lecture

Author: onjsdnjs

src/main/java/io/concurrency/chapter11/exam09/ExceptionallyExample.java

@@ -1,33 +1,24 @@
 package io.concurrency.chapter11.exam09;
 
-
 import java.util.concurrent.CompletableFuture;
 
 public class ExceptionallyExample {
     public static void main(String[] args) {
 
-
-        CompletableFuture<Object> cf = CompletableFuture.supplyAsync(() -> {
+        CompletableFuture<Integer> cf = CompletableFuture.supplyAsync(() -> {
                     try {
                         Thread.sleep(500);
-                        throw new RuntimeException("error");
-
+                        throw new IllegalArgumentException("error");
                     } catch (InterruptedException e) {
                         Thread.currentThread().interrupt();
                     }
                     return 10;
-                })
-                .thenApply(r -> r + 20)
-                .exceptionally(ex -> {
-                    System.err.println("최종 예외 처리: " + ex.getMessage());
-                    return -1;
-                }).thenApply(r -> {
-                    throw new IllegalArgumentException("error");
-                }).exceptionally(ex -> {
-                    System.err.println("최종 예외 처리: " + ex.getMessage());
+                }).thenApply(r -> r + 20)
+                .exceptionally(e -> {
+                    System.out.println("Exception: " + e.getMessage());
                     return -1;
                 });
 
-        System.out.println("result: " + cf.join());
+        System.out.println("result: " +cf.join());
     }
 }

src/main/java/io/concurrency/chapter11/exam09/HandleExample.java

@@ -12,33 +12,32 @@ public static void main(String[] args) {
                         Thread.currentThread().interrupt();
                     }
                     return 10;
-                })
-                .handle((r, e) -> {
-                    if (e != null) {
-                        System.err.println("비동기 예외 처리 1: " + e.getMessage());
-                        return -1; // 예외 발생 시 기본값 반환
+                }).handle((r, e) ->{
+                    if(e !=null){
+                        System.out.println("비동기 예외처리 1: " + e.getMessage());
+                        return -1;
                     }
                     return r;
                 });
 
         CompletableFuture<Integer> cf2 = CompletableFuture.supplyAsync(() -> {
                     try {
                         Thread.sleep(500);
-//                        throw new RuntimeException("error");
+                        throw new RuntimeException("error");
 
                     } catch (InterruptedException e) {
                         Thread.currentThread().interrupt();
                     }
                     return 20;
-                })
-                .handle((r, e) -> {
-                    if (e != null) {
-                        System.err.println("비동기 예외 처리 2: " + e.getMessage());
-                        return -1; // 예외 발생 시 기본값 반환
+                }).handle((r, e) ->{
+                    if(e !=null){
+                        System.out.println("비동기 예외처리 2: " + e.getMessage());
+                        return -1;
                     }
                     return r;
                 });
 
+
         CompletableFuture<Integer> cf3 = cf1.thenCombine(cf2, (r1, r2) -> {
             if (r1 == -1 || r2 == -1) {
                 // 둘 중 하나라도 예외가 발생하면 예외 처리

src/main/java/io/concurrency/chapter11/exam09/WhenCompleteExample.java

@@ -1,37 +1,34 @@
 package io.concurrency.chapter11.exam09;
 
 import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.ExecutionException;
+import java.util.concurrent.CompletionException;
 
 public class WhenCompleteExample {
-    public static void main(String[] args) {
+    public static void main(String[] args) throws InterruptedException {
 
-        CompletableFuture<Integer> cf = CompletableFuture.supplyAsync(() -> {
-                    try {
-                        Thread.sleep(500);
-                        throw new RuntimeException("error");
-                    } catch (InterruptedException e) {
-                        Thread.currentThread().interrupt();
-                    }
-                    return 10;
-                })
-                .whenComplete((r, e) -> {
-                    if (e != null) {
-                        System.err.println("예외 발생: " + e.getMessage());
-                        // 예외 처리
-                    } else {
-                        // 결과 처리
-                        System.out.println("결과: " + r);
-                    }
-                });
+    CompletableFuture<Integer> cf = CompletableFuture.supplyAsync(() -> {
+                try {
+                    Thread.sleep(500);
+                    throw new RuntimeException("error");
+                } catch (InterruptedException e) {
+                    Thread.currentThread().interrupt();
+                }
+                return 10;
+            }).whenComplete((r,e) ->{
+                if(e != null){
+                    System.out.println("Exception: " + e.getMessage());
+                }else{
+                    System.out.println("result: " + r);
+                }
+             });
 
         try {
-            cf.get();
-        } catch (InterruptedException ex) {
-            System.out.println("예외 처리: " + ex.getMessage());
-
-        } catch (ExecutionException ex) {
-            System.out.println("예외 처리: " + ex.getMessage());
+            Thread.sleep(2000);
+            cf.join();
+        }catch(CompletionException e){
+            System.out.println("예외 처리를 합니다");
+        } catch (InterruptedException e) {
+            throw new RuntimeException(e);
         }
     }
 }