Improved comments on visitor pattern example.

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

@@ -2,10 +2,15 @@ package com.iluwatar;
 
 /**
  * 
- * Visitor pattern defines mechanism to apply operations (UnitVisitor) on nodes
+ * Visitor pattern defines mechanism to apply operations on nodes
- * (Unit) in hierarchy. New operations can be added without altering the node
+ * in hierarchy. New operations can be added without altering the node
  * interface.
  * 
+ * In this example there is a unit hierarchy beginning from Commander.
+ * This hierarchy is traversed by visitors. SoldierVisitor applies
+ * its operation on Soldiers, SergeantVisitor on Sergeants and so
+ * on.
+ * 
  */
 public class App {
 

visitor/src/main/java/com/iluwatar/Commander.java

@@ -1,5 +1,10 @@
 package com.iluwatar;
 
+/**
+ * 
+ * Commander
+ *
+ */
 public class Commander extends Unit {
 
 	public Commander(Unit... children) {

visitor/src/main/java/com/iluwatar/CommanderVisitor.java

@@ -1,5 +1,10 @@
 package com.iluwatar;
 
+/**
+ * 
+ * CommanderVisitor
+ *
+ */
 public class CommanderVisitor implements UnitVisitor {
 
 	@Override

visitor/src/main/java/com/iluwatar/Sergeant.java

@@ -1,5 +1,10 @@
 package com.iluwatar;
 
+/**
+ * 
+ * Sergeant
+ *
+ */
 public class Sergeant extends Unit {
 
 	public Sergeant(Unit... children) {

visitor/src/main/java/com/iluwatar/SergeantVisitor.java

@@ -1,5 +1,10 @@
 package com.iluwatar;
 
+/**
+ * 
+ * SergeantVisitor
+ *
+ */
 public class SergeantVisitor implements UnitVisitor {
 
 	@Override

visitor/src/main/java/com/iluwatar/Soldier.java

@@ -1,5 +1,10 @@
 package com.iluwatar;
 
+/**
+ * 
+ * Soldier
+ *
+ */
 public class Soldier extends Unit {
 
 	public Soldier(Unit... children) {

visitor/src/main/java/com/iluwatar/SoldierVisitor.java

@@ -1,5 +1,10 @@
 package com.iluwatar;
 
+/**
+ * 
+ * SoldierVisitor
+ *
+ */
 public class SoldierVisitor implements UnitVisitor {
 
 	@Override