A sample Stack test.

gistfile1.java

package demo;

import org.junit.runner.RunWith;
import org.junit.runners.Suite;
import org.junit.runners.Suite.SuiteClasses;

@RunWith(Suite.class)
@SuiteClasses({EmptyStack.class, StackWithOneElement.class})
public class StackTest {
}

package demo;

import java.util.Stack;

public abstract class AbstractStackTest {

  protected Stack<String> subject = new Stack<String>();
}


package demo;

import java.util.EmptyStackException;

import org.junit.Test;
import static org.hamcrest.CoreMatchers.*;
import static org.junit.Assert.*;

public class EmptyStack extends AbstractStackTest {
  @Test
  public void shouldHaveSizeZero() throws Exception {
    assertThat(subject.size(), is(0));
  }

  @Test(expected = EmptyStackException.class)
  public void shouldThrowExceptionOnPop() throws Exception {
    subject.pop();
  }
}

package demo;

import org.junit.Before;
import org.junit.Test;
import static org.hamcrest.CoreMatchers.*;
import static org.junit.Assert.*;

public class StackWithOneElement extends AbstractStackTest {
  @Before
  public void setup() {
    subject.add("something");
  }

  @Test
  public void shouldHaveSizeOne() throws Exception {
    assertThat(subject.size(), is(1));
  }

  @Test
  public void shouldDecreaseSizeOnPop() throws Exception {
    subject.pop();
    assertThat(subject.size(), is(0));
  }
}