Guava系列：FluentIterable使用方法（List条件过滤）

目录

​​场景​​

​​demo​​

场景

list集合过滤数据

demo

package com.nio4444.demo;

import com.google.common.base.Function;
import com.google.common.base.Joiner;
import com.google.common.base.Predicate;
import com.google.common.collect.FluentIterable;
import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
import lombok.Data;
import lombok.RequiredArgsConstructor;

import java.util.List;

public class FluentIterableDemo {
    public static void main(String[] args) {
        Person p1 = new Person("12",1) ;
        Person p2 = new Person("22",2) ;
        Person p3 = new Person("32",3) ;


        List perList = Lists.newArrayList(p1,p2,p3);

        /**
         * filter
         */
        Iterable<Person> it = FluentIterable.from(perList).filter(new Predicate<Person>() {
                @Override
                public boolean apply(Person p) {
                    return p.age>1;
                }
            });
        System.out.println( Iterables.contains(it,p1));//false
        System.out.println( Iterables.contains(it,p2));//true
        System.out.println( Iterables.contains(it,p3));//true

        /**
         * transform: Person-> String
         */
        FluentIterable fluentIterablen =FluentIterable.from(perList).transform(new Function<Person,String>() {
            @Override
            public String apply(Person p) {
                return Joiner.on("#").join(p.name,p.age);
            }
        })  ;

        System.out.println(fluentIterablen.toList()); //[12#1, 22#2, 32#3]




    }

    static class Person{
        String name ;
        int age ;
        Person(String name,int age){
            this.age=age;
            this.name=name;
        }
    }

}