improvement: fix issue 1968 and correct visitor pattern code and test. (#2023)

* fix issue 1968 and correct visitor pattern code and test.

* fix README code as well.

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

@@ -33,9 +33,13 @@ public class Commander extends Unit {
     super(children);
   }
 
+  /**
+   * Accept a Visitor.
+   * @param visitor UnitVisitor to be accepted
+   */
   @Override
   public void accept(UnitVisitor visitor) {
-    visitor.visitCommander(this);
+    visitor.visit(this);
     super.accept(visitor);
   }
 

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

@@ -32,18 +32,30 @@ import lombok.extern.slf4j.Slf4j;
 @Slf4j
 public class CommanderVisitor implements UnitVisitor {
 
+  /**
+   * Soldier Visitor method.
+   * @param soldier Soldier to be visited
+   */
   @Override
-  public void visitSoldier(Soldier soldier) {
+  public void visit(Soldier soldier) {
     // Do nothing
   }
 
+  /**
+   * Sergeant Visitor method.
+   * @param sergeant Sergeant to be visited
+   */
   @Override
-  public void visitSergeant(Sergeant sergeant) {
+  public void visit(Sergeant sergeant) {
     // Do nothing
   }
 
+  /**
+   * Commander Visitor method.
+   * @param commander Commander to be visited
+   */
   @Override
-  public void visitCommander(Commander commander) {
+  public void visit(Commander commander) {
     LOGGER.info("Good to see you {}", commander);
   }
 }

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

@@ -33,9 +33,13 @@ public class Sergeant extends Unit {
     super(children);
   }
 
+  /**
+   * Accept a Visitor.
+   * @param visitor UnitVisitor to be accepted
+   */
   @Override
   public void accept(UnitVisitor visitor) {
-    visitor.visitSergeant(this);
+    visitor.visit(this);
     super.accept(visitor);
   }
 

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

@@ -32,18 +32,30 @@ import lombok.extern.slf4j.Slf4j;
 @Slf4j
 public class SergeantVisitor implements UnitVisitor {
 
+  /**
+   * Soldier Visitor method.
+   * @param soldier Soldier to be visited
+   */
   @Override
-  public void visitSoldier(Soldier soldier) {
+  public void visit(Soldier soldier) {
     // Do nothing
   }
 
+  /**
+   * Sergeant Visitor method.
+   * @param sergeant Sergeant to be visited
+   */
   @Override
-  public void visitSergeant(Sergeant sergeant) {
+  public void visit(Sergeant sergeant) {
     LOGGER.info("Hello {}", sergeant);
   }
 
+  /**
+   * Commander Visitor method.
+   * @param commander Commander to be visited
+   */
   @Override
-  public void visitCommander(Commander commander) {
+  public void visit(Commander commander) {
     // Do nothing
   }
 }

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

@@ -33,9 +33,13 @@ public class Soldier extends Unit {
     super(children);
   }
 
+  /**
+   * Accept a Visitor.
+   * @param visitor UnitVisitor to be accepted
+   */
   @Override
   public void accept(UnitVisitor visitor) {
-    visitor.visitSoldier(this);
+    visitor.visit(this);
     super.accept(visitor);
   }
 

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

@@ -32,18 +32,30 @@ import lombok.extern.slf4j.Slf4j;
 @Slf4j
 public class SoldierVisitor implements UnitVisitor {
 
+  /**
+   * Soldier Visitor method.
+   * @param soldier Soldier to be visited
+   */
   @Override
-  public void visitSoldier(Soldier soldier) {
+  public void visit(Soldier soldier) {
     LOGGER.info("Greetings {}", soldier);
   }
 
+  /**
+   * Sergeant Visitor method.
+   * @param sergeant Sergeant to be visited
+   */
   @Override
-  public void visitSergeant(Sergeant sergeant) {
+  public void visit(Sergeant sergeant) {
     // Do nothing
   }
 
+  /**
+   * Commander Visitor method.
+   * @param commander Commander to be visited
+   */
   @Override
-  public void visitCommander(Commander commander) {
+  public void visit(Commander commander) {
     // Do nothing
   }
 }

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

@@ -29,10 +29,10 @@ package com.iluwatar.visitor;
  */
 public interface UnitVisitor {
 
-  void visitSoldier(Soldier soldier);
+  void visit(Soldier soldier);
 
-  void visitSergeant(Sergeant sergeant);
+  void visit(Sergeant sergeant);
 
-  void visitCommander(Commander commander);
+  void visit(Commander commander);
 
 }

visitor/src/test/java/com/iluwatar/visitor/CommanderTest.java

@@ -43,7 +43,7 @@ public class CommanderTest extends UnitTest<Commander> {
 
   @Override
   void verifyVisit(Commander unit, UnitVisitor mockedVisitor) {
-    verify(mockedVisitor).visitCommander(eq(unit));
+    verify(mockedVisitor).visit(eq(unit));
   }
 
 }

visitor/src/test/java/com/iluwatar/visitor/SergeantTest.java

@@ -43,7 +43,7 @@ public class SergeantTest extends UnitTest<Sergeant> {
 
   @Override
   void verifyVisit(Sergeant unit, UnitVisitor mockedVisitor) {
-    verify(mockedVisitor).visitSergeant(eq(unit));
+    verify(mockedVisitor).visit(eq(unit));
   }
 
 }

visitor/src/test/java/com/iluwatar/visitor/SoldierTest.java

@@ -43,7 +43,7 @@ public class SoldierTest extends UnitTest<Soldier> {
 
   @Override
   void verifyVisit(Soldier unit, UnitVisitor mockedVisitor) {
-    verify(mockedVisitor).visitSoldier(eq(unit));
+    verify(mockedVisitor).visit(eq(unit));
   }
 
 }

visitor/src/test/java/com/iluwatar/visitor/VisitorTest.java

@@ -98,7 +98,7 @@ public abstract class VisitorTest<V extends UnitVisitor> {
 
   @Test
   void testVisitCommander() {
-    this.visitor.visitCommander(new Commander());
+    this.visitor.visit(new Commander());
     if (this.commanderResponse.isPresent()) {
       assertEquals(this.commanderResponse.get(), appender.getLastMessage());
       assertEquals(1, appender.getLogSize());
@@ -107,7 +107,7 @@ public abstract class VisitorTest<V extends UnitVisitor> {
 
   @Test
   void testVisitSergeant() {
-    this.visitor.visitSergeant(new Sergeant());
+    this.visitor.visit(new Sergeant());
     if (this.sergeantResponse.isPresent()) {
       assertEquals(this.sergeantResponse.get(), appender.getLastMessage());
       assertEquals(1, appender.getLogSize());
@@ -116,7 +116,7 @@ public abstract class VisitorTest<V extends UnitVisitor> {
 
   @Test
   void testVisitSoldier() {
-    this.visitor.visitSoldier(new Soldier());
+    this.visitor.visit(new Soldier());
     if (this.soldierResponse.isPresent()) {
       assertEquals(this.soldierResponse.get(), appender.getLastMessage());
       assertEquals(1, appender.getLogSize());