent/EventCountCircuitBreaker.java

@@ -376,7 +376,7 @@ private void changeStateAndStartNewCheckInterval(final State newState) {
      */
     private CheckIntervalData nextCheckIntervalData(final int increment,
             final CheckIntervalData currentData, final State currentState, final long time) {
-        CheckIntervalData nextData;
+        final CheckIntervalData nextData;
         if (stateStrategy(currentState).isCheckIntervalFinished(this, currentData, time)) {
             nextData = new CheckIntervalData(increment, time);
         } else {

src/main/java/org/apache/commons/lang3/concurrent/MultiBackgroundInitializer.java

@@ -176,7 +176,7 @@ protected int getTaskCount() {
      */
     @Override
     protected MultiBackgroundInitializerResults initialize() throws Exception {
-        Map<String, BackgroundInitializer<?>> inits;
+        final Map<String, BackgroundInitializer<?>> inits;
         synchronized (this) {
             // create a snapshot to operate on
             inits = new HashMap<>(

src/main/java/org/apache/commons/lang3/math/Fraction.java

@@ -178,7 +178,7 @@ public static Fraction getFraction(final int whole, final int numerator, final i
         if (numerator < 0) {
             throw new ArithmeticException("The numerator must not be negative");
         }
-        long numeratorValue;
+        final long numeratorValue;
         if (whole < 0) {
             numeratorValue = whole * (long) denominator - numerator;
         } else {

src/main/java/org/apache/commons/lang3/math/NumberUtils.java

@@ -683,9 +683,9 @@ public static Number createNumber(final String str) {
             return createInteger(str);
         }
         final char lastChar = str.charAt(length - 1);
-        String mant;
+        final String mant;
-        String dec;
+        final String dec;
-        String exp;
+        final String exp;
         final int decPos = str.indexOf('.');
         final int expPos = str.indexOf('e') + str.indexOf('E') + 1; // assumes both not present
         // if both e and E are present, this is caught by the checks on expPos (which prevent IOOBE)

src/main/java/org/apache/commons/lang3/reflect/MethodUtils.java

@@ -1021,7 +1021,7 @@ private static List<Class<?>> getAllSuperclassesAndInterfaces(final Class<?> cls
         int interfaceIndex = 0;
         while (interfaceIndex < allInterfaces.size() ||
                 superClassIndex < allSuperclasses.size()) {
-            Class<?> acls;
+            final Class<?> acls;
             if (interfaceIndex >= allInterfaces.size()) {
                 acls = allSuperclasses.get(superClassIndex++);
             } else if ((superClassIndex >= allSuperclasses.size()) || (interfaceIndex < superClassIndex) || !(superClassIndex < interfaceIndex)) {

src/main/java/org/apache/commons/lang3/reflect/TypeUtils.java

@@ -885,7 +885,7 @@ private static Map<TypeVariable<?>, Type> getTypeArguments(
         }
 
         final Type ownerType = parameterizedType.getOwnerType();
-        Map<TypeVariable<?>, Type> typeVarAssigns;
+        final Map<TypeVariable<?>, Type> typeVarAssigns;
 
         if (ownerType instanceof ParameterizedType) {
             // get the owner type arguments first

src/main/java/org/apache/commons/lang3/text/translate/NumericEntityUnescaper.java

@@ -133,7 +133,7 @@ public int translate(final CharSequence input, final int index, final Writer out
                 }
             }
 
-            int entityValue;
+            final int entityValue;
             try {
                 if (isHex) {
                     entityValue = Integer.parseInt(input.subSequence(start, end).toString(), 16);

src/main/java/org/apache/commons/lang3/time/FastDateParser.java

@@ -131,7 +131,7 @@ protected FastDateParser(final String pattern, final TimeZone timeZone, final Lo
 
         final Calendar definingCalendar = Calendar.getInstance(timeZone, this.locale);
 
-        int centuryStartYear;
+        final int centuryStartYear;
         if (centuryStart!=null) {
             definingCalendar.setTime(centuryStart);
             centuryStartYear = definingCalendar.get(Calendar.YEAR);

src/main/java/org/apache/commons/lang3/time/FormatCache.java

@@ -189,7 +189,7 @@ static String getPatternForStyle(final Integer dateStyle, final Integer timeStyl
         String pattern = cDateTimeInstanceCache.get(key);
         if (pattern == null) {
             try {
-                DateFormat formatter;
+                final DateFormat formatter;
                 if (dateStyle == null) {
                     formatter = DateFormat.getTimeInstance(timeStyle.intValue(), safeLocale);
                 } else if (timeStyle == null) {
@@ -217,7 +217,7 @@ static String getPatternForStyle(final Integer dateStyle, final Integer timeStyl
      */
     private static final class ArrayKey {
 
-        private static int computeHashCode(Object[] keys) {
+        private static int computeHashCode(final Object[] keys) {
             final int prime = 31;
             int result = 1;
             result = prime * result + Arrays.hashCode(keys);
@@ -243,7 +243,7 @@ public int hashCode() {
         }
 
         @Override
-        public boolean equals(Object obj) {
+        public boolean equals(final Object obj) {
             if (this == obj) {
                 return true;
             }
@@ -253,7 +253,7 @@ public boolean equals(Object obj) {
             if (getClass() != obj.getClass()) {
                 return false;
             }
-            ArrayKey other = (ArrayKey) obj;
+            final ArrayKey other = (ArrayKey) obj;
             return Arrays.deepEquals(keys, other.keys);
         }