Resolves checkstyle errors for intercepting-filter, interpreter, iterator (#1065)

* Reduces checkstyle errors in intercepting-filter

* Reduces checkstyle errors in interpreter

* Reduces checkstyle errors in iterator

interpreter/src/main/java/com/iluwatar/interpreter/App.java

@@ -23,35 +23,30 @@
 
 package com.iluwatar.interpreter;
 
+import java.util.Stack;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.util.Stack;
-
 /**
- * 
  * The Interpreter pattern is a design pattern that specifies how to evaluate sentences in a
  * language. The basic idea is to have a class for each symbol (terminal or nonterminal) in a
  * specialized computer language. The syntax tree of a sentence in the language is an instance of
  * the composite pattern and is used to evaluate (interpret) the sentence for a client.
- * <p>
- * In this example we use the Interpreter pattern to break sentences into expressions (
- * {@link Expression}) that can be evaluated and as a whole form the result.
- * 
+ *
+ * <p>In this example we use the Interpreter pattern to break sentences into expressions ({@link
+ * Expression}) that can be evaluated and as a whole form the result.
  */
 public class App {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
 
   /**
-   * 
    * Program entry point.
-   * <p>
-   * Expressions can be evaluated using prefix, infix or postfix notations This sample uses postfix,
-   * where operator comes after the operands
-   * 
+   *
+   * <p>Expressions can be evaluated using prefix, infix or postfix notations This sample uses
+   * postfix, where operator comes after the operands.
+   *
    * @param args command line args
-   * 
    */
   public static void main(String[] args) {
     String tokenString = "4 3 2 - 1 + *";
@@ -84,7 +79,7 @@ public class App {
   }
 
   /**
-   * Get expression for string
+   * Get expression for string.
    */
   public static Expression getOperatorInstance(String s, Expression left, Expression right) {
     switch (s) {

interpreter/src/main/java/com/iluwatar/interpreter/Expression.java

@@ -24,9 +24,7 @@
 package com.iluwatar.interpreter;
 
 /**
- * 
- * Expression
- *
+ * Expression.
  */
 public abstract class Expression {
 

interpreter/src/main/java/com/iluwatar/interpreter/MinusExpression.java

@@ -24,9 +24,7 @@
 package com.iluwatar.interpreter;
 
 /**
- * 
- * MinusExpression
- *
+ * MinusExpression.
  */
 public class MinusExpression extends Expression {
 

interpreter/src/main/java/com/iluwatar/interpreter/MultiplyExpression.java

@@ -24,9 +24,7 @@
 package com.iluwatar.interpreter;
 
 /**
- * 
- * MultiplyExpression
- *
+ * MultiplyExpression.
  */
 public class MultiplyExpression extends Expression {
 

interpreter/src/main/java/com/iluwatar/interpreter/NumberExpression.java

@@ -24,9 +24,7 @@
 package com.iluwatar.interpreter;
 
 /**
- * 
- * NumberExpression
- *
+ * NumberExpression.
  */
 public class NumberExpression extends Expression {
 

interpreter/src/main/java/com/iluwatar/interpreter/PlusExpression.java

@@ -24,9 +24,7 @@
 package com.iluwatar.interpreter;
 
 /**
- * 
- * PlusExpression
- *
+ * PlusExpression.
  */
 public class PlusExpression extends Expression {