摘要:陳楊一靜態(tài)工廠類實(shí)現(xiàn)方式一靜態(tài)工廠類實(shí)現(xiàn)方式靜態(tài)工廠類最終由實(shí)現(xiàn)通過(guò)實(shí)現(xiàn)通過(guò)實(shí)現(xiàn)底層由實(shí)現(xiàn)是的一種具化表現(xiàn)形式使用拼接字符串二靜態(tài)工廠類常用收集器二靜態(tài)工廠類常用收集器返回一個(gè)不可修改的按照相遇的順序返回一個(gè)不可修改的無(wú)序返回
/** * @author 陳楊 */ @SpringBootTest @RunWith(SpringRunner.class) public class CollectorsDetail { private List一、靜態(tài)工廠類Collectors 實(shí)現(xiàn)方式names; private List students; private List > snames; @Before public void init() { names = Arrays.asList("Kirito", "Asuna", "Sinon", "Yuuki", "Alice"); snames = Arrays.asList(Collections.singletonList("Kirito"), Collections.singletonList("Asuna"), Collections.singletonList("Sinon"), Collections.singletonList("Yuuki"), Collections.singletonList("Alice")); students = new Students().init(); } @Test public void testCollectorsDetail() {
// 一、靜態(tài)工廠類Collectors 實(shí)現(xiàn)方式 // Collectors 靜態(tài)工廠類 最終由CollectorImpl實(shí)現(xiàn) // 1、 通過(guò)CollectorImpl實(shí)現(xiàn) // 2、 通過(guò)reducing()實(shí)現(xiàn)---> reducing()底層由CollectorImpl實(shí)現(xiàn) // Collectors.toList() 是 Collectors.toCollection()的一種具化表現(xiàn)形式 // Collectors.joining() 使用StringBuilder.append 拼接字符串二、靜態(tài)工廠類Collectors 常用收集器
// 二、靜態(tài)工廠類Collectors 常用收集器 /* 返回一個(gè)(不可修改)unmodifiable List的ArrayList 按照相遇的順序encounter order @since 10 @SuppressWarnings("unchecked") public staticCollector > toUnmodifiableList() { return new CollectorImpl<>((Supplier >) ArrayList::new, List::add, (left, right) -> { left.addAll(right); return left; }, list -> (List
)List.of(list.toArray()), CH_NOID); }*/ /* 返回一個(gè)(不可修改)unmodifiable Set的HashSet 無(wú)序 @since 10 @SuppressWarnings("unchecked") public static Collector > toUnmodifiableSet() { return new CollectorImpl<>((Supplier >) HashSet::new, Set::add, (left, right) -> { if (left.size() < right.size()) { right.addAll(left); return right; } else { left.addAll(right); return left; } }, set -> (Set )Set.of(set.toArray()), CH_UNORDERED_NOID); } */ /* 返回一個(gè)flatMapping扁平化mapper處理后 由downstream收集的 累加器處理的結(jié)果合并 單線程 @since 9 public static Collector flatMapping(Function super T, ? extends Stream extends U>> mapper, Collector super U, A, R> downstream) { BiConsumer downstreamAccumulator = downstream.accumulator(); return new CollectorImpl<>(downstream.supplier(), (r, t) -> { try (Stream extends U> result = mapper.apply(t)) { if (result != null) result.sequential().forEach(u -> downstreamAccumulator.accept(r, u)); } }, downstream.combiner(), downstream.finisher(), downstream.characteristics()); }*/ /* 對(duì)符合Predicate預(yù)期結(jié)果 進(jìn)行過(guò)濾filtering 使用downstream 收集元素 @since 9 public static Collector filtering(Predicate super T> predicate, Collector super T, A, R> downstream) { BiConsumer downstreamAccumulator = downstream.accumulator(); return new CollectorImpl<>(downstream.supplier(), (r, t) -> { if (predicate.test(t)) { downstreamAccumulator.accept(r, t); } }, downstream.combiner(), downstream.finisher(), downstream.characteristics()); }*/ /* 使用Map映射key-->keyMapper-->Key value-->valueMapper-->Value 對(duì)映射后的結(jié)果進(jìn)行組裝entrySet-->Map (unmodifiable Map) @since 10 @SuppressWarnings({"rawtypes", "unchecked"}) public static Collector > toUnmodifiableMap(Function super T, ? extends K> keyMapper, Function super