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/*
* Copyright (C) 2008 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.features;
import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.Helpers;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.Collection;
import java.util.Collections;
import java.util.Set;
/**
* When describing the features of the collection produced by a given generator
* (i.e. in a call to {@link
* com.google.common.collect.testing.FeatureSpecificTestSuiteBuilder#withFeatures(Feature...)}),
* this annotation specifies each of the different sizes for which a test suite
* should be built. (In a typical case, the features should include {@link
* CollectionSize#ANY}.) These semantics are thus a little different
* from those of other Collection-related features such as {@link
* CollectionFeature} or {@link SetFeature}.
*
* However, when {@link CollectionSize.Require} is used to annotate a test it
* behaves normally (i.e. it requires the collection instance under test to be
* a certain size for the test to run). Note that this means a test should not
* require more than one CollectionSize, since a particular collection instance
* can only be one size at once.
*
* @author George van den Driessche
*/
// Enum values use constructors with generic varargs.
@SuppressWarnings("unchecked")
@GwtCompatible
public enum CollectionSize implements Feature,
Comparable {
/** Test an empty collection. */
ZERO(0),
/** Test a one-element collection. */
ONE(1),
/** Test a three-element collection. */
SEVERAL(3),
/*
* TODO: add VERY_LARGE, noting that we currently assume that the fourth
* sample element is not in any collection
*/
ANY(
ZERO,
ONE,
SEVERAL
);
private final Set> implied;
private final Integer numElements;
CollectionSize(int numElements) {
this.implied = Collections.emptySet();
this.numElements = numElements;
}
CollectionSize(Feature ... implied) {
// Keep the order here, so that PerCollectionSizeTestSuiteBuilder
// gives a predictable order of test suites.
this.implied = Helpers.copyToSet(implied);
this.numElements = null;
}
@Override
public Set> getImpliedFeatures() {
return implied;
}
public int getNumElements() {
if (numElements == null) {
throw new IllegalStateException(
"A compound CollectionSize doesn't specify a number of elements.");
}
return numElements;
}
@Retention(RetentionPolicy.RUNTIME)
@Inherited
@TesterAnnotation
public @interface Require {
CollectionSize[] value() default {};
CollectionSize[] absent() default {};
}
}