repacked.com.google.common.collect.Iterables Maven / Gradle / Ivy
package repacked.com.google.common.collect;
import repacked.com.google.common.base.Function;
import repacked.com.google.common.base.Predicate;
import java.util.Collection;
import java.util.Iterator;
/**
* Copyright (C) 2010 RapidPM
* 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.
*
* Created by RapidPM - Team on 19.09.16.
*/
public class Iterables {
private Iterables() {
}
/**
* Returns a view of {@code unfiltered} containing all elements that satisfy
* the input predicate {@code retainIfTrue}. The returned iterable's iterator
* does not support {@code remove()}.
*/
public static Iterable filter(
final Iterable unfiltered,
final Predicate retainIfTrue) {
if (unfiltered == null || retainIfTrue == null) throw new NullPointerException();
return new FluentIterable() {
@Override
public Iterator iterator() {
return Iterators.filter(unfiltered.iterator(), retainIfTrue);
}
};
}
/**
* Combines two iterables into a single iterable. The returned iterable has an
* iterator that traverses the elements in {@code a}, followed by the elements
* in {@code b}. The source iterators are not polled until necessary.
*
* The returned iterable's iterator supports {@code remove()} when the
* corresponding input iterator supports it.
*/
public static Iterable concat(Iterable a, Iterable b) {
return FluentIterable.concat(a, b);
}
/**
* Combines multiple iterables into a single iterable. The returned iterable
* has an iterator that traverses the elements of each iterable in
* {@code inputs}. The input iterators are not polled until necessary.
*
* The returned iterable's iterator supports {@code remove()} when the
* corresponding input iterator supports it. The methods of the returned
* iterable may throw {@code NullPointerException} if any of the input
* iterators is null.
*/
public static Iterable concat(Iterable> inputs) {
return FluentIterable.concat(inputs);
}
public static boolean isEmpty(final Iterable iterable) {
if (iterable instanceof Collection) {
return ((Collection) iterable).isEmpty();
}
return !iterable.iterator().hasNext();
}
public static T getOnlyElement(final Iterable iterable) {
final Iterator iterator = iterable.iterator();
return Iterators.getOnlyElement(iterator);
}
public static boolean any(Iterable iterable, Predicate predicate) {
return Iterators.any(iterable.iterator(), predicate);
}
public static boolean contains(final Iterable iterable, final Object element) {
if (iterable instanceof Collection) {
Collection collection = (Collection) iterable;
return Collections2.safeContains(collection, element);
}
return Iterators.contains(iterable.iterator(), element);
}
public static Iterable transform(
final Iterable fromIterable, final Function function) {
return new FluentIterable() {
@Override
public Iterator iterator() {
return Iterators.transform(fromIterable.iterator(), function);
}
};
}
public static Iterable limit(final Iterable iterable, final int limitSize) {
return new FluentIterable() {
@Override
public Iterator iterator() {
return Iterators.limit(iterable.iterator(), limitSize);
}
};
}
}