Vert.x：Result is already complete

问题由来：

在Vertx项目中，有时抛出一个异常
严重: Unhandled exception
ava.lang.IllegalStateException: Result is already complete: succeeded
at io.vertx.core.impl.FutureImpl.complete(FutureImpl.java:107)
at io.vertx.core.impl.FutureImpl.handle(FutureImpl.java:164)
at io.vertx.core.impl.FutureImpl.handle(FutureImpl.java:23)
at io.vertx.core.impl.FutureImpl.checkCallHandler(FutureImpl.java:188)
at io.vertx.core.impl.FutureImpl.tryComplete(FutureImpl.java:139)

......

顾名思义，是在future执行complete之前已经被complete掉了。

   于是，码代码验证一下：

@Testpublic void voidTest(TestContext context) {    Async async = context.async();    Future fut1 = Future.future();    fut1.setHandler(Future.succeededFuture());    vertx.executeBlocking(fut -> {        System.out.println("doing some bloking operation");        fut.complete();    }, result -> {        System.out.println("success");        fut1.complete();    });}

异常抛出如下：

doing some bloking operationsuccess六月 15, 2017 9:53:24 上午 io.vertx.core.impl.ContextImpl严重: Unhandled exceptionjava.lang.IllegalStateException: Result is already complete: succeeded

......

结论：

慎用Future.successedFuture();