lecture

Author: onjsdnjs

src/main/java/io/concurrency/chapter11/exam10/CompleteExample.java

@@ -3,36 +3,36 @@
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
-import java.util.concurrent.TimeUnit;
 
 public class CompleteExample {
     public static void main(String[] args) {
 
-        MyService myService = new MyService();
+        MyService service = new MyService();
+        CompletableFuture<Integer> cf = service.performTask();
+        cf.thenApply(r -> r + 20);
 
-        CompletableFuture<Integer> future = myService.performTask();
+        System.out.println("result: " + cf.join());
+        System.out.println("메인 스레드 종료");
 
-        future.thenAccept(result -> {
-            System.out.println("비동기 작업 결과: " + result);
-        });
     }
 
-    static class MyService {
+    static class MyService{
 
-        public CompletableFuture<Integer> performTask() {
+        public CompletableFuture<Integer> performTask(){
+
+            CompletableFuture<Integer> cf = new CompletableFuture<>();
 
             ExecutorService executorService = Executors.newSingleThreadExecutor();
-            CompletableFuture<Integer> future = new CompletableFuture<>();
+            executorService.submit(()->{
 
-            executorService.submit(() -> {
                 try {
-                    TimeUnit.SECONDS.sleep(2);
-                    int result = 42;
-                    future.complete(result); // 결과를 완료시킴
-                } catch (InterruptedException e) {}
+                    Thread.sleep(1000);
+                } catch (InterruptedException e) {
+                    throw new RuntimeException(e);
+                }
+                cf.complete(40);
             });
-
-            return future;
+            return cf;
         }
     }
-}
+}

src/main/java/io/concurrency/chapter11/exam10/CompleteOnTimeoutExample.java

@@ -6,14 +6,15 @@
 public class CompleteOnTimeoutExample {
     public static void main(String[] args) {
 
-        getData().completeOnTimeout("Hello Java", 1, TimeUnit.SECONDS)
-        .thenAccept(result -> {
-            System.out.println("결과: " + result);
-        }).join();
+        getData().completeOnTimeout("Hello Java", 2, TimeUnit.SECONDS)
+                .thenAccept(r -> {
+                    System.out.println("r = " + r);
+                }).join();
     }
 
     private static CompletableFuture<String> getData() {
-        return CompletableFuture.supplyAsync(() -> {
+
+        return CompletableFuture.supplyAsync(()->{
             try {
                 Thread.sleep(2000);
                 return "Hello World";

src/main/java/io/concurrency/chapter11/exam10/CompletedFutureExample.java

@@ -5,14 +5,13 @@
 public class CompletedFutureExample {
     public static void main(String[] args) {
 
-        CompletableFuture<String> cf1 = CompletableFuture.completedFuture("Hello World");
+        CompletableFuture<String> cf = CompletableFuture.completedFuture("Hello World");
 
-        CompletableFuture<String> cf2 = new CompletableFuture<>();
-        cf2.complete("Hello World");
+//        CompletableFuture<String> cf2 = new CompletableFuture<>();
+//        cf2.complete("Hello World");
 
-        cf1.thenAccept(user -> {
-            System.out.println("결과: " + user);
+        CompletableFuture<Void> finalCf = cf.thenAccept(r -> {
+            System.out.println("result: " + r);
         });
-
     }
 }

src/main/java/io/concurrency/chapter11/exam10/completeExceptionallyExample.java

@@ -23,14 +23,14 @@ public static void main(String[] args) {
         System.out.println("result: " + cf2.join());
     }
 
-    private static void getData(CompletableFuture<String> cf1) {
+    private static void getData(CompletableFuture cf) {
         try {
-            System.out.println("비동기 작업 수행중");
-            Thread.sleep(100);
-            throw new IllegalArgumentException("error");
+            System.out.println("비동기 작업 수행 중..");
+            Thread.sleep(500);
+//            throw new IllegalArgumentException("error");
         } catch (Exception e) {
-            cf1.completeExceptionally(e);
+            cf.completeExceptionally(e);
         }
-        cf1.complete("Hello World");
+        cf.complete("Hello World");
     }
-}
+}

src/main/java/io/concurrency/chapter11/exam10/isCompletedExceptionallyAndIsCancelledExample.java

@@ -10,8 +10,8 @@ public static void main(String[] args) throws InterruptedException, ExecutionExc
 
         CompletableFuture<Integer> cf1 = CompletableFuture.supplyAsync(() -> 10);
         CompletableFuture<Integer> cf2 = CompletableFuture.supplyAsync(() -> {
-            return 20;
-//            throw new RuntimeException("error");
+//            return 20;
+            throw new RuntimeException("error");
         });
 
 //        cf2.cancel(true);
@@ -35,4 +35,4 @@ else if(cf2.isDone()) {
         int result = combinedFuture.join(); // 결과 가져오기
         System.out.println("최종 결과: " + result);
     }
-}
+}