Source code
package org.junit.runner;
import java.io.Serializable;
import java.lang.annotation.Annotation;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* A <code>Description</code> describes a test which is to be run or has been run. <code>Descriptions</code>
* can be atomic (a single test) or compound (containing children tests). <code>Descriptions</code> are used
* to provide feedback about the tests that are about to run (for example, the tree view
* visible in many IDEs) or tests that have been run (for example, the failures view).
* <p>
* <code>Descriptions</code> are implemented as a single class rather than a Composite because
* they are entirely informational. They contain no logic aside from counting their tests.
* <p>
* In the past, we used the raw {@link junit.framework.TestCase}s and {@link junit.framework.TestSuite}s
* to display the tree of tests. This was no longer viable in JUnit 4 because atomic tests no longer have
* a superclass below {@link Object}. We needed a way to pass a class and name together. Description
* emerged from this.
*
* @see org.junit.runner.Request
* @see org.junit.runner.Runner
* @since 4.0
*/
public class Description implements Serializable {
private static final long serialVersionUID = 1L;
private static final Pattern METHOD_AND_CLASS_NAME_PATTERN = Pattern
.compile("(.*)\\((.*)\\)");
/**
* Create a <code>Description</code> named <code>name</code>.
* Generally, you will add children to this <code>Description</code>.
*
* @param name the name of the <code>Description</code>
* @param annotations meta-data about the test, for downstream interpreters
* @return a <code>Description</code> named <code>name</code>
*/
public static Description createSuiteDescription(String name, Annotation... annotations) {
return new Description(null, name, annotations);
}
/**
* Create a <code>Description</code> named <code>name</code>.
* Generally, you will add children to this <code>Description</code>.
*
* @param name the name of the <code>Description</code>
* @param uniqueId an arbitrary object used to define uniqueness (in {@link #equals(Object)}
* @param annotations meta-data about the test, for downstream interpreters
* @return a <code>Description</code> named <code>name</code>
*/
public static Description createSuiteDescription(String name, Serializable uniqueId, Annotation... annotations) {
return new Description(null, name, uniqueId, annotations);
}
/**
* Create a <code>Description</code> of a single test named <code>name</code> in the 'class' named
* <code>className</code>. Generally, this will be a leaf <code>Description</code>. This method is a better choice
* than {@link #createTestDescription(Class, String, Annotation...)} for test runners whose test cases are not
* defined in an actual Java <code>Class</code>.
*
* @param className the class name of the test
* @param name the name of the test (a method name for test annotated with {@link org.junit.Test})
* @param annotations meta-data about the test, for downstream interpreters
* @return a <code>Description</code> named <code>name</code>
*/
public static Description createTestDescription(String className, String name, Annotation... annotations) {
return new Description(null, formatDisplayName(name, className), annotations);
}
/**
* Create a <code>Description</code> of a single test named <code>name</code> in the class <code>clazz</code>.
* Generally, this will be a leaf <code>Description</code>.
*
* @param clazz the class of the test
* @param name the name of the test (a method name for test annotated with {@link org.junit.Test})
* @param annotations meta-data about the test, for downstream interpreters
* @return a <code>Description</code> named <code>name</code>
*/
public static Description createTestDescription(Class<?> clazz, String name, Annotation... annotations) {
return new Description(clazz, formatDisplayName(name, clazz.getName()), annotations);
}
/**
* Create a <code>Description</code> of a single test named <code>name</code> in the class <code>clazz</code>.
* Generally, this will be a leaf <code>Description</code>.
* (This remains for binary compatibility with clients of JUnit 4.3)
*
* @param clazz the class of the test
* @param name the name of the test (a method name for test annotated with {@link org.junit.Test})
* @return a <code>Description</code> named <code>name</code>
*/
public static Description createTestDescription(Class<?> clazz, String name) {
return new Description(clazz, formatDisplayName(name, clazz.getName()));
}
/**
* Create a <code>Description</code> of a single test named <code>name</code> in the class <code>clazz</code>.
* Generally, this will be a leaf <code>Description</code>.
