diff --git a/boot-service/src/main/java/com/xwbing/demo/CollectionDemo.java b/boot-service/src/main/java/com/xwbing/demo/CollectionDemo.java index a8babb7..c46bf2f 100644 --- a/boot-service/src/main/java/com/xwbing/demo/CollectionDemo.java +++ b/boot-service/src/main/java/com/xwbing/demo/CollectionDemo.java @@ -51,17 +51,17 @@ public class CollectionDemo { * 那么就不能表示原来的数组了,会抛出UnsupportedOperationException异常 */ String[] array = {"one", "two", "three", "four"}; - List l = Arrays.asList(array); + List coll = Arrays.asList(array); /* * 所有的集合提供了一个带有collection类型参数的构造方法 该构造方法称为:复制构造器 * 作用是在创建当前集合的同时,集合中包含给定集合中的所有元素 */ - List list1 = new ArrayList(l); + List list1 = new ArrayList<>(coll); /** * 集合转数组 */ - List lsit = new ArrayList(2); + List lsit = new ArrayList<>(2); lsit.add("guan"); lsit.add("bao"); String[] arrayy = new String[lsit.size()];// 大小为list.size() @@ -74,7 +74,7 @@ public class CollectionDemo { /** * 基本api */ - List list = new ArrayList();// 有序 + List list = new ArrayList<>();// 有序 list.add(1); list.add(0, 0);// 元素插入到指定位置 list.add(2); diff --git a/boot-service/src/main/java/com/xwbing/demo/LambdaDemo.java b/boot-service/src/main/java/com/xwbing/demo/LambdaDemo.java index 310e436..31ab198 100644 --- a/boot-service/src/main/java/com/xwbing/demo/LambdaDemo.java +++ b/boot-service/src/main/java/com/xwbing/demo/LambdaDemo.java @@ -82,8 +82,7 @@ public class LambdaDemo { reduce = optional.get(); } //异步回调 -// CompletableFuture> future = CompletableFuture.supplyAsync(LambdaDemo::getList, taskExecutor);//添加时候可以用任务线程池 - CompletableFuture> future = CompletableFuture.supplyAsync(LambdaDemo::getList);//查询不需要任务线程池 + CompletableFuture> future = CompletableFuture.supplyAsync(LambdaDemo::getList); try { List sysUsers = future.get(); } catch (InterruptedException | ExecutionException e) { @@ -103,6 +102,8 @@ public class LambdaDemo { JSONObject object = list.get(i); if (object != null) { futures[i] = CompletableFuture.supplyAsync(() -> finalList.add(setData(object)), taskExecutor); + } else { + futures[i] = CompletableFuture.runAsync(() -> System.out.println("null")); } } // CompletableFuture.allOf(futures).join();//线程等待,效果等同于get(),不用抛检测异常,不推荐 diff --git a/boot-service/src/main/java/com/xwbing/demo/demo.java b/boot-service/src/main/java/com/xwbing/demo/demo.java index 0cd1429..16d0eb8 100644 --- a/boot-service/src/main/java/com/xwbing/demo/demo.java +++ b/boot-service/src/main/java/com/xwbing/demo/demo.java @@ -1,7 +1,8 @@ package com.xwbing.demo; import java.util.ArrayList; -import java.util.LinkedList; +import java.util.List; +import java.util.stream.Collectors; /** * 项目名称: boot-module-demo @@ -11,24 +12,13 @@ import java.util.LinkedList; */ public class demo { public static void main(String[] args) { - - ArrayList objects = new ArrayList<>(); - long l2 = System.currentTimeMillis(); - for (int i=0;i<1000000;i++){ - objects.add(i); - } - long l3 = System.currentTimeMillis(); - System.out.println(l3-l2); - - LinkedList list = new LinkedList<>(); long l = System.currentTimeMillis(); - for (int i=0;i<1000000;i++){ + List list = new ArrayList<>(); + for (int i = 0; i < 100000; i++) { list.add(i); } + list = list.stream().map(integer -> integer * 10).collect(Collectors.toList()); long l1 = System.currentTimeMillis(); - System.out.println(l1-l); - - - + System.out.println(l1 - l); } }