Added tests for private-class-data pattern

private-class-data/pom.xml

@@ -14,5 +14,10 @@
       <artifactId>junit</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.mockito</groupId>
+      <artifactId>mockito-core</artifactId>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 </project>

private-class-data/src/test/java/com/iluwatar/privateclassdata/ImmutableStewTest.java

@@ -0,0 +1,52 @@
+package com.iluwatar.privateclassdata;
+
+import org.junit.Test;
+import org.mockito.InOrder;
+
+import static org.mockito.Mockito.inOrder;
+import static org.mockito.Mockito.verify;
+
+/**
+ * Date: 12/27/15 - 10:46 PM
+ *
+ * @author Jeroen Meulemeester
+ */
+public class ImmutableStewTest extends StdOutTest {
+
+  /**
+   * Verify if mixing the stew doesn't change the internal state
+   */
+  @Test
+  public void testMix() {
+    final Stew stew = new Stew(1, 2, 3, 4);
+    final String message = "Mixing the stew we find: 1 potatoes, 2 carrots, 3 meat and 4 peppers";
+
+    final InOrder inOrder = inOrder(getStdOutMock());
+    for (int i = 0; i < 20; i++) {
+      stew.mix();
+      inOrder.verify(getStdOutMock()).println(message);
+    }
+
+    inOrder.verifyNoMoreInteractions();
+  }
+
+  /**
+   * Verify if tasting the stew actually removes one of each ingredient
+   */
+  @Test
+  public void testDrink() {
+    final Stew stew = new Stew(1, 2, 3, 4);
+    stew.mix();
+
+    verify(getStdOutMock())
+            .println("Mixing the stew we find: 1 potatoes, 2 carrots, 3 meat and 4 peppers");
+
+    stew.taste();
+    verify(getStdOutMock()).println("Tasting the stew");
+
+    stew.mix();
+    verify(getStdOutMock())
+            .println("Mixing the stew we find: 0 potatoes, 1 carrots, 2 meat and 3 peppers");
+
+  }
+}

private-class-data/src/test/java/com/iluwatar/privateclassdata/StdOutTest.java

@@ -0,0 +1,53 @@
+package com.iluwatar.privateclassdata;
+
+import org.junit.After;
+import org.junit.Before;
+
+import java.io.PrintStream;
+
+import static org.mockito.Mockito.mock;
+
+/**
+ * Date: 12/10/15 - 8:37 PM
+ *
+ * @author Jeroen Meulemeester
+ */
+public abstract class StdOutTest {
+
+  /**
+   * The mocked standard out {@link PrintStream}, required since some actions don't have any
+   * influence on accessible objects, except for writing to std-out using {@link System#out}
+   */
+  private final PrintStream stdOutMock = mock(PrintStream.class);
+
+  /**
+   * Keep the original std-out so it can be restored after the test
+   */
+  private final PrintStream stdOutOrig = System.out;
+
+  /**
+   * Inject the mocked std-out {@link PrintStream} into the {@link System} class before each test
+   */
+  @Before
+  public void setUp() {
+    System.setOut(this.stdOutMock);
+  }
+
+  /**
+   * Removed the mocked std-out {@link PrintStream} again from the {@link System} class
+   */
+  @After
+  public void tearDown() {
+    System.setOut(this.stdOutOrig);
+  }
+
+  /**
+   * Get the mocked stdOut {@link PrintStream}
+   *
+   * @return The stdOut print stream mock, renewed before each test
+   */
+  final PrintStream getStdOutMock() {
+    return this.stdOutMock;
+  }
+
+}

private-class-data/src/test/java/com/iluwatar/privateclassdata/StewTest.java

@@ -0,0 +1,33 @@
+package com.iluwatar.privateclassdata;
+
+import org.junit.Test;
+import org.mockito.InOrder;
+
+import static org.mockito.Mockito.inOrder;
+
+/**
+ * Date: 12/27/15 - 10:46 PM
+ *
+ * @author Jeroen Meulemeester
+ */
+public class StewTest extends StdOutTest {
+
+  /**
+   * Verify if mixing the stew doesn't change the internal state
+   */
+  @Test
+  public void testMix() {
+    final ImmutableStew stew = new ImmutableStew(1, 2, 3, 4);
+    final String expectedMessage = "Mixing the immutable stew we find: 1 potatoes, " +
+            "2 carrots, 3 meat and 4 peppers";
+
+    final InOrder inOrder = inOrder(getStdOutMock());
+    for (int i = 0; i < 20; i++) {
+      stew.mix();
+      inOrder.verify(getStdOutMock()).println(expectedMessage);
+    }
+
+    inOrder.verifyNoMoreInteractions();
+  }
+
+}