springboot webflux flux 使用示例（转换操作）

叁歲伎倆 2023-02-20 13:44 58阅读 0赞

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### springboot webflux flux 使用示例（转换操作） ###

### \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* ###

**flatMap、map、transform、switchMap**

class Person{
    
        private String name;
        private Integer age;
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public Integer getAge() {
            return age;
        }
    
        public void setAge(Integer age) {
            this.age = age;
        }
    
        @Override
        public boolean equals(Object o) {
            if (this == o) return true;
            if (!(o instanceof Person)) return false;
            Person person = (Person) o;
            return Objects.equals(getName(), person.getName()) &&
                    Objects.equals(getAge(), person.getAge());
        }
    
        @Override
        public int hashCode() {
            return Objects.hash(getName(), getAge());
        }
    
        @Override
        public String toString() {
            return "Person{" +
                    "name='" + name + '\'' +
                    ", age=" + age +
                    '}';
        }
    }
    
    public class Test {
    
        public static void main(String[] args){
            Map<String,String> map=new HashMap<>();
            map.put("name","瓜田李下");
            map.put("age","20");
    
            Flux.just(map).flatMap(m -> {
                String name=m.get("name");
                Integer age=Integer.parseInt(m.get("age"));
    
                Person person=new Person();
                person.setName(name);
                person.setAge(age);
    
                return Flux.just(person);
            }).subscribe(System.out::println);
    
            Flux.just(map).map(m -> {
                String name=m.get("name");
                Integer age=Integer.parseInt(m.get("age"));
    
                Person person=new Person();
                person.setName(name);
                person.setAge(age);
    
                return person;
            }).subscribe(System.out::println);
    
            Flux.just(map).transform(flux -> flux.flatMap(m -> {
                String name=m.get("name");
                Integer age=Integer.parseInt(m.get("age"));
    
                Person person=new Person();
                person.setName(name);
                person.setAge(age);
    
                return Flux.just(person);
            })).subscribe(System.out::println);
    
            Flux.just(map).transform(flux -> flux.map(m -> {
                String name=m.get("name");
                Integer age=Integer.parseInt(m.get("age"));
    
                Person person=new Person();
                person.setName(name);
                person.setAge(age);
    
                return person;
            })).subscribe(System.out::println);
    
            Flux.just(map).switchMap(m -> {
                String name=m.get("name");
                Integer age=Integer.parseInt(m.get("age"));
    
                Person person=new Person();
                person.setName(name);
                person.setAge(age);
    
                return Flux.just(person);
            }).subscribe(System.out::println);
        }
    }

**\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\***

**控制台输出**

Person{name='瓜田李下', age=20}
    Person{name='瓜田李下', age=20}
    Person{name='瓜田李下', age=20}
    Person{name='瓜田李下', age=20}
    Person{name='瓜田李下', age=20}

### \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* ###

**toIterable、toStream**

public class Test2 {
    
        public static void main(String[] args){
            Flux.just("瓜田李下","瓜田李下 2","瓜田李下 3","瓜田李下 4","瓜田李下 5","瓜田李下 6")
                    .toIterable().forEach(System.out::println);
    
            Flux.just("1 ","2 ","3 ","4 ","5 ","6 ").toStream().forEach(System.out::print);
    
            System.out.println("\n\n************");
            String s=Flux.just("瓜田李下","瓜田李下 2").elementAt(0)
                    .flux().toIterable().iterator().next();
            System.out.println("flux 第0个元素为："+s);
    
            String s2=Flux.just("hello world","hello world 2","hello world 3").last()
                    .flux().toIterable().iterator().next();
            System.out.println("flux 最后一个元素为："+s2);
        }
    }

**\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\***

**控制台输出**

瓜田李下
    瓜田李下 2
    瓜田李下 3
    瓜田李下 4
    瓜田李下 5
    瓜田李下 6
    1 2 3 4 5 6 
    
    ************
    flux 第0个元素为：瓜田李下
    flux 最后一个元素为：hello world 3

### \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* ###

**collect **

public class Test3 {
    
        public static void main(String[] args){
            Flux.just(2,34,56,75,4,56).collectList()
                    .subscribe(list -> list.forEach(value -> System.out.print(value+"  ")));
    
            System.out.println();
            Flux.just(2,34,56,75,4,56).collectSortedList()
                    .subscribe(list -> list.forEach(value -> System.out.print(value+"  ")));
    
            System.out.println("\n\n****************");
            Flux.just("1 瓜田李下","2 瓜田李下2","3 瓜田李下3").collectMap(
                    value -> {
                        String[] s= value.split(" ");
                        return s[0];
                    },
                    value -> {
                        String[] s= value.split(" ");
                        return s[1];
                    }
            ).subscribe(map -> map.forEach((key, value1) -> System.out.println(key + "  " + value1)));
    
            System.out.println("\n****************");
            Flux.just("1 瓜田李下 瓜田李下2 瓜田李下3 瓜田李下4 瓜田李下5 瓜田李下6",
                    "2 hello hello2 hello3 hello4 hello5 hello6")
                    .collectMultimap(
                            value -> {
                                String[] s=value.split(" ");
                                return s[0];
                                },
                            value -> {
                                String[] s=value.split(" ");
    
                                List<String> list=new ArrayList<>();
                                if (s.length>1) {
                                    list.addAll(Arrays.asList(s).subList(1, s.length));
                                }
    
                                return list;
                            }).subscribe(map -> map.forEach((key,value) -> System.out.println(key+"  "+value)));
        }
    }

**\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\***

**控制台输出**

2  34  56  75  4  56  
    2  4  34  56  56  75  
    
    ****************
    1  瓜田李下
    2  瓜田李下2
    3  瓜田李下3
    
    ****************
    1  [[瓜田李下, 瓜田李下2, 瓜田李下3, 瓜田李下4, 瓜田李下5, 瓜田李下6]]
    2  [[hello, hello2, hello3, hello4, hello5, hello6]]