TDD section (not great yet, but runs)

verifying/StringInverter.java

@@ -0,0 +1,8 @@
+// verifying/StringInverter.java
+// (c)2016 MindView LLC: see Copyright.txt
+// We make no guarantees that this code is fit for any purpose.
+// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
+
+interface StringInverter {
+  public String invert(String str);
+}

verifying/StringInverter1.java

@@ -0,0 +1,21 @@
+// verifying/StringInverter1.java
+// (c)2016 MindView LLC: see Copyright.txt
+// We make no guarantees that this code is fit for any purpose.
+// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
+// {java StringInverterTest StringInverter1}
+
+public class StringInverter1 implements StringInverter {
+  public String invert(String str) { return ""; }
+}
+/* Output:
+StringInverter1 has 3 FAILURES:
+Failure 1:
+allowedCharacters_Fail(StringInverterTest)
+Expected exception: java.lang.RuntimeException
+Failure 2:
+basicInversion_Succeed(StringInverterTest)
+expected:<[]> but was:<[eXIT, pURSUED BY A bEAR.]>
+Failure 3:
+lengthLessThan26_Fail(StringInverterTest)
+Expected exception: java.lang.RuntimeException
+*/

verifying/StringInverter2.java

@@ -0,0 +1,28 @@
+// verifying/StringInverter2.java
+// (c)2016 MindView LLC: see Copyright.txt
+// We make no guarantees that this code is fit for any purpose.
+// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
+// {java StringInverterTest StringInverter2}
+import static java.lang.Character.*;
+
+public class StringInverter2 implements StringInverter {
+  public String invert(String str) {
+    String result = "";
+    for(int i = 0; i < str.length(); i++) {
+      char c = str.charAt(i);
+      result += isUpperCase(c) ?
+                toLowerCase(c) :
+                toUpperCase(c);
+    }
+    return result;
+  }
+}
+/* Output:
+StringInverter2 has 2 FAILURES:
+Failure 1:
+allowedCharacters_Fail(StringInverterTest)
+Expected exception: java.lang.RuntimeException
+Failure 2:
+lengthLessThan26_Fail(StringInverterTest)
+Expected exception: java.lang.RuntimeException
+*/

verifying/StringInverter3.java

@@ -0,0 +1,27 @@
+// verifying/StringInverter3.java
+// (c)2016 MindView LLC: see Copyright.txt
+// We make no guarantees that this code is fit for any purpose.
+// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
+// {java StringInverterTest StringInverter3}
+import static java.lang.Character.*;
+
+public class StringInverter3 implements StringInverter {
+  public String invert(String str) {
+    if(str.length() > 25)
+      throw new RuntimeException("argument too long!");
+    String result = "";
+    for(int i = 0; i < str.length(); i++) {
+      char c = str.charAt(i);
+      result += isUpperCase(c) ?
+                toLowerCase(c) :
+                toUpperCase(c);
+    }
+    return result;
+  }
+}
+/* Output:
+StringInverter3 has 1 FAILURES:
+Failure 1:
+allowedCharacters_Fail(StringInverterTest)
+Expected exception: java.lang.RuntimeException
+*/

verifying/StringInverter4.java

@@ -0,0 +1,29 @@
+// verifying/StringInverter4.java
+// (c)2016 MindView LLC: see Copyright.txt
+// We make no guarantees that this code is fit for any purpose.
+// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
+// {java StringInverterTest StringInverter4}
+import static java.lang.Character.*;
+
+public class StringInverter4 implements StringInverter {
+  static final String allowed =
+    "abcdefghijklmnopqrstuvwxyz ,." +
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+  public String invert(String str) {
+    if(str.length() > 25)
+      throw new RuntimeException("argument too long!");
+    String result = "";
+    for(int i = 0; i < str.length(); i++) {
+      char c = str.charAt(i);
+      if(allowed.indexOf(c) == -1)
+        throw new RuntimeException(c + " Not allowed");
+      result += isUpperCase(c) ?
+                toLowerCase(c) :
+                toUpperCase(c);
+    }
+    return result;
+  }
+}
+/* Output:
+StringInverter4 has 0 FAILURES:
+*/

verifying/StringInverterTest.java

@@ -0,0 +1,64 @@
+// verifying/StringInverterTest.java
+// (c)2016 MindView LLC: see Copyright.txt
+// We make no guarantees that this code is fit for any purpose.
+// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
+// {ValidateByHand} // Don't run by itself
+import java.util.*;
+import org.junit.*;
+import static org.junit.Assert.*;
+import org.junit.runner.*;
+import org.junit.runner.notification.Failure;
+
+public class StringInverterTest {
+  static StringInverter inverter;
+  @Test
+  public final void basicInversion_Succeed() {
+    String in = "Exit, Pursued by a Bear.";
+    String out = "eXIT, pURSUED BY A bEAR.";
+    assertEquals(inverter.invert(in), out);
+  }
+  @Test(expected = ComparisonFailure.class)
+  public final void basicInversion_Fail() {
+    assertEquals(inverter.invert("X"), "X");
+  }
+  @Test(expected = RuntimeException.class)
+  public final void allowedCharacters_Fail() {
+    inverter.invert(";-_()*&^%$#@!~`");
+    inverter.invert("0123456789");
+  }
+  /*@Test
+  public final void allowedCharacters_Succeed() {
+    inverter.invert("abcdefghijklmnopqrstuvwxyz ,.");
+    inverter.invert("ABCDEFGHIJKLMNOPQRSTUVWXYZ ,.");
+    assertTrue(true); // No exception thrown
+  }*/
+  @Test(expected = RuntimeException.class)
+  public final void lengthLessThan26_Fail() {
+    String str = "xxxxxxxxxxxxxxxxxxxxxxxxxx";
+    assertTrue(str.length() > 25);
+    inverter.invert(str);
+  }
+  @Test
+  public final void lengthLessThan26_Succeed() {
+    String str = "xxxxxxxxxxxxxxxxxxxxxxxxx";
+    assertTrue(str.length() < 26);
+    inverter.invert(str);
+    assertTrue(true); // No exception thrown
+  }
+  public static void main(String[] args) throws Exception{
+    assertEquals(args.length, 1);
+    inverter = (StringInverter)
+      Class.forName(args[0]).newInstance();
+    Result result = JUnitCore.runClasses(
+      StringInverterTest.class);
+    List<Failure> failures = result.getFailures();
+    System.out.printf("%s has %d FAILURES:\n",
+      args[0], failures.size());
+    int count = 1;
+    for(Failure f : failures) {
+      System.out.printf("Failure %d:\n", count++);
+      System.out.println(f.getDescription());
+      System.out.println(f.getMessage());
+    }
+  }
+}

verifying/logback.xml

@@ -9,4 +9,4 @@
   <root level="TRACE">
     <appender-ref ref="STDOUT" />
   </root>
-</configuration>
+</configuration>