現在有一個實體類Person,屬性有三個,分別是name,age,address,根據這三個屬性將list<Person>中三個字段都相同的數據進行去重。
//創建list,添加數據
List<Person> list = new ArrayList<>();
list.add(new Person("Tom", 15, "America"));
list.add(new Person("Tam", 16, "China"));
list.add(new Person("Tom", 15, "Japan"));
list.add(new Person("Tcm", 18, "Russia"));
list.add(new Person("Tom", 15, "America"));
list.add(new Person("Tdm", 16, "America"));
list.add(new Person("Tem", 17, "America"));
// 根據三個字段去重
List<Person> lst = list.stream().collect(Collectors.collectingAndThen(Collectors.toCollection(
() -> new TreeSet<>(Comparator.comparing(o -> o.getName() + "#" + o.getAge() + "#" + o.getAddress()))),
ArrayList::new));
// 遍歷輸出一下
lst.forEach(person -> System.out.println(person.toString()));
//結果:
Person [name=Tam, age=16, address=China]
Person [name=Tcm, age=18, address=Russia]
Person [name=Tdm, age=16, address=America]
Person [name=Tem, age=17, address=America]
Person [name=Tom, age=15, address=America]
Person [name=Tom, age=15, address=Japan]