public void filterMapByKeyGuava () { Map<Integer, String> map = Maps.filterKeys(WEEK, r -> r <= 3); assertThat(map.keySet(), contains(1, 2, 3)); } } filter by value public class FilterMapByValueTest { private Map<Integer, String> WEEK = new HashMap<>(); @Before public void...
filter by value publicclassFilterMapByValueTest{privateMap<Integer,String>WEEK=newHashMap<>();@BeforepublicvoidsetUp () {WEEK.put(1,"Monday");WEEK.put(2,"Tuesday");WEEK.put(3,"Wednesday");WEEK.put(4,"Thursday");WEEK.put(5,"Friday");WEEK.put(6,"Saturday");WEEK.put(7,"Sunday"); ...
importjava.util.stream.Collectors;// 定义过滤的方法publicstaticMap<String,Integer>filterMap(Map<String,Integer>map,intthreshold){// 使用 Stream API 过滤 Mapreturnmap.entrySet()// 获取 Map 的条目集.stream()// 将条目集转化为流.filter(entry->entry.getValue()>threshold)// 过滤条件.collect(Collec...
public void filterMapByKeyJava8Lambda () { Mapmap = WEEK.entrySet().stream().filter(r -> r.getKey() <= 3) .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue)); assertThat(map.keySet(), contains(1, 2, 3)); ...
Map<String,Integer>filteredMap=filteredStream.collect(Collectors.toMap(Map.Entry::getKey,Map.Entry::getValue)); 1. 7. 完整代码示例 下面是一个完整的Java Map Filter的代码示例: AI检测代码解析 importjava.util.HashMap;importjava.util.Map;importjava.util.stream.Collectors;importjava.util.stream.Stream...
.filter(user-> user.getId() <10) .map(user-> user.getUsername()); 8、or 方法的作用是,如果一个 Optional 包含值,则返回自己;否则返回由参数 supplier 获得的 Optional 9、ifPresentOrElse 方法的用途是,如果一个 Optional 包含值,则对其包含的值调用函数 action,即 action.accept(value),这与 ifPresent...
filter(user -> user.getAge() != null && user.getAge() >= 30).map(User::getName).collect(Collectors.toList()); System.out.println(list); 以上代码是求出User的age大于等于30的name并收集成List,打印。 在上面的例子,collect是个终端操作,执行后关闭流。users.stream()创建了ReferencePipeline....
filter by value publicclassFilterMapByValueTest{privateMap<Integer,String>WEEK=newHashMap<>();@BeforepublicvoidsetUp(){WEEK.put(1,"Monday");WEEK.put(2,"Tuesday");WEEK.put(3,"Wednesday");WEEK.put(4,"Thursday");WEEK.put(5,"Friday");WEEK.put(6,"Saturday");WEEK.put(7,"Sunday");}/*...
map()函数是Stream类中的一个方法,它表示函数式编程概念。简单来说,map()通过应用于函数将一个对象转换为另一个对象。这就是Stream.map(函数映射器)将函数作为参数的原因。例如,通过使用map()函数,您可以通过将Integer.valueOf()方法应用于输入列表上的每个String,将String列表转换为List of Integer。 您只需要一...
public void filterMapByKeyJava8Lambda () { Map<Integer, String> map = WEEK.entrySet().stream().filter(r -> r.getKey() <= 3).collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));assertThat(map.keySet(), contains(1, 2, 3));} /** * Google Guava */ @Test public ...