优化IndexedComparator性能

This commit is contained in:
Looly 2024-07-30 11:20:56 +08:00
parent 3dd473b2c4
commit fcd0d004e3
5 changed files with 200 additions and 16 deletions

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@ -0,0 +1,85 @@
/*
* Copyright (c) 2023 looly(loolly@aliyun.com)
* Hutool is licensed under Mulan PSL v2.
* You can use this software according to the terms and conditions of the Mulan PSL v2.
* You may obtain a copy of Mulan PSL v2 at:
* https://license.coscl.org.cn/MulanPSL2
* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
* See the Mulan PSL v2 for more details.
*/
package org.dromara.hutool.core.comparator;
import org.dromara.hutool.core.lang.Assert;
import org.dromara.hutool.core.array.ArrayUtil;
import java.util.Comparator;
/**
* 按照数组的顺序正序排列数组的元素位置决定了对象的排序先后<br>
* 默认的如果参与排序的元素并不在数组中则排序在前可以通过atEndIfMiss设置)
*
* @param <T> 被排序元素类型
* @author looly
* @since 4.1.5
*/
public class ArrayIndexedComparator<T> implements Comparator<T> {
private final boolean atEndIfMiss;
private final T[] array;
/**
* 构造
*
* @param objs 参与排序的数组数组的元素位置决定了对象的排序先后
*/
@SuppressWarnings("unchecked")
public ArrayIndexedComparator(final T... objs) {
this(false, objs);
}
/**
* 构造
*
* @param atEndIfMiss 如果不在列表中是否排在后边
* @param objs 参与排序的数组数组的元素位置决定了对象的排序先后
*/
@SuppressWarnings("unchecked")
public ArrayIndexedComparator(final boolean atEndIfMiss, final T... objs) {
Assert.notNull(objs, "'objs' array must not be null");
this.atEndIfMiss = atEndIfMiss;
this.array = objs;
}
@Override
public int compare(final T o1, final T o2) {
final int index1 = getOrder(o1);
final int index2 = getOrder(o2);
// 任意一个元素不在列表中
if(index1 == index2){
if(index1 < 0 || index1 == this.array.length){
// 任意一个元素不在列表中, 返回原顺序
return 1;
}
}
return Integer.compare(index1, index2);
}
/**
* 查找对象类型所在列表的位置
*
* @param object 对象
* @return 位置未找到位置根据{@link #atEndIfMiss}取不同值false返回-1否则返回列表长度
*/
private int getOrder(final T object) {
int order = ArrayUtil.indexOf(array, object);
if (order < 0) {
order = this.atEndIfMiss ? this.array.length : -1;
}
return order;
}
}

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@ -335,7 +335,7 @@ public class CompareUtil {
@SuppressWarnings("unchecked")
public static <T, U> Comparator<T> comparingIndexed(final Function<? super T, ? extends U> keyExtractor, final boolean atEndIfMiss, final U... objs) {
Objects.requireNonNull(keyExtractor);
final IndexedComparator<U> indexedComparator = new IndexedComparator<>(atEndIfMiss, objs);
final ArrayIndexedComparator<U> indexedComparator = new ArrayIndexedComparator<>(atEndIfMiss, objs);
return (o1, o2) -> indexedComparator.compare(keyExtractor.apply(o1), keyExtractor.apply(o2));
}

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@ -1,5 +1,5 @@
/*
* Copyright (c) 2023 looly(loolly@aliyun.com)
* Copyright (c) 2024. looly(loolly@aliyun.com)
* Hutool is licensed under Mulan PSL v2.
* You can use this software according to the terms and conditions of the Mulan PSL v2.
* You may obtain a copy of Mulan PSL v2 at:
@ -13,9 +13,10 @@
package org.dromara.hutool.core.comparator;
import org.dromara.hutool.core.lang.Assert;
import org.dromara.hutool.core.array.ArrayUtil;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Map;
/**
* 按照数组的顺序正序排列数组的元素位置决定了对象的排序先后<br>
@ -28,7 +29,10 @@ import java.util.Comparator;
public class IndexedComparator<T> implements Comparator<T> {
private final boolean atEndIfMiss;
private final T[] array;
/**
* map存储对象类型所在列表的位置,k为对象v为位置
*/
private final Map<? super T, Integer> map;
/**
* 构造
@ -40,6 +44,18 @@ public class IndexedComparator<T> implements Comparator<T> {
this(false, objs);
}
/**
* 构造
*
* @param atEndIfMiss 如果不在列表中是否排在后边
* @param map 参与排序的mapmap中的value值大小决定了对象的排序先后
*/
public IndexedComparator(final boolean atEndIfMiss, final Map<? super T, Integer> map) {
this.atEndIfMiss = atEndIfMiss;
this.map = map;
}
/**
* 构造
*
@ -50,7 +66,10 @@ public class IndexedComparator<T> implements Comparator<T> {
public IndexedComparator(final boolean atEndIfMiss, final T... objs) {
Assert.notNull(objs, "'objs' array must not be null");
this.atEndIfMiss = atEndIfMiss;
this.array = objs;
map = new HashMap<>(objs.length, 1);
for (int i = 0; i < objs.length; i++) {
map.put(objs[i], i);
}
}
@Override
@ -58,27 +77,29 @@ public class IndexedComparator<T> implements Comparator<T> {
final int index1 = getOrder(o1);
final int index2 = getOrder(o2);
// 任意一个元素不在列表中
if(index1 == index2){
if(index1 < 0 || index1 == this.array.length){
// 任意一个元素不在列表中, 返回原顺序
if (index1 == index2) {
if (index1 < 0 || index1 == this.map.size()) {
// 任意一个元素不在map中, 返回原顺序
return 1;
}
// 位置一样认为是同一个元素
return 0;
}
return Integer.compare(index1, index2);
}
/**
* 查找对象类型所在列表的位置
* 查找对象类型所对应的顺序值,即在原列表中的顺序
*
* @param object 对象
* @return 位置未找到位置根据{@link #atEndIfMiss}取不同值false返回-1否则返回列表长度
* @return 位置未找到位置根据{@link #atEndIfMiss}取不同值false返回-1否则返回map长度
*/
private int getOrder(final T object) {
int order = ArrayUtil.indexOf(array, object);
if (order < 0) {
order = this.atEndIfMiss ? this.array.length : -1;
Integer order = map.get(object);
if (order == null) {
order = this.atEndIfMiss ? this.map.size() : -1;
}
return order;
}

