Adjust checkstyle rules. Make checkstyle fail the build when violations are found. Correct all current checkstyle violations.

intercepting-filter/src/main/java/com/iluwatar/intercepting/filter/AddressFilter.java

@@ -14,7 +14,8 @@ public class AddressFilter extends AbstractFilter {
     String result = super.execute(order);
     if (order.getAddress() == null || order.getAddress().isEmpty()) {
       return result + "Invalid address! ";
-    } else
+    } else {
       return result;
+    }
   }
 }

intercepting-filter/src/main/java/com/iluwatar/intercepting/filter/Client.java

@@ -32,8 +32,12 @@ public class Client extends JFrame {
   private JLabel jl;
   private JTextField[] jtFields;
   private JTextArea[] jtAreas;
-  private JButton clearButton, processButton;
+  private JButton clearButton;
+  private JButton processButton;
 
+  /**
+   * Constructor
+   */
   public Client() {
     super("Client System");
     setDefaultCloseOperation(EXIT_ON_CLOSE);

intercepting-filter/src/main/java/com/iluwatar/intercepting/filter/Filter.java

@@ -11,30 +11,21 @@ public interface Filter {
 
   /**
    * Execute order processing filter.
-   * 
-   * @param order
-   * @return empty string on success, otherwise error message.
    */
   String execute(Order order);
 
   /**
    * Set next filter in chain after this.
-   * 
-   * @param filter
    */
   void setNext(Filter filter);
 
   /**
    * Get next filter in chain after this.
-   * 
-   * @return
    */
   Filter getNext();
 
   /**
    * Get last filter in the chain.
-   * 
-   * @return
    */
   Filter getLast();
 }

intercepting-filter/src/main/java/com/iluwatar/intercepting/filter/FilterChain.java

@@ -12,10 +12,16 @@ public class FilterChain {
 
   private final Target target;
 
+  /**
+   * Constructor
+   */
   public FilterChain(Target target) {
     this.target = target;
   }
 
+  /**
+   * Adds filter
+   */
   public void addFilter(Filter filter) {
     if (chain == null) {
       chain = filter;
@@ -24,6 +30,9 @@ public class FilterChain {
     }
   }
 
+  /**
+   * Execute filter chain
+   */
   public String execute(Order order) {
     if (chain != null) {
       return chain.execute(order);

intercepting-filter/src/main/java/com/iluwatar/intercepting/filter/Order.java

@@ -14,6 +14,9 @@ public class Order {
 
   public Order() {}
 
+  /**
+   * Constructor
+   */
   public Order(String name, String contactNumber, String address, String depositNumber, String order) {
     this.name = name;
     this.contactNumber = contactNumber;

intercepting-filter/src/main/java/com/iluwatar/intercepting/filter/Target.java

@@ -29,6 +29,9 @@ public class Target extends JFrame {
   private DefaultTableModel dtm;
   private JButton del;
 
+  /**
+   * Constructor
+   */
   public Target() {
     super("Order System");
     setDefaultCloseOperation(EXIT_ON_CLOSE);
@@ -67,8 +70,9 @@ public class Target extends JFrame {
     @Override
     public void actionPerformed(ActionEvent e) {
       int temp = jt.getSelectedRow();
-      if (temp == -1)
+      if (temp == -1) {
         return;
+      }
       int temp2 = jt.getSelectedRowCount();
       for (int i = 0; i < temp2; i++) {
         dtm.removeRow(temp);

intercepting-filter/src/test/java/com/iluwatar/intercepting/filter/FilterTest.java

@@ -73,6 +73,9 @@ public class FilterTest {
   private final Order order;
   private final String result;
 
+  /**
+   * Constructor
+   */
   public FilterTest(Filter filter, Order order, String result) {
     this.filter = filter;
     this.order = order;