*
* @param name the name of the test (a method name for test annotated with {@link org.junit.Test})
* @return a <code>Description</code> named <code>name</code>
*/
public static Description createTestDescription(String className, String name, Serializable uniqueId) {
return new Description(null, formatDisplayName(name, className), uniqueId);
}
private static String formatDisplayName(String name, String className) {
return String.format("%s(%s)", name, className);
}
/**
* Create a <code>Description</code> named after <code>testClass</code>
*
* @param testClass A {@link Class} containing tests
* @return a <code>Description</code> of <code>testClass</code>
*/
public static Description createSuiteDescription(Class<?> testClass) {
return new Description(testClass, testClass.getName(), testClass.getAnnotations());
}
/**
* Describes a Runner which runs no tests
*/
public static final Description EMPTY = new Description(null, "No Tests");
/**
* Describes a step in the test-running mechanism that goes so wrong no
* other description can be used (for example, an exception thrown from a Runner's
* constructor
*/
public static final Description TEST_MECHANISM = new Description(null, "Test mechanism");
private final Collection<Description> fChildren = new ConcurrentLinkedQueue<Description>();
private final String fDisplayName;
private final Serializable fUniqueId;
private final Annotation[] fAnnotations;
private volatile /* write-once */ Class<?> fTestClass;
private Description(Class<?> clazz, String displayName, Annotation... annotations) {
this(clazz, displayName, displayName, annotations);
}
private Description(Class<?> clazz, String displayName, Serializable uniqueId, Annotation... annotations) {
if ((displayName == null) || (displayName.length() == 0)) {
throw new IllegalArgumentException(
"The display name must not be empty.");
}
if ((uniqueId == null)) {
throw new IllegalArgumentException(
"The unique id must not be null.");
}
fTestClass = clazz;
fDisplayName = displayName;
fUniqueId = uniqueId;
fAnnotations = annotations;
}
/**
* @return a user-understandable label
*/
public String getDisplayName() {
return fDisplayName;
}
/**
* Add <code>Description</code> as a child of the receiver.
*
* @param description the soon-to-be child.
*/
public void addChild(Description description) {
fChildren.add(description);
}
/**
* Gets the copy of the children of this {@code Description}.
* Returns an empty list if there are no children.
*/
public ArrayList<Description> getChildren() {
return new ArrayList<Description>(fChildren);
}
/**
* @return <code>true</code> if the receiver is a suite
*/
public boolean isSuite() {
return !isTest();
}
/**
* @return <code>true</code> if the receiver is an atomic test
*/
public boolean isTest() {
return fChildren.isEmpty();
}
/**
* @return the total number of atomic tests in the receiver
*/
public int testCount() {
if (isTest()) {
return 1;
}
int result = 0;
for (Description child : fChildren) {
result += child.testCount();
}
return result;
}
@Override
public int hashCode() {
return fUniqueId.hashCode();
}
@Override
public boolean equals(Object obj) {
if (!(obj instanceof Description)) {
return false;
}
Description d = (Description) obj;
return fUniqueId.equals(d.fUniqueId);
}
@Override
public String toString() {
return getDisplayName();
}
/**
* @return true if this is a description of a Runner that runs no tests
*/
public boolean isEmpty() {
return equals(EMPTY);
}
/**
* @return a copy of this description, with no children (on the assumption that some of the
* children will be added back)
*/
public Description childlessCopy() {
return new Description(fTestClass, fDisplayName, fAnnotations);
}
/**
* @return the annotation of type annotationType that is attached to this description node,
* or null if none exists
*/
public <T extends Annotation> T getAnnotation(Class<T> annotationType) {
for (Annotation each : fAnnotations) {
if (each.annotationType().equals(annotationType)) {
return annotationType.cast(each);
}
}
return null;
}
/**
* @return all of the annotations attached to this description node
*/
public Collection<Annotation> getAnnotations() {
return Arrays.asList(fAnnotations);
}
/**
* @return If this describes a method invocation,
* the class of the test instance.
*/
public Class<?> getTestClass() {
if (fTestClass != null) {
return fTestClass;
}
String name = getClassName();
if (name == null) {
return null;
}
try {
fTestClass = Class.forName(name, false, getClass().getClassLoader());
return fTestClass;
} catch (ClassNotFoundException e) {
return null;
}
}
/**
* @return If this describes a method invocation,
* the name of the class of the test instance
*/
public String getClassName() {
return fTestClass != null ? fTestClass.getName() : methodAndClassNamePatternGroupOrDefault(2, toString());
}
/**
* @return If this describes a method invocation,
* the name of the method (or null if not)
*/
public String getMethodName() {
return methodAndClassNamePatternGroupOrDefault(1, null);
}
private String methodAndClassNamePatternGroupOrDefault(int group,
String defaultString) {
Matcher matcher = METHOD_AND_CLASS_NAME_PATTERN.matcher(toString());
return matcher.matches() ? matcher.group(group) : defaultString;
}
}