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@ -0,0 +1,78 @@
package org.dromara.hutool.core.comparator;
import lombok.AllArgsConstructor;
import lombok.Data;
import org.dromara.hutool.core.collection.CollUtil;
import org.dromara.hutool.core.date.StopWatch;
import org.dromara.hutool.core.lang.Console;
import org.junit.jupiter.api.Disabled;
import org.junit.jupiter.api.Test;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import static org.junit.jupiter.api.Assertions.*;
/**
* https://gitee.com/dromara/hutool/pulls/1240
*/
public class IndexedComparatorTest {
@Test
public void sortTest() {
final Object[] arr = {"a", "b", new User("9", null), "1", 3, null, "2"};
final Collection<Object> set = new HashSet<>(Arrays.asList(arr));
final List<Object> sortSet = CollUtil.sort(set, new ArrayIndexedComparator<>(arr));
assertEquals("a", sortSet.get(0));
assertEquals(new User("9", null), sortSet.get(2));
assertEquals(3, sortSet.get(4));
assertNull(sortSet.get(5));
}
@Test
public void reversedTest() {
final Object[] arr = {"a", "b", new User("9", null), "1", 3, null, "2"};
final Collection<Object> set = new HashSet<>(Arrays.asList(arr));
final List<Object> sortSet = CollUtil.sort(set, new ArrayIndexedComparator<>(arr).reversed());
assertEquals("a", sortSet.get(6));
assertNull(sortSet.get(1));
assertEquals(new User("9", null), sortSet.get(4));
assertEquals(3, sortSet.get(2));
}
@Test
@Disabled
public void benchmarkSortTest() {
final Object[] arr = {"a", "b", new User("9", null), "1", 3, null, "2"};
final Collection<Object> set = new HashSet<>(Arrays.asList(arr));
final StopWatch stopWatch = new StopWatch();
stopWatch.start();
for (int i = 0; i < 10_000_000; i++) {
CollUtil.sort(set, new IndexedComparator<>(arr));
}
stopWatch.stop();
stopWatch.start();
for (int i = 0; i < 10_000_000; i++) {
CollUtil.sort(set, new ArrayIndexedComparator<>(arr));
}
stopWatch.stop();
Console.log(stopWatch.prettyPrint());
}
@Data
@AllArgsConstructor
static class User {
private String a;
private String b;
}
}

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@ -22,7 +22,7 @@ import org.apache.poi.xssf.usermodel.XSSFDataValidation;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.dromara.hutool.core.bean.BeanUtil;
import org.dromara.hutool.core.collection.ListUtil;
import org.dromara.hutool.core.comparator.IndexedComparator;
import org.dromara.hutool.core.comparator.ArrayIndexedComparator;
import org.dromara.hutool.core.io.IORuntimeException;
import org.dromara.hutool.core.io.IoUtil;
import org.dromara.hutool.core.io.file.FileUtil;
@ -1440,7 +1440,7 @@ public class ExcelWriter extends ExcelBase<ExcelWriter> {
Comparator<String> aliasComparator = this.aliasComparator;
if (null == aliasComparator) {
final Set<String> keySet = this.headerAlias.keySet();
aliasComparator = new IndexedComparator<>(keySet.toArray(new String[0]));
aliasComparator = new ArrayIndexedComparator<>(keySet.toArray(new String[0]));
this.aliasComparator = aliasComparator;
}
return aliasComparator;