T, ? extends U> valueMapper) { Objects.requireNonNull(keyMapper, "keyMapper"); Objects.requireNonNull(valueMapper, "valueMapper"); return collectingAndThen( toMap(keyMapper, valueMapper), map -> (Map )Map.ofEntries(map.entrySet().toArray(new Map.Entry[0]))); }*/ /* 使用Map映射key-->keyMapper-->Key value-->valueMapper-->Value mergeFunction 對(duì)相同key 映射后的進(jìn)行Value 合并操作 對(duì)映射后的結(jié)果進(jìn)行組裝entrySet-->Map (unmodifiable Map) @since 10 @SuppressWarnings({"rawtypes", "unchecked"}) public static Collector > toUnmodifiableMap(Function super T, ? extends K> keyMapper, Function super T, ? extends U> valueMapper, BinaryOperator mergeFunction) { Objects.requireNonNull(keyMapper, "keyMapper"); Objects.requireNonNull(valueMapper, "valueMapper"); Objects.requireNonNull(mergeFunction, "mergeFunction"); return collectingAndThen( toMap(keyMapper, valueMapper, mergeFunction, HashMap::new), map -> (Map )Map.ofEntries(map.entrySet().toArray(new Map.Entry[0]))); }*/
// Collectors 收集器 System.out.println("----------------------------------------- "); // 使用ArrayList集合 按照流中元素排列先后順序 進(jìn)行添加操作 List三、groupingBy分組unmodifiableList = names.stream().collect(Collectors.toUnmodifiableList()); System.out.println(unmodifiableList); System.out.println("--------------------------------------- "); // 使用HashSet集合 對(duì)流中元素順序 進(jìn)行添加操作 Set unmodifiableSet = names.stream().collect(Collectors.toUnmodifiableSet()); System.out.println(unmodifiableSet); System.out.println("--------------------------------------- "); // 將集合扁平化展開(kāi) 對(duì)其中的字符串的每個(gè)字母 進(jìn)行大寫轉(zhuǎn)換 使用ArrayList對(duì)轉(zhuǎn)換后的結(jié)果進(jìn)行收集 List strings = snames.stream() .collect(Collectors.flatMapping(list -> list.stream().map(String::toUpperCase), Collectors.toList())); System.out.println(strings); System.out.println("--------------------------------------- "); // 對(duì)流中元素進(jìn)行遍歷 對(duì)符合預(yù)期要求的元素 使用ArrayList集合存放 List filteringPredicate = names.stream().collect(Collectors.filtering("Kirito"::equals, Collectors.toList())); System.out.println(filteringPredicate); System.out.println("--------------------------------------- "); // 對(duì)流中元素進(jìn)行遍歷 對(duì)key-->keyMapper value-->valueMapper 映射 得到Map集合 Map > listMap = students.stream() .collect(Collectors.toUnmodifiableMap(Student::getId, student -> { List stus = new ArrayList<>(); stus.add(student); return stus; })); System.out.println(listMap); System.out.println("--------------------------------------- "); // 對(duì)流中元素進(jìn)行遍歷 對(duì)key-->keyMapper-->Key value-->valueMapper-->Value 映射 // 對(duì)滿足相同Key的元素 Value進(jìn)行合并 Map lengthName = names.stream() .collect(Collectors.toUnmodifiableMap(String::length, String::toString, (str1, str2) -> str1 + " " + str2)); System.out.println(lengthName); System.out.println("--------------------------------------- ");
// 三、groupingBy分組 // 分組 groupingBy // 對(duì)T元素按 key進(jìn)行分組 --> 分組的依據(jù) classifier--> 分組后的集合 value--> 得到 Map/* Returns a {@code Collector} implementing a "group by" operation on input elements of type {@code T}, grouping elements according to a classification function, and returning the results in a {@code Map}. The classification function maps elements to some key type {@code K}. The collector produces a {@code Map
