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/*
* Copyright (C) 2007 The Guava Authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.common.collect.testing.testers;
import static com.google.common.collect.testing.features.CollectionFeature.KNOWN_ORDER;
import static com.google.common.collect.testing.features.CollectionSize.ZERO;
import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.collect.testing.AbstractCollectionTester;
import com.google.common.collect.testing.Helpers;
import com.google.common.collect.testing.WrongType;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
/**
* A generic JUnit test which tests {@code toArray()} operations on a collection. Can't be invoked
* directly; please see {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}.
*
* @author Kevin Bourrillion
* @author Chris Povirk
*/
@GwtCompatible(emulated = true)
public class CollectionToArrayTester extends AbstractCollectionTester {
public void testToArray_noArgs() {
Object[] array = collection.toArray();
expectArrayContentsAnyOrder(createSamplesArray(), array);
}
/**
* {@link Collection#toArray(Object[])} says: "Note that toArray(new Object[0]) is
* identical in function to toArray()."
*
* For maximum effect, the collection under test should be created from an element array of a
* type other than {@code Object[]}.
*/
public void testToArray_isPlainObjectArray() {
Object[] array = collection.toArray();
assertEquals(Object[].class, array.getClass());
}
public void testToArray_emptyArray() {
E[] empty = getSubjectGenerator().createArray(0);
E[] array = collection.toArray(empty);
assertEquals(
"toArray(emptyT[]) should return an array of type T", empty.getClass(), array.getClass());
assertEquals("toArray(emptyT[]).length:", getNumElements(), array.length);
expectArrayContentsAnyOrder(createSamplesArray(), array);
}
@CollectionFeature.Require(KNOWN_ORDER)
public void testToArray_emptyArray_ordered() {
E[] empty = getSubjectGenerator().createArray(0);
E[] array = collection.toArray(empty);
assertEquals(
"toArray(emptyT[]) should return an array of type T", empty.getClass(), array.getClass());
assertEquals("toArray(emptyT[]).length:", getNumElements(), array.length);
expectArrayContentsInOrder(getOrderedElements(), array);
}
public void testToArray_emptyArrayOfObject() {
Object[] in = new Object[0];
Object[] array = collection.toArray(in);
assertEquals(
"toArray(emptyObject[]) should return an array of type Object",
Object[].class,
array.getClass());
assertEquals("toArray(emptyObject[]).length", getNumElements(), array.length);
expectArrayContentsAnyOrder(createSamplesArray(), array);
}
public void testToArray_rightSizedArray() {
E[] array = getSubjectGenerator().createArray(getNumElements());
assertSame(
"toArray(sameSizeE[]) should return the given array", array, collection.toArray(array));
expectArrayContentsAnyOrder(createSamplesArray(), array);
}
@CollectionFeature.Require(KNOWN_ORDER)
public void testToArray_rightSizedArray_ordered() {
E[] array = getSubjectGenerator().createArray(getNumElements());
assertSame(
"toArray(sameSizeE[]) should return the given array", array, collection.toArray(array));
expectArrayContentsInOrder(getOrderedElements(), array);
}
public void testToArray_rightSizedArrayOfObject() {
Object[] array = new Object[getNumElements()];
assertSame(
"toArray(sameSizeObject[]) should return the given array",
array,
collection.toArray(array));
expectArrayContentsAnyOrder(createSamplesArray(), array);
}
@CollectionFeature.Require(KNOWN_ORDER)
public void testToArray_rightSizedArrayOfObject_ordered() {
Object[] array = new Object[getNumElements()];
assertSame(
"toArray(sameSizeObject[]) should return the given array",
array,
collection.toArray(array));
expectArrayContentsInOrder(getOrderedElements(), array);
}
public void testToArray_oversizedArray() {
E[] array = getSubjectGenerator().createArray(getNumElements() + 2);
array[getNumElements()] = e3();
array[getNumElements() + 1] = e3();
assertSame(
"toArray(overSizedE[]) should return the given array", array, collection.toArray(array));
List subArray = Arrays.asList(array).subList(0, getNumElements());
E[] expectedSubArray = createSamplesArray();
for (int i = 0; i < getNumElements(); i++) {
assertTrue(
"toArray(overSizedE[]) should contain element " + expectedSubArray[i],
subArray.contains(expectedSubArray[i]));
}
assertNull(
"The array element immediately following the end of the collection should be nulled",
array[getNumElements()]);
// array[getNumElements() + 1] might or might not have been nulled
}
@CollectionFeature.Require(KNOWN_ORDER)
public void testToArray_oversizedArray_ordered() {
E[] array = getSubjectGenerator().createArray(getNumElements() + 2);
array[getNumElements()] = e3();
array[getNumElements() + 1] = e3();
assertSame(
"toArray(overSizedE[]) should return the given array", array, collection.toArray(array));
List expected = getOrderedElements();
for (int i = 0; i < getNumElements(); i++) {
assertEquals(expected.get(i), array[i]);
}
assertNull(
"The array element immediately following the end of the collection should be nulled",
array[getNumElements()]);
// array[getNumElements() + 1] might or might not have been nulled
}
@CollectionSize.Require(absent = ZERO)
public void testToArray_emptyArrayOfWrongTypeForNonEmptyCollection() {
try {
WrongType[] array = new WrongType[0];
collection.toArray(array);
fail("toArray(notAssignableTo[]) should throw");
} catch (ArrayStoreException expected) {
}
}
@CollectionSize.Require(ZERO)
public void testToArray_emptyArrayOfWrongTypeForEmptyCollection() {
WrongType[] array = new WrongType[0];
assertSame(
"toArray(sameSizeNotAssignableTo[]) should return the given array",
array,
collection.toArray(array));
}
private void expectArrayContentsAnyOrder(Object[] expected, Object[] actual) {
Helpers.assertEqualIgnoringOrder(Arrays.asList(expected), Arrays.asList(actual));
}
private void expectArrayContentsInOrder(List expected, Object[] actual) {
assertEquals("toArray() ordered contents: ", expected, Arrays.asList(actual));
}
/**
* Returns the {@link Method} instance for {@link #testToArray_isPlainObjectArray()} so that tests
* of {@link Arrays#asList(Object[])} can suppress it with {@code
* FeatureSpecificTestSuiteBuilder.suppressing()} until Sun bug 6260652 is fixed.
*/
@GwtIncompatible // reflection
public static Method getToArrayIsPlainObjectArrayMethod() {
return Helpers.getMethod(CollectionToArrayTester.class, "testToArray_isPlainObjectArray");
}
}