{"action":"created","issue":{"url":"https://api.github.com/repos/ReactiveX/RxJava/issues/3857","repository_url":"https://api.github.com/repos/ReactiveX/RxJava","labels_url":"https://api.github.com/repos/ReactiveX/RxJava/issues/3857/labels{/name}","comments_url":"https://api.github.com/repos/ReactiveX/RxJava/issues/3857/comments","events_url":"https://api.github.com/repos/ReactiveX/RxJava/issues/3857/events","html_url":"https://github.com/ReactiveX/RxJava/issues/3857","id":148282532,"number":3857,"title":"about concat operator ","user":{"login":"csshuai","id":1501906,"avatar_url":"https://avatars.githubusercontent.com/u/1501906?v=3","gravatar_id":"","url":"https://api.github.com/users/csshuai","html_url":"https://github.com/csshuai","followers_url":"https://api.github.com/users/csshuai/followers","following_url":"https://api.github.com/users/csshuai/following{/other_user}","gists_url":"https://api.github.com/users/csshuai/gists{/gist_id}","starred_url":"https://api.github.com/users/csshuai/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/csshuai/subscriptions","organizations_url":"https://api.github.com/users/csshuai/orgs","repos_url":"https://api.github.com/users/csshuai/repos","events_url":"https://api.github.com/users/csshuai/events{/privacy}","received_events_url":"https://api.github.com/users/csshuai/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/ReactiveX/RxJava/labels/Question","name":"Question","color":"cc317c"}],"state":"closed","locked":false,"assignee":null,"milestone":null,"comments":2,"created_at":"2016-04-14T07:58:29Z","updated_at":"2016-05-13T12:14:30Z","closed_at":"2016-05-13T12:14:30Z","body":"I use rxjava 1.1.3\r\n\r\n```\r\n    private void test() {\r\n        testConcat().subscribe(new Action1() {\r\n            @Override\r\n            public void call(Object o) {\r\n                Ln.e(\"onNext call\");\r\n            }\r\n        }, new Action1<Throwable>() {\r\n            @Override\r\n            public void call(Throwable throwable) {\r\n                Ln.e(\"onError call\");\r\n            }\r\n        }, new Action0() {\r\n            @Override\r\n            public void call() {\r\n                Ln.e(\"onComplete call\");\r\n            }\r\n        });\r\n    }\r\n\r\n    @RxLogObservable\r\n    private Observable testConcat() {\r\n        return Observable.concat(o1(), o2())\r\n                .subscribeOn(Schedulers.io())\r\n                .observeOn(AndroidSchedulers.mainThread());\r\n    }\r\n\r\n    @RxLogObservable\r\n    private Observable o1() {\r\n        return Observable.create(new Observable.OnSubscribe<Object>() {\r\n            @Override\r\n            public void call(Subscriber<? super Object> subscriber) {\r\n                subscriber.onNext(\"hello\");\r\n                subscriber.onCompleted();\r\n            }\r\n        });\r\n    }\r\n\r\n    @RxLogObservable\r\n    private Observable o2() {\r\n        return Observable.create(new Observable.OnSubscribe<Object>() {\r\n            @Override\r\n            public void call(Subscriber<? super Object> subscriber) {\r\n                throw OnErrorThrowable.from(new RuntimeException(\"sorry\"));\r\n//                subscriber.onNext(\"sorry\");\r\n//                subscriber.onCompleted();\r\n            }\r\n        });\r\n    }\r\n```\r\n\r\nI call test() method log:\r\n\r\n```\r\n04-14 15:50:15.022 12350-12350/com.test D/RxJavaConcat: Frodo => [@Observable :: @InClass -> RxJavaConcat :: @Method -> testConcat()]\r\n04-14 15:50:15.023 12350-12350/com.test D/RxJavaConcat: Frodo => [@Observable :: @InClass -> RxJavaConcat :: @Method -> o1()]\r\n04-14 15:50:15.024 12350-12350/com.test D/RxJavaConcat: Frodo => [@Observable :: @InClass -> RxJavaConcat :: @Method -> o2()]\r\n04-14 15:50:15.024 