>} whose keys are the values resulting from applying the classification function to the input elements, and whose corresponding values are {@code List}s containing the input elements which map to the associated key under the classification function. There are no guarantees on the type, mutability, serializability, or thread-safety of the {@code Map} or {@code List} objects returned.*/ /* 按照key對(duì)T進(jìn)行classifier分組 使用List集合收集分組結(jié)果 單線程 線程安全 public static
Collector >> groupingBy(Function super T, ? extends K> classifier) { return groupingBy(classifier, toList()); }*/ /* 按照key對(duì)T進(jìn)行classifier分組 使用自定義收集器downstream 收集分組結(jié)果 單線程 線程安全 public static Collector > groupingBy(Function super T, ? extends K> classifier, Collector super T, A, D> downstream) { return groupingBy(classifier, HashMap::new, downstream); }*/ /* 按照key對(duì)T進(jìn)行classifier分組 使用自定義mapFactory 重置downstream的CollectorImpl實(shí)現(xiàn) 使用自定義收集器downstream 收集分組結(jié)果 單線程 線程安全 public static > Collector groupingBy(Function super T, ? extends K> classifier, Supplier mapFactory, Collector super T, A, D> downstream) { Supplier downstreamSupplier = downstream.supplier(); BiConsumer downstreamAccumulator = downstream.accumulator(); BiConsumer
// 分組 System.out.println("----------------------------------------- "); // select * from students group by sex ; Map四、groupingByConcurrent分組> sexStudent = students.stream().collect(Collectors.groupingBy(Student::getSex)); System.out.println(sexStudent); System.out.println("----------------------------------------- "); // select sex, count(*) from students group by sex ; Map sexCount = students.stream().collect(Collectors.groupingBy(Student::getSex, Collectors.counting())); System.out.println(sexCount); System.out.println("----------------------------------------- "); // select sex,avg(salary) from students group by sex ; Map avgSexSalary = students.stream().collect (Collectors.groupingBy(Student::getSex, Collectors.averagingDouble(Student::getSalary))); System.out.println(avgSexSalary); System.out.println("----------------------------------------- "); // 嵌套分組 先根據(jù)sex分組 再對(duì)結(jié)果按照addr進(jìn)行分組 Map >> NestedGroupBy = students.stream() .collect(Collectors.groupingBy(Student::getSex, Collectors.groupingBy(Student::getAddr))); System.out.println(NestedGroupBy); System.out.println("----------------------------------------- "); // 使用自定義收集器downstream 按性別分組 使用HashSet進(jìn)行 結(jié)果收集 Map > sexHashSet = students.stream() .collect(Collectors.groupingBy(Student::getSex, Collectors.toCollection(HashSet::new))); System.out.println(sexHashSet); System.out.println("----------------------------------------- "); // 使用自定義收集器downstream 按性別分組 使用HashSet進(jìn)行 結(jié)果收集 重置CollectorImpl實(shí)現(xiàn) Map > sexCustomCollectorImpl = students.stream() .collect(Collectors.groupingBy(Student::getSex, Hashtable::new, Collectors.toCollection(HashSet::new))); System.out.println(sexCustomCollectorImpl); System.out.println("----------------------------------------- ");
