package com.skraylabs.poker;

import static org.hamcrest.CoreMatchers.allOf;
import static org.hamcrest.CoreMatchers.containsString;
import static org.hamcrest.MatcherAssert.assertThat;

import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.ByteArrayOutputStream;
import java.io.PrintStream;

public class ApplicationTest {

  @Before
  public void setUp() throws Exception {}

  @After
  public void tearDown() throws Exception {}

  @Test
  public void testShowUsageForTooFewArguments() {
    // Set up
    ByteArrayOutputStream output = new ByteArrayOutputStream();
    PrintStream console = System.out;
    try {
      System.setOut(new PrintStream(output));
      String[] args = {""};
      // Exercise
      Application.main(args);
    } finally {
      // Tear down
      System.setOut(console);
    }
    // Verify
    String outputString = output.toString();
    assertThat(outputString, allOf(containsString("Too few arguments"),
        containsString("Usage: PokerCalculator filepath")));
  }

}

package com.skraylabs.poker;

import static org.junit.Assert.fail;

import org.junit.After;
import org.junit.Before;
import org.junit.Test;

public class ApplicationTest {

  @Before
  public void setUp() throws Exception {}

  @After
  public void tearDown() throws Exception {}

  @Test
  public void test() {
    fail("Not yet implemented");
  }

}

--- 
+++ 
@@ -1,10 +1,15 @@
 package com.skraylabs.poker;
 
-import static org.junit.Assert.fail;
+import static org.hamcrest.CoreMatchers.allOf;
+import static org.hamcrest.CoreMatchers.containsString;
+import static org.hamcrest.MatcherAssert.assertThat;
 
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
 
 public class ApplicationTest {
 
@@ -15,8 +20,23 @@
   public void tearDown() throws Exception {}
 
   @Test
-  public void test() {
-    fail("Not yet implemented");
+  public void testShowUsageForTooFewArguments() {
+    // Set up
+    ByteArrayOutputStream output = new ByteArrayOutputStream();
+    PrintStream console = System.out;
+    try {
+      System.setOut(new PrintStream(output));
+      String[] args = {""};
+      // Exercise
+      Application.main(args);
+    } finally {
+      // Tear down
+      System.setOut(console);
+    }
+    // Verify
+    String outputString = output.toString();
+    assertThat(outputString, allOf(containsString("Too few arguments"),
+        containsString("Usage: PokerCalculator filepath")));
   }
 
 }
Implement test for too few arguments.

Following example at:
http://www.developer.com/tech/article.php/3669436/Test-Driving-a-Java-Command-Line-Application.htm