差異處
這裏顯示兩個版本的差異處。
| Both sides previous revision 前次修改 下次修改 | 前次修改 | ||
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java:java:java8:concurrent:blockingoperationwithcompletablefuture:avoid_transition_task [2019/01/13 14:58] tony [Problem] |
java:java:java8:concurrent:blockingoperationwithcompletablefuture:avoid_transition_task [2023/06/25 09:48] (目前版本) |
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| 行 1: | 行 1: | ||
| + | {{tag>java concurrency}} | ||
| ====== CompletableFuture - Avoid transition task from one thread to another. It costs. ====== | ====== CompletableFuture - Avoid transition task from one thread to another. It costs. ====== | ||
| ===== Problem ===== | ===== Problem ===== | ||
| 行 15: | 行 16: | ||
| @Test | @Test | ||
| public void transitionTask(){ | public void transitionTask(){ | ||
| - | Response reponse = doSmth(); | + | Response response = doSmth(); |
| - | System.out.println(reponse); | + | System.out.println(response); |
| } | } | ||
| </code> | </code> | ||
| 行 24: | 行 25: | ||
| (本篇圖片都來自於[[https://qconsf.com/sf2017/system/files/presentation-slides/cf.pdf|link]]) | (本篇圖片都來自於[[https://qconsf.com/sf2017/system/files/presentation-slides/cf.pdf|link]]) | ||
| ===== How to resolve? ===== | ===== How to resolve? ===== | ||
| + | 針對sync的情況，其實你根本不需要額外透過ExecutorService去執行，client thread就可以幫你完成這個任務。如果是針對async的情況，這時候應該要好好善用CompletableFuture的callback功能才對: | ||
| + | <code java> | ||
| + | @Test | ||
| + | public void fixTransitionTask(){ | ||
| + | doSmthAsync() | ||
| + | .thenAccept(response->{ | ||
| + | System.out.println(response); | ||
| + | }); | ||
| + | } | ||
| + | </code> | ||
| + | 這樣你的client thread就可以回去做它該做的事情，避免在那等待而浪費。 | ||
| ===== Reference ===== | ===== Reference ===== | ||
