TestCase.java revision 58a8b0aba2dec5695628a2bf25a3fae42c2c3533
1package junit.framework;
2
3import java.lang.reflect.InvocationTargetException;
4import java.lang.reflect.Method;
5import java.lang.reflect.Modifier;
6
7/**
8 * A test case defines the fixture to run multiple tests. To define a test case<br>
9 * 1) implement a subclass of TestCase<br>
10 * 2) define instance variables that store the state of the fixture<br>
11 * 3) initialize the fixture state by overriding <code>setUp</code><br>
12 * 4) clean-up after a test by overriding <code>tearDown</code>.<br>
13 * Each test runs in its own fixture so there
14 * can be no side effects among test runs.
15 * Here is an example:
16 * <pre>
17 * public class MathTest extends TestCase {
18 *     protected double fValue1;
19 *     protected double fValue2;
20 *
21 *    protected void setUp() {
22 *         fValue1= 2.0;
23 *         fValue2= 3.0;
24 *     }
25 * }
26 * </pre>
27 *
28 * For each test implement a method which interacts
29 * with the fixture. Verify the expected results with assertions specified
30 * by calling <code>assertTrue</code> with a boolean.
31 * <pre>
32 *    public void testAdd() {
33 *        double result= fValue1 + fValue2;
34 *        assertTrue(result == 5.0);
35 *    }
36 * </pre>
37 * Once the methods are defined you can run them. The framework supports
38 * both a static type safe and more dynamic way to run a test.
39 * In the static way you override the runTest method and define the method to
40 * be invoked. A convenient way to do so is with an anonymous inner class.
41 * <pre>
42 * TestCase test= new MathTest("add") {
43 *        public void runTest() {
44 *            testAdd();
45 *        }
46 * };
47 * test.run();
48 * </pre>
49 * The dynamic way uses reflection to implement <code>runTest</code>. It dynamically finds
50 * and invokes a method.
51 * In this case the name of the test case has to correspond to the test method
52 * to be run.
53 * <pre>
54 * TestCase test= new MathTest("testAdd");
55 * test.run();
56 * </pre>
57 * The tests to be run can be collected into a TestSuite. JUnit provides
58 * different <i>test runners</i> which can run a test suite and collect the results.
59 * A test runner either expects a static method <code>suite</code> as the entry
60 * point to get a test to run or it will extract the suite automatically.
61 * <pre>
62 * public static Test suite() {
63 *      suite.addTest(new MathTest("testAdd"));
64 *      suite.addTest(new MathTest("testDivideByZero"));
65 *      return suite;
66 *  }
67 * </pre>
68 * @see TestResult
69 * @see TestSuite
70 */
71
72public abstract class TestCase extends Assert implements Test {
73	/**
74	 * the name of the test case
75	 */
76	private String fName;
77
78	/**
79	 * No-arg constructor to enable serialization. This method
80	 * is not intended to be used by mere mortals without calling setName().
81	 */
82	public TestCase() {
83		fName= null;
84	}
85	/**
86	 * Constructs a test case with the given name.
87	 */
88	public TestCase(String name) {
89		fName= name;
90	}
91	/**
92	 * Counts the number of test cases executed by run(TestResult result).
93	 */
94	public int countTestCases() {
95		return 1;
96	}
97	/**
98	 * Creates a default TestResult object
99	 *
100	 * @see TestResult
101	 */
102	protected TestResult createResult() {
103	    return new TestResult();
104	}
105	/**
106	 * A convenience method to run this test, collecting the results with a
107	 * default TestResult object.
108	 *
109	 * @see TestResult
110	 */
111	public TestResult run() {
112		TestResult result= createResult();
113		run(result);
114		return result;
115	}
116	/**
117	 * Runs the test case and collects the results in TestResult.
118	 */
119	public void run(TestResult result) {
120		result.run(this);
121	}
122	/**
123	 * Runs the bare test sequence.
124	 * @exception Throwable if any exception is thrown
125	 */
126	public void runBare() throws Throwable {
127		Throwable exception= null;
128		setUp();
129		try {
130			runTest();
131		} catch (Throwable running) {
132			exception= running;
133		}
134		finally {
135			try {
136				tearDown();
137			} catch (Throwable tearingDown) {
138				if (exception == null) exception= tearingDown;
139			}
140		}
141		if (exception != null) throw exception;
142	}
143	/**
144	 * Override to run the test and assert its state.
145	 * @exception Throwable if any exception is thrown
146	 */
147	protected void runTest() throws Throwable {
148		assertNotNull(fName); // Some VMs crash when calling getMethod(null,null);
149		Method runMethod= null;
150		try {
151			// use getMethod to get all public inherited
152			// methods. getDeclaredMethods returns all
153			// methods of this class but excludes the
154			// inherited ones.
155			runMethod= getClass().getMethod(fName, (Class[])null);
156		} catch (NoSuchMethodException e) {
157			fail("Method \""+fName+"\" not found");
158		}
159		if (!Modifier.isPublic(runMethod.getModifiers())) {
160			fail("Method \""+fName+"\" should be public");
161		}
162
163		try {
164			runMethod.invoke(this, (Object[])new Class[0]);
165		}
166		catch (InvocationTargetException e) {
167			e.fillInStackTrace();
168			throw e.getTargetException();
169		}
170		catch (IllegalAccessException e) {
171			e.fillInStackTrace();
172			throw e;
173		}
174	}
175	/**
176	 * Sets up the fixture, for example, open a network connection.
177	 * This method is called before a test is executed.
178	 */
179	protected void setUp() throws Exception {
180	}
181	/**
182	 * Tears down the fixture, for example, close a network connection.
183	 * This method is called after a test is executed.
184	 */
185	protected void tearDown() throws Exception {
186	}
187	/**
188	 * Returns a string representation of the test case
189	 */
190	public String toString() {
191	    return getName() + "(" + getClass().getName() + ")";
192	}
193	/**
194	 * Gets the name of a TestCase
195	 * @return returns a String
196	 */
197	public String getName() {
198		return fName;
199	}
200	/**
201	 * Sets the name of a TestCase
202	 * @param name The name to set
203	 */
204	public void setName(String name) {
205		fName= name;
206	}
207}
208