// 四、groupingByConcurrent分組 // 分組 groupingByConcurrent // 流的適用條件: // 無(wú)序 Collector.Characteristics.UNORDERED // 并發(fā) Collector.Characteristics.CONCURRENT // This is a {@link Collector.Characteristics#CONCURRENT concurrent} and // {@link Collector.Characteristics#UNORDERED unordered} Collector. /* 按照key對(duì)T進(jìn)行classifier分組 使用List集合收集分組結(jié)果 public staticCollector >> groupingByConcurrent(Function super T, ? extends K> classifier) { return groupingByConcurrent(classifier, ::new, toList()); }*/ /* 按照key對(duì)T進(jìn)行classifier分組 使用自定義收集器downstream 收集分組結(jié)果 public static Collector > groupingByConcurrent(Function super T, ? extends K> classifier, Collector super T, A, D> downstream) { return groupingByConcurrent(classifier, ConcurrentHashMap::new, downstream); }*/ /* 按照key對(duì)T進(jìn)行classifier分組 使用自定義累加器mapFactory 重置downstream的CollectorImpl實(shí)現(xiàn) 使用自定義收集器downstream 收集分組結(jié)果 public static > Collector groupingByConcurrent(Function super T, ? extends K> classifier, Supplier mapFactory, Collector super T, A, D> downstream) { Supplier downstreamSupplier = downstream.supplier(); BiConsumer downstreamAccumulator = downstream.accumulator(); BinaryOperator > merger = Collectors. >mapMerger(downstream.combiner()); @SuppressWarnings("unchecked") Supplier > mangledFactory = (Supplier >) mapFactory; BiConsumer , T> accumulator; if (downstream.characteristics().contains(Collector.Characteristics.CONCURRENT)) { accumulator = (m, t) -> { K key = Objects.requireNonNull(classifier.apply(t), "element cannot be mapped to a null key"); A resultContainer = m.computeIfAbsent(key, k -> downstreamSupplier.get()); downstreamAccumulator.accept(resultContainer, t); }; } else { accumulator = (m, t) -> { K key = Objects.requireNonNull(classifier.apply(t), "element cannot be mapped to a null key"); A resultContainer = m.computeIfAbsent(key, k -> downstreamSupplier.get()); // 多個(gè)操作-->同時(shí)操作同一個(gè)結(jié)果容器-->同一時(shí)間,有且只有一個(gè)進(jìn)行實(shí)際操作-->線程同步 synchronized (resultContainer) { downstreamAccumulator.accept(resultContainer, t); } }; } if (downstream.characteristics().contains(Collector.Characteristics.IDENTITY_FINISH)) { return new CollectorImpl<>(mangledFactory, accumulator, merger, CH_CONCURRENT_ID); } else { @SuppressWarnings("unchecked") Function downstreamFinisher = (Function) downstream.finisher(); Function , M> finisher = intermediate -> { intermediate.replaceAll((k, v) -> downstreamFinisher.apply(v)); @SuppressWarnings("unchecked") M castResult = (M) intermediate; return castResult; }; return new CollectorImpl<>(mangledFactory, accumulator, merger, finisher, CH_CONCURRENT_NOID); } }*/
// 分組 無(wú)序 并發(fā) System.out.println("----------------------------------------- "); // 按性別分組 使用ArrayList進(jìn)行 結(jié)果收集 ConcurrentMap五、partitioningBy分區(qū)> sexStudentConcurrent = students.stream() .collect(Collectors.groupingByConcurrent(Student::getSex)); System.out.println(sexStudentConcurrent); System.out.println("----------------------------------------- "); // 使用自定義收集器downstream 按性別分組 使用HashSet進(jìn)行 結(jié)果收集 ConcurrentMap > sexHashSetConcurrent = students.stream() .collect(Collectors.groupingByConcurrent(Student::getSex, Collectors.toCollection(HashSet::new))); System.out.println(sexHashSetConcurrent); System.out.println("----------------------------------------- "); // 使用自定義收集器downstream 按性別分組 使用HashSet進(jìn)行 結(jié)果收集 重置CollectorImpl實(shí)現(xiàn) ConcurrentReferenceHashMap > sexCustomCollectorImplConcurrent = students.stream().collect(Collectors.groupingByConcurrent(Student::getSex, ConcurrentReferenceHashMap::new, Collectors.toCollection(HashSet::new))); System.out.println(sexCustomCollectorImplConcurrent); System.out.println("----------------------------------------- ");
