org.junit.internal.ComparisonCriteria Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of junit Show documentation
Show all versions of junit Show documentation
JUnit is a unit testing framework for Java, created by Erich Gamma and Kent Beck.
package org.junit.internal;
import java.lang.reflect.Array;
import java.util.Arrays;
import org.junit.Assert;
/**
* Defines criteria for finding two items "equal enough". Concrete subclasses
* may demand exact equality, or, for example, equality within a given delta.
*/
public abstract class ComparisonCriteria {
/**
* Asserts that two arrays are equal, according to the criteria defined by
* the concrete subclass. If they are not, an {@link AssertionError} is
* thrown with the given message. If expecteds
and
* actuals
are null
, they are considered equal.
*
* @param message the identifying message for the {@link AssertionError} (
* null
okay)
* @param expecteds Object array or array of arrays (multi-dimensional array) with
* expected values.
* @param actuals Object array or array of arrays (multi-dimensional array) with
* actual values
*/
public void arrayEquals(String message, Object expecteds, Object actuals)
throws ArrayComparisonFailure {
arrayEquals(message, expecteds, actuals, true);
}
private void arrayEquals(String message, Object expecteds, Object actuals, boolean outer)
throws ArrayComparisonFailure {
if (expecteds == actuals
|| Arrays.deepEquals(new Object[] {expecteds}, new Object[] {actuals})) {
// The reflection-based loop below is potentially very slow, especially for primitive
// arrays. The deepEquals check allows us to circumvent it in the usual case where
// the arrays are exactly equal.
return;
}
String header = message == null ? "" : message + ": ";
// Only include the user-provided message in the outer exception.
String exceptionMessage = outer ? header : "";
if (expecteds == null) {
Assert.fail(exceptionMessage + "expected array was null");
}
if (actuals == null) {
Assert.fail(exceptionMessage + "actual array was null");
}
int actualsLength = Array.getLength(actuals);
int expectedsLength = Array.getLength(expecteds);
if (actualsLength != expectedsLength) {
header += "array lengths differed, expected.length="
+ expectedsLength + " actual.length=" + actualsLength + "; ";
}
int prefixLength = Math.min(actualsLength, expectedsLength);
for (int i = 0; i < prefixLength; i++) {
Object expected = Array.get(expecteds, i);
Object actual = Array.get(actuals, i);
if (isArray(expected) && isArray(actual)) {
try {
arrayEquals(message, expected, actual, false);
} catch (ArrayComparisonFailure e) {
e.addDimension(i);
throw e;
} catch (AssertionError e) {
// Array lengths differed.
throw new ArrayComparisonFailure(header, e, i);
}
} else {
try {
assertElementsEqual(expected, actual);
} catch (AssertionError e) {
throw new ArrayComparisonFailure(header, e, i);
}
}
}
if (actualsLength != expectedsLength) {
Object expected = getToStringableArrayElement(expecteds, expectedsLength, prefixLength);
Object actual = getToStringableArrayElement(actuals, actualsLength, prefixLength);
try {
Assert.assertEquals(expected, actual);
} catch (AssertionError e) {
throw new ArrayComparisonFailure(header, e, prefixLength);
}
}
}
private static final Object END_OF_ARRAY_SENTINEL = objectWithToString("end of array");
private Object getToStringableArrayElement(Object array, int length, int index) {
if (index < length) {
Object element = Array.get(array, index);
if (isArray(element)) {
return objectWithToString(componentTypeName(element.getClass()) + "[" + Array.getLength(element) + "]");
} else {
return element;
}
} else {
return END_OF_ARRAY_SENTINEL;
}
}
private static Object objectWithToString(final String string) {
return new Object() {
@Override
public String toString() {
return string;
}
};
}
private String componentTypeName(Class arrayClass) {
Class componentType = arrayClass.getComponentType();
if (componentType.isArray()) {
return componentTypeName(componentType) + "[]";
} else {
return componentType.getName();
}
}
private boolean isArray(Object expected) {
return expected != null && expected.getClass().isArray();
}
protected abstract void assertElementsEqual(Object expected, Object actual);
}