merge

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<String> l = Arrays.asList(array);
+        List<String> 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<String> list1 = new ArrayList<String>(l);
+        List<String> list1 = new ArrayList<>(coll);
 
         /**
          * 集合转数组
          */
-        List<String> lsit = new ArrayList<String>(2);
+        List<String> 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<Integer> list = new ArrayList<Integer>();// 有序
+        List<Integer> list = new ArrayList<>();// 有序
         list.add(1);
         list.add(0, 0);// 元素插入到指定位置
         list.add(2);

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<List<SysUser>> future = CompletableFuture.supplyAsync(LambdaDemo::getList, taskExecutor);//添加时候可以用任务线程池
-        CompletableFuture<List<JSONObject>> future = CompletableFuture.supplyAsync(LambdaDemo::getList);//查询不需要任务线程池
+        CompletableFuture<List<JSONObject>> future = CompletableFuture.supplyAsync(LambdaDemo::getList);
         try {
             List<JSONObject> 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

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<Integer> 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<Integer> list = new LinkedList<>();
         long l = System.currentTimeMillis();
-        for (int i=0;i<1000000;i++){
+        List<Integer> 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);
     }
 }