// 五、partitioningBy分區(qū) // 分區(qū) partitioningBy /* 對(duì)滿足預(yù)期的條件 進(jìn)行分區(qū) 使用ArrayList 進(jìn)行結(jié)果的收集 public staticCollector >> partitioningBy(Predicate super T> predicate) { return partitioningBy(predicate, toList()); }*/ /* 對(duì)滿足預(yù)期的條件 進(jìn)行分區(qū) 使用自定義收集器downstream 進(jìn)行結(jié)果的收集 public static Collector > partitioningBy(Predicate super T> predicate, Collector super T, A, D> downstream) { BiConsumer downstreamAccumulator = downstream.accumulator(); BiConsumer , T> accumulator = (result, t) -> downstreamAccumulator.accept(predicate.test(t) ? result.forTrue : result.forFalse, t); BinaryOperator op = downstream.combiner(); BinaryOperator > merger = (left, right) -> new Partition<>(op.apply(left.forTrue, right.forTrue), op.apply(left.forFalse, right.forFalse)); Supplier > supplier = () -> new Partition<>(downstream.supplier().get(), downstream.supplier().get()); if (downstream.characteristics().contains(Collector.Characteristics.IDENTITY_FINISH)) { return new CollectorImpl<>(supplier, accumulator, merger, CH_ID); } else { Function , Map > finisher = par -> new Partition<>(downstream.finisher().apply(par.forTrue), downstream.finisher().apply(par.forFalse)); return new CollectorImpl<>(supplier, accumulator, merger, finisher, CH_NOID); } }*/
// 分區(qū) System.out.println("----------------------------------------- "); // select * from students partition by (addr == Sword Art Online) ; Map六、測(cè)試結(jié)果> addrPartition = students.stream().collect (Collectors.partitioningBy(student -> student.getAddr().equals("Sword Art Online"))); System.out.println(addrPartition); System.out.println("----------------------------------------- "); // 嵌套分區(qū) 先根據(jù)sex分區(qū) 再對(duì)結(jié)果按照addr進(jìn)行分區(qū) Map >> NestedPartiton = students.stream() .collect(Collectors.partitioningBy(student -> student.getSex().equals("Male"), Collectors.partitioningBy(student -> student.getAddr().equals("Sword Art Online")))); System.out.println(NestedPartiton); System.out.println("----------------------------------------- "); // 使用自定義downstream收集器分區(qū) Map > addrCustomPartition = students.stream().collect(Collectors.partitioningBy (student -> student.getAddr().equals("Sword Art Online"), Collectors.toCollection(HashSet::new))); System.out.println(addrCustomPartition); System.out.println("----------------------------------------- "); } }
. ____ _ __ _ _ / / ___"_ __ _ _(_)_ __ __ _ ( ( )\___ | "_ | "_| | "_ / _` | / ___)| |_)| | | | | || (_| | ) ) ) ) " |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot :: (v2.1.2.RELEASE) 2019-02-20 16:58:15.870 INFO 13392 --- [ main] c.j.d.java8.Stream.CollectorsDetail : Starting CollectorsDetail on DESKTOP-87RMBG4 with PID 13392 (started by 46250 in E:IdeaProjectsdesign) 2019-02-20 16:58:15.871 INFO 13392 --- [ main] c.j.d.java8.Stream.CollectorsDetail : No active profile set, falling back to default profiles: default 2019-02-20 16:58:16.383 INFO 13392 --- [ main] c.j.d.java8.Stream.CollectorsDetail : Started CollectorsDetail in 0.708 seconds (JVM running for 1.421) ----------------------------------------- [Kirito, Asuna, Sinon, Yuuki, Alice] --------------------------------------- [Yuuki, Asuna, Kirito, Sinon, Alice] --------------------------------------- [KIRITO, ASUNA, SINON, YUUKI, ALICE] --------------------------------------- [Kirito] --------------------------------------- {5=[Student(id=5, name=Alice, sex=Female, age=14, addr=Alicization, salary=9.99999999E8)], 4=[Student(id=4, name=Yuuki, sex=Female, age=15, addr=Alfheim Online, salary=9.99999999E8)], 3=[Student(id=3, name=Sinon, sex=Female, age=16, addr=Gun Gale Online, salary=9.99999999E8)], 2=[Student(id=2, name=Asuna, sex=Female, age=17, addr=Sword Art Online, salary=9.99999999E8)], 1=[Student(id=1, name=Kirito, sex=Male, age=18, addr=Sword Art Online, salary=9.99999999E8)]} --------------------------------------- {6=Kirito, 5=Asuna Sinon Yuuki Alice} --------------------------------------- ----------------------------------------- {Female=[Student(id=2, name=Asuna, sex=Female, age=17, addr=Sword Art Online, salary=9.99999999E8), Student(id=3, name=Sinon, sex=Female, age=16, addr=Gun Gale Online, salary=9.99999999E8), Student(id=4, name=Yuuki, sex=Female, age=15, addr=Alfheim Online, salary=9.99999999E8), Student(id=5, name=Alice, sex=Female, age=14, addr=Alicization, salary=9.99999999E8)], Male=[Student(id=1, name=Kirito, sex=Male, age=18, addr=Sword Art Online, salary=9.99999999E8)]} ----------------------------------------- {Female=4, Male=1} ----------------------------------------- {Female=9.99999999E8, Male=9.99999999E8} ----------------------------------------- {Female={Alicization=[Student(id=5, name=Alice, sex=Female, age=14, addr=Alicization, salary=9.99999999E8)], Sword Art Online=[Student(id=2, name=Asuna, sex=Female, age=17, addr=Sword Art Online, salary=9.99999999E8)], Gun Gale Online=[Student(id=3, name=Sinon, sex=Female, age=16, addr=Gun Gale Online, salary=9.99999999E8)], Alfheim Online=[Student(id=4, name=Yuuki, sex=Female, age=15, addr=Alfheim Online, salary=9.99999999E8)]}, Male={Sword Art Online=[Student(id=1, name=Kirito, sex=Male, age=18, addr=Sword Art Online, salary=9.99999999E8)]}} ----------------------------------------- {Female=[Student(id=4, name=Yuuki, sex=Female, age=15, addr=Alfheim Online, salary=9.99999999E8), Student(id=3, name=Sinon, sex=Female, age=16, addr=Gun Gale Online, salary=9.99999999E8), Student(id=5, name=Alice, sex=Female, age=14, addr=Alicization, salary=9.99999999E8), Student(id=2, name=Asuna, sex=Female, age=17, addr=Sword Art Online, salary=9.99999999E8)], Male=[Student(id=1, name=Kirito, sex=Male, age=18, addr=Sword Art Online, salary=9.99999999E8)]} ----------------------------------------- {Female=[Student(id=4, name=Yuuki, sex=Female, age=15, addr=Alfheim Online, salary=9.99999999E8), Student(id=3, name=Sinon, sex=Female, age=16, addr=Gun Gale Online, salary=9.99999999E8), Student(id=5, name=Alice, sex=Female, age=14, addr=Alicization, salary=9.99999999E8), Student(id=2, name=Asuna, sex=Female, age=17, addr=Sword Art Online, salary=9.99999999E8)], Male=[Student(id=1, name=Kirito, sex=Male, age=18, addr=Sword Art