Break out common code from RoShamBo1.java, reuse in patterns

enums/Item.java

@@ -0,0 +1,12 @@
+// enums/Item.java
+// (c)2021 MindView LLC: see Copyright.txt
+// We make no guarantees that this code is fit for any purpose.
+// Visit http://OnJava8.com for more book information.
+package enums;
+
+public interface Item {
+  Outcome compete(Item it);
+  Outcome eval(Paper p);
+  Outcome eval(Scissors s);
+  Outcome eval(Rock r);
+}

enums/Paper.java

@@ -0,0 +1,21 @@
+// enums/Paper.java
+// (c)2021 MindView LLC: see Copyright.txt
+// We make no guarantees that this code is fit for any purpose.
+// Visit http://OnJava8.com for more book information.
+package enums;
+import static enums.Outcome.*;
+
+public class Paper implements Item {
+  @Override public Outcome compete(Item it) {
+    return it.eval(this);
+  }
+  @Override
+  public Outcome eval(Paper p) { return DRAW; }
+  @Override
+  public Outcome eval(Scissors s) { return WIN; }
+  @Override
+  public Outcome eval(Rock r) { return LOSE; }
+  @Override public String toString() {
+    return "Paper";
+  }
+}

enums/RoShamBo1.java

@@ -6,59 +6,6 @@
 // {java enums.RoShamBo1}
 package enums;
 import java.util.*;
-import static enums.Outcome.*;
-
-interface Item {
-  Outcome compete(Item it);
-  Outcome eval(Paper p);
-  Outcome eval(Scissors s);
-  Outcome eval(Rock r);
-}
-
-class Paper implements Item {
-  @Override public Outcome compete(Item it) {
-    return it.eval(this);
-  }
-  @Override
-  public Outcome eval(Paper p) { return DRAW; }
-  @Override
-  public Outcome eval(Scissors s) { return WIN; }
-  @Override
-  public Outcome eval(Rock r) { return LOSE; }
-  @Override public String toString() {
-    return "Paper";
-  }
-}
-
-class Scissors implements Item {
-  @Override public Outcome compete(Item it) {
-    return it.eval(this);
-  }
-  @Override
-  public Outcome eval(Paper p) { return LOSE; }
-  @Override
-  public Outcome eval(Scissors s) { return DRAW; }
-  @Override
-  public Outcome eval(Rock r) { return WIN; }
-  @Override public String toString() {
-    return "Scissors";
-  }
-}
-
-class Rock implements Item {
-  @Override public Outcome compete(Item it) {
-    return it.eval(this);
-  }
-  @Override
-  public Outcome eval(Paper p) { return WIN; }
-  @Override
-  public Outcome eval(Scissors s) { return LOSE; }
-  @Override
-  public Outcome eval(Rock r) { return DRAW; }
-  @Override public String toString() {
-    return "Rock";
-  }
-}
 
 public class RoShamBo1 {
   static final int SIZE = 20;

enums/Rock.java

@@ -0,0 +1,21 @@
+// enums/Rock.java
+// (c)2021 MindView LLC: see Copyright.txt
+// We make no guarantees that this code is fit for any purpose.
+// Visit http://OnJava8.com for more book information.
+package enums;
+import static enums.Outcome.*;
+
+public class Rock implements Item {
+  @Override public Outcome compete(Item it) {
+    return it.eval(this);
+  }
+  @Override
+  public Outcome eval(Paper p) { return WIN; }
+  @Override
+  public Outcome eval(Scissors s) { return LOSE; }
+  @Override
+  public Outcome eval(Rock r) { return DRAW; }
+  @Override public String toString() {
+    return "Rock";
+  }
+}

enums/Scissors.java

@@ -0,0 +1,21 @@
+// enums/Scissors.java
+// (c)2021 MindView LLC: see Copyright.txt
+// We make no guarantees that this code is fit for any purpose.
+// Visit http://OnJava8.com for more book information.
+package enums;
+import static enums.Outcome.*;
+
+public class Scissors implements Item {
+  @Override public Outcome compete(Item it) {
+    return it.eval(this);
+  }
+  @Override
+  public Outcome eval(Paper p) { return LOSE; }
+  @Override
+  public Outcome eval(Scissors s) { return DRAW; }
+  @Override
+  public Outcome eval(Rock r) { return WIN; }
+  @Override public String toString() {
+    return "Scissors";
+  }
+}

gradle/subprojects.gradle

@@ -58,6 +58,12 @@ project(':collections') {
     }
 }
 
+project(':patterns') {
+    dependencies {
+        compile project(':enums')
+    }
+}
+
 configure(subprojects - project(':onjava')) {
     dependencies {
         compile project(':onjava')

patterns/PaperScissorsRock.java

@@ -6,72 +6,15 @@
 import java.util.*;
 import java.util.function.*;
 import java.util.stream.*;
+import enums.Outcome;
+import static enums.Outcome.*;
+import enums.Item;
+import enums.Paper;
+import enums.Scissors;
+import enums.Rock;
 import onjava.*;
 import static onjava.Tuple.*;
 
-enum Outcome { WIN, LOSE, DRAW }
-
-interface Item {
-  Outcome compete(Item it);
-  Outcome eval(Paper p);
-  Outcome eval(Scissors s);
-  Outcome eval(Rock r);
-}
-
-class Paper implements Item {
-  @Override public Outcome compete(Item it) {
-    return it.eval(this);
-  }
-  @Override public Outcome eval(Paper p) {
-    return Outcome.DRAW;
-  }
-  @Override public Outcome eval(Scissors s) {
-    return Outcome.WIN;
-  }
-  @Override public Outcome eval(Rock r) {
-    return Outcome.LOSE;
-  }
-  @Override public String toString() {
-    return "Paper";
-  }
-}
-
-class Scissors implements Item {
-  @Override public Outcome compete(Item it) {
-    return it.eval(this);
-  }
-  @Override public Outcome eval(Paper p) {
-    return Outcome.LOSE;
-  }
-  @Override public Outcome eval(Scissors s) {
-    return Outcome.DRAW;
-  }
-  @Override public Outcome eval(Rock r) {
-    return Outcome.WIN;
-  }
-  @Override public String toString() {
-    return "Scissors";
-  }
-}
-
-class Rock implements Item {
-  @Override public Outcome compete(Item it) {
-    return it.eval(this);
-  }
-  @Override public Outcome eval(Paper p) {
-    return Outcome.WIN;
-  }
-  @Override public Outcome eval(Scissors s) {
-    return Outcome.LOSE;
-  }
-  @Override public Outcome eval(Rock r) {
-    return Outcome.DRAW;
-  }
-  @Override public String toString() {
-    return "Rock";
-  }
-}
-
 class ItemFactory {
   static List<Supplier<Item>> items =
     Arrays.asList(