12350-12350/com.test D/RxJavaConcat: Frodo => [@Observable#testConcat -> onSubscribe()]\r\n04-14 15:50:15.025 12350-25780/com.test D/RxJavaConcat: Frodo => [@Observable#o1 -> onSubscribe()]\r\n04-14 15:50:15.025 12350-25780/com.test D/RxJavaConcat: Frodo => [@Observable#o1 -> onNext() -> hello]\r\n04-14 15:50:15.025 12350-25780/com.test D/RxJavaConcat: Frodo => [@Observable#o1 -> onCompleted()]\r\n04-14 15:50:15.025 12350-25780/com.test D/RxJavaConcat: Frodo => [@Observable#o1 -> onTerminate()]\r\n04-14 15:50:15.025 12350-25780/com.test D/RxJavaConcat: Frodo => [@Observable#o1 -> @Emitted -> 1 element :: @Time -> 0 ms]\r\n04-14 15:50:15.025 12350-25780/com.test D/RxJavaConcat: Frodo => [@Observable#o1 -> @SubscribeOn -> RxCachedThreadScheduler-3 :: @ObserveOn -> RxCachedThreadScheduler-3]\r\n04-14 15:50:15.025 12350-25780/com.test D/RxJavaConcat: Frodo => [@Observable#o1 -> onUnsubscribe()]\r\n04-14 15:50:15.025 12350-25780/com.test D/RxJavaConcat: Frodo => [@Observable#o2 -> onSubscribe()]\r\n04-14 15:50:15.026 12350-25780/com.test D/RxJavaConcat: Frodo => [@Observable#o2 -> onError() -> 'java.lang.RuntimeException: sorry']\r\n04-14 15:50:15.026 12350-25780/com.test D/RxJavaConcat: Frodo => [@Observable#o2 -> onTerminate()]\r\n04-14 15:50:15.026 12350-25780/com.test D/RxJavaConcat: Frodo => [@Observable#o2 -> @Emitted -> 0 elements :: @Time -> 0 ms]\r\n04-14 15:50:15.063 12350-12350/com.test D/RxJavaConcat: Frodo => [@Observable#testConcat -> onError() -> 'java.lang.RuntimeException: sorry']\r\n04-14 15:50:15.063 12350-12350/com.test D/RxJavaConcat: Frodo => [@Observable#testConcat -> onTerminate()]\r\n04-14 15:50:15.063 12350-12350/com.test D/RxJavaConcat: Frodo => [@Observable#testConcat -> @Emitted -> 0 elements :: @Time -> 38 ms]\r\n04-14 15:50:15.063 12350-12350/com.test E/(RxJavaConcat.java:185): main onError call\r\n04-14 15:50:15.063 12350-12350/com.test D/RxJavaConcat: Frodo => [@Observable#testConcat -> @SubscribeOn -> main :: @ObserveOn -> main]\r\n04-14 15:50:15.063 12350-12350/com.test D/RxJavaConcat: Frodo => [@Observable#testConcat -> onUnsubscribe()]\r\n04-14 15:50:15.064 12350-12350/com.test D/RxJavaConcat: Frodo => [@Observable#o2 -> @SubscribeOn -> RxCachedThreadScheduler-3 :: @ObserveOn -> main]\r\n04-14 15:50:15.064 12350-12350/com.test D/RxJavaConcat: Frodo => [@Observable#o2 -> onUnsubscribe()]\r\n```\r\n\r\nSo my question is: why \"onNext call\" is not called"},"comment":{"url":"https://api.github.com/repos/ReactiveX/RxJava/issues/comments/219026791","html_url":"https://github.com/ReactiveX/RxJava/issues/3857#issuecomment-219026791","issue_url":"https://api.github.com/repos/ReactiveX/RxJava/issues/3857","id":219026791,"user":{"login":"akarnokd","id":1269832,"avatar_url":"https://avatars.githubusercontent.com/u/1269832?v=3","gravatar_id":"","url":"https://api.github.com/users/akarnokd","html_url":"https://github.com/akarnokd","followers_url":"https://api.github.com/users/akarnokd/followers","following_url":"https://api.github.com/users/akarnokd/following{/other_user}","gists_url":"https://api.github.com/users/akarnokd/gists{/gist_id}","starred_url":"https://api.github.com/users/akarnokd/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/akarnokd/subscriptions","organizations_url":"https://api.github.com/users/akarnokd/orgs","repos_url":"https://api.github.com/users/akarnokd/repos","events_url":"https://api.github.com/users/akarnokd/events{/privacy}","received_events_url":"https://api.github.com/users/akarnokd/received_events","type":"User","site_admin":false},"created_at":"2016-05-13T12:14:30Z","updated_at":"2016-05-13T12:14:30Z","body":"I'm closing this issue due to inactivity. If you have further input on the issue, don't hesitate to reopen this issue or post a new one."}}