com.google.common.collect.CartesianList Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* Copyright (C) 2012 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;
import static com.google.common.base.Preconditions.checkElementIndex;
import com.google.common.annotations.GwtCompatible;
import com.google.common.math.IntMath;
import java.util.AbstractList;
import java.util.List;
import java.util.ListIterator;
import java.util.RandomAccess;
import javax.annotation.CheckForNull;
/**
* Implementation of {@link Lists#cartesianProduct(List)}.
*
* @author Louis Wasserman
*/
@GwtCompatible
@ElementTypesAreNonnullByDefault
final class CartesianList extends AbstractList> implements RandomAccess {
private final transient ImmutableList> axes;
private final transient int[] axesSizeProduct;
static List> create(List> lists) {
ImmutableList.Builder> axesBuilder = new ImmutableList.Builder<>(lists.size());
for (List list : lists) {
List copy = ImmutableList.copyOf(list);
if (copy.isEmpty()) {
return ImmutableList.of();
}
axesBuilder.add(copy);
}
return new CartesianList<>(axesBuilder.build());
}
CartesianList(ImmutableList> axes) {
this.axes = axes;
int[] axesSizeProduct = new int[axes.size() + 1];
axesSizeProduct[axes.size()] = 1;
try {
for (int i = axes.size() - 1; i >= 0; i--) {
axesSizeProduct[i] = IntMath.checkedMultiply(axesSizeProduct[i + 1], axes.get(i).size());
}
} catch (ArithmeticException e) {
throw new IllegalArgumentException(
"Cartesian product too large; must have size at most Integer.MAX_VALUE");
}
this.axesSizeProduct = axesSizeProduct;
}
private int getAxisIndexForProductIndex(int index, int axis) {
return (index / axesSizeProduct[axis + 1]) % axes.get(axis).size();
}
@Override
public int indexOf(@CheckForNull Object o) {
if (!(o instanceof List)) {
return -1;
}
List list = (List) o;
if (list.size() != axes.size()) {
return -1;
}
ListIterator itr = list.listIterator();
int computedIndex = 0;
while (itr.hasNext()) {
int axisIndex = itr.nextIndex();
int elemIndex = axes.get(axisIndex).indexOf(itr.next());
if (elemIndex == -1) {
return -1;
}
computedIndex += elemIndex * axesSizeProduct[axisIndex + 1];
}
return computedIndex;
}
@Override
public int lastIndexOf(@CheckForNull Object o) {
if (!(o instanceof List)) {
return -1;
}
List list = (List) o;
if (list.size() != axes.size()) {
return -1;
}
ListIterator itr = list.listIterator();
int computedIndex = 0;
while (itr.hasNext()) {
int axisIndex = itr.nextIndex();
int elemIndex = axes.get(axisIndex).lastIndexOf(itr.next());
if (elemIndex == -1) {
return -1;
}
computedIndex += elemIndex * axesSizeProduct[axisIndex + 1];
}
return computedIndex;
}
@Override
public ImmutableList get(int index) {
checkElementIndex(index, size());
return new ImmutableList() {
@Override
public int size() {
return axes.size();
}
@Override
public E get(int axis) {
checkElementIndex(axis, size());
int axisIndex = getAxisIndexForProductIndex(index, axis);
return axes.get(axis).get(axisIndex);
}
@Override
boolean isPartialView() {
return true;
}
};
}
@Override
public int size() {
return axesSizeProduct[0];
}
@Override
public boolean contains(@CheckForNull Object object) {
if (!(object instanceof List)) {
return false;
}
List list = (List) object;
if (list.size() != axes.size()) {
return false;
}
int i = 0;
for (Object o : list) {
if (!axes.get(i).contains(o)) {
return false;
}
i++;
}
return true;
}
}