Stream流-04：Stream收集方法collect

package com.zjl.stream;

import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;

/**
 * Created by zjl 2022/5/10
 **/
public class Stream收集方法collect {

  public static void main(String[] args) {

    ArrayList<String> strings = new ArrayList<>();
    strings.add("张无忌");
    strings.add("周芷若");
    strings.add("赵敏");
    strings.add("张强");
    strings.add("张三丰");
    strings.add("张三丰");


    // 1、获取流中姓"张"的并转化为set集合
    Set<String> set = strings.stream().filter(s -> s.startsWith("张")).collect(Collectors.toSet());
    System.out.println(set);
    System.out.println("-----------------------------------");
    // 2、获取流中姓"张"的并转化为list集合
    List<String> list = strings.stream().filter(s -> s.startsWith("张")).collect(Collectors.toList());
    System.out.println(list);
    System.out.println("-----------------------------------");
    // 2、获取流中姓"张"的并转化为数组
    String[] arr = strings.stream().filter(s -> s.startsWith("张")).toArray(String[]::new);
    for (String s : arr) {
      System.out.println(s);
    }
    System.out.println("-----------------------------------");
  }
}
           

运行结果