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*
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* notice, this list of conditions and the following disclaimer.
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* copyright notice, this list of conditions and the following disclaimer
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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package org.jf.util;
import com.google.common.base.Predicate;
import com.google.common.collect.ImmutableSortedSet;
import com.google.common.collect.Ordering;
import com.google.common.primitives.Ints;
import javax.annotation.Nonnull;
import java.util.*;
public class CollectionUtils {
public static <T> int listHashCode(@Nonnull Iterable<T> iterable) {
int hashCode = 1;
for (T item: iterable) {
hashCode = hashCode*31 + item.hashCode();
}
return hashCode;
}
public static <T> int lastIndexOf(@Nonnull Iterable<T> iterable, @Nonnull Predicate<? super T> predicate) {
int index = 0;
int lastMatchingIndex = -1;
for (T item: iterable) {
if (predicate.apply(item)) {
lastMatchingIndex = index;
}
index++;
}
return lastMatchingIndex;
}
public static <T extends Comparable<? super T>> int compareAsList(@Nonnull Collection<? extends T> list1,
@Nonnull Collection<? extends T> list2) {
int res = Ints.compare(list1.size(), list2.size());
if (res != 0) return res;
Iterator<? extends T> elements2 = list2.iterator();
for (T element1: list1) {
res = element1.compareTo(elements2.next());
if (res != 0) return res;
}
return 0;
}
public static <T> int compareAsIterable(@Nonnull Comparator<? super T> comparator,
@Nonnull Iterable<? extends T> it1,
@Nonnull Iterable<? extends T> it2) {
Iterator<? extends T> elements2 = it2.iterator();
for (T element1: it1) {
T element2;
try {
element2 = elements2.next();
} catch (NoSuchElementException ex) {
return 1;
}
int res = comparator.compare(element1, element2);
if (res != 0) return res;
}
if (elements2.hasNext()) {
return -1;
}
return 0;
}
public static <T extends Comparable<? super T>> int compareAsIterable(@Nonnull Iterable<? extends T> it1,
@Nonnull Iterable<? extends T> it2) {
Iterator<? extends T> elements2 = it2.iterator();
for (T element1: it1) {
T element2;
try {
element2 = elements2.next();
} catch (NoSuchElementException ex) {
return 1;
}
int res = element1.compareTo(element2);
if (res != 0) return res;
}
if (elements2.hasNext()) {
return -1;
}
return 0;
}
public static <T> int compareAsList(@Nonnull Comparator<? super T> elementComparator,
@Nonnull Collection<? extends T> list1,
@Nonnull Collection<? extends T> list2) {
int res = Ints.compare(list1.size(), list2.size());
if (res != 0) return res;
Iterator<? extends T> elements2 = list2.iterator();
for (T element1: list1) {
res = elementComparator.compare(element1, elements2.next());
if (res != 0) return res;
}
return 0;
}
@Nonnull
public static <T> Comparator<Collection<? extends T>> listComparator(
@Nonnull final Comparator<? super T> elementComparator) {
return new Comparator<Collection<? extends T>>() {
@Override
public int compare(Collection<? extends T> list1, Collection<? extends T> list2) {
return compareAsList(elementComparator, list1, list2);
}
};
}
public static <T> boolean isNaturalSortedSet(@Nonnull Iterable<? extends T> it) {
if (it instanceof SortedSet) {
SortedSet<? extends T> sortedSet = (SortedSet<? extends T>)it;
Comparator<?> comparator = sortedSet.comparator();
return (comparator == null) || comparator.equals(Ordering.natural());
}
return false;
}
public static <T> boolean isSortedSet(@Nonnull Comparator<? extends T> elementComparator,
@Nonnull Iterable<? extends T> it) {
if (it instanceof SortedSet) {
SortedSet<? extends T> sortedSet = (SortedSet<? extends T>)it;
Comparator<?> comparator = sortedSet.comparator();
if (comparator == null) {
return elementComparator.equals(Ordering.natural());
}
return elementComparator.equals(comparator);
}
return false;
}
@Nonnull
private static <T> SortedSet<? extends T> toNaturalSortedSet(@Nonnull Collection<? extends T> collection) {
if (isNaturalSortedSet(collection)) {
return (SortedSet<? extends T>)collection;
}
return ImmutableSortedSet.copyOf(collection);
}
@Nonnull
private static <T> SortedSet<? extends T> toSortedSet(@Nonnull Comparator<? super T> elementComparator,
@Nonnull Collection<? extends T> collection) {
if (collection instanceof SortedSet) {
SortedSet<? extends T> sortedSet = (SortedSet<? extends T>)collection;
Comparator<?> comparator = sortedSet.comparator();
if (comparator != null && comparator.equals(elementComparator)) {
return sortedSet;
}
}
return ImmutableSortedSet.copyOf(elementComparator, collection);
}
@Nonnull
public static <T> Comparator<Collection<? extends T>> setComparator(
@Nonnull final Comparator<? super T> elementComparator) {
return new Comparator<Collection<? extends T>>() {
@Override
public int compare(Collection<? extends T> list1, Collection<? extends T> list2) {
return compareAsSet(elementComparator, list1, list2);
}
};
}
public static <T extends Comparable<T>> int compareAsSet(@Nonnull Collection<? extends T> set1,
@Nonnull Collection<? extends T> set2) {
int res = Ints.compare(set1.size(), set2.size());
if (res != 0) return res;
SortedSet<? extends T> sortedSet1 = toNaturalSortedSet(set1);
SortedSet<? extends T> sortedSet2 = toNaturalSortedSet(set2);
Iterator<? extends T> elements2 = set2.iterator();
for (T element1: set1) {
res = element1.compareTo(elements2.next());
if (res != 0) return res;
}
return 0;
}
public static <T> int compareAsSet(@Nonnull Comparator<? super T> elementComparator,
@Nonnull Collection<? extends T> list1,
@Nonnull Collection<? extends T> list2) {
int res = Ints.compare(list1.size(), list2.size());
if (res != 0) return res;
SortedSet<? extends T> set1 = toSortedSet(elementComparator, list1);
SortedSet<? extends T> set2 = toSortedSet(elementComparator, list2);
Iterator<? extends T> elements2 = set2.iterator();
for (T element1: set1) {
res = elementComparator.compare(element1, elements2.next());
if (res != 0) return res;
}
return 0;
}
}