Online, salary=9.99999999E8)]} ----------------------------------------- ----------------------------------------- {Male=[Student(id=1, name=Kirito, sex=Male, age=18, addr=Sword Art Online, salary=9.99999999E8)], Female=[Student(id=2, name=Asuna, sex=Female, age=17, addr=Sword Art Online, salary=9.99999999E8), Student(id=3, name=Sinon, sex=Female, age=16, addr=Gun Gale Online, salary=9.99999999E8), Student(id=4, name=Yuuki, sex=Female, age=15, addr=Alfheim Online, salary=9.99999999E8), Student(id=5, name=Alice, sex=Female, age=14, addr=Alicization, salary=9.99999999E8)]} ----------------------------------------- {Male=[Student(id=1, name=Kirito, sex=Male, age=18, addr=Sword Art Online, salary=9.99999999E8)], Female=[Student(id=4, name=Yuuki, sex=Female, age=15, addr=Alfheim Online, salary=9.99999999E8), Student(id=3, name=Sinon, sex=Female, age=16, addr=Gun Gale Online, salary=9.99999999E8), Student(id=5, name=Alice, sex=Female, age=14, addr=Alicization, salary=9.99999999E8), Student(id=2, name=Asuna, sex=Female, age=17, addr=Sword Art Online, salary=9.99999999E8)]} ----------------------------------------- {Female=[Student(id=4, name=Yuuki, sex=Female, age=15, addr=Alfheim Online, salary=9.99999999E8), Student(id=3, name=Sinon, sex=Female, age=16, addr=Gun Gale Online, salary=9.99999999E8), Student(id=5, name=Alice, sex=Female, age=14, addr=Alicization, salary=9.99999999E8), Student(id=2, name=Asuna, sex=Female, age=17, addr=Sword Art Online, salary=9.99999999E8)], Male=[Student(id=1, name=Kirito, sex=Male, age=18, addr=Sword Art Online, salary=9.99999999E8)]} ----------------------------------------- ----------------------------------------- {false=[Student(id=3, name=Sinon, sex=Female, age=16, addr=Gun Gale Online, salary=9.99999999E8), Student(id=4, name=Yuuki, sex=Female, age=15, addr=Alfheim Online, salary=9.99999999E8), Student(id=5, name=Alice, sex=Female, age=14, addr=Alicization, salary=9.99999999E8)], true=[Student(id=1, name=Kirito, sex=Male, age=18, addr=Sword Art Online, salary=9.99999999E8), Student(id=2, name=Asuna, sex=Female, age=17, addr=Sword Art Online, salary=9.99999999E8)]} ----------------------------------------- {false={false=[Student(id=3, name=Sinon, sex=Female, age=16, addr=Gun Gale Online, salary=9.99999999E8), Student(id=4, name=Yuuki, sex=Female, age=15, addr=Alfheim Online, salary=9.99999999E8), Student(id=5, name=Alice, sex=Female, age=14, addr=Alicization, salary=9.99999999E8)], true=[Student(id=2, name=Asuna, sex=Female, age=17, addr=Sword Art Online, salary=9.99999999E8)]}, true={false=[], true=[Student(id=1, name=Kirito, sex=Male, age=18, addr=Sword Art Online, salary=9.99999999E8)]}} ----------------------------------------- {false=[Student(id=4, name=Yuuki, sex=Female, age=15, addr=Alfheim Online, salary=9.99999999E8), Student(id=3, name=Sinon, sex=Female, age=16, addr=Gun Gale Online, salary=9.99999999E8), Student(id=5, name=Alice, sex=Female, age=14, addr=Alicization, salary=9.99999999E8)], true=[Student(id=2, name=Asuna, sex=Female, age=17, addr=Sword Art Online, salary=9.99999999E8), Student(id=1, name=Kirito, sex=Male, age=18, addr=Sword Art Online, salary=9.99999999E8)]} -----------------------------------------
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