映射器函数返回空值

android java retrofit2 rx-java rx-java2

2022-09-03 01:40:22

我为调试和发布设置了相同的构建类型，

buildTypes {
    debug {
        buildConfigField "String", "API_BASE_URL", "\"https://www.testUrl.com/api/\""
        minifyEnabled true
        shrinkResources true
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        signingConfig signingConfigs.release_key
    }
    release {
        buildConfigField "String", "API_BASE_URL", "\"https://www.testUrl.com/api/\""
        minifyEnabled true
        shrinkResources true
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        signingConfig signingConfigs.release_key
    }
}

但是如果我使用该版本进行构建，则会出现以下错误。此外，服务器响应完全相同。

W/System.err: java.lang.NullPointerException: The mapper function returned a null value.
W/System.err:     at b.a.e.b.b.a(Unknown Source)
W/System.err:     at b.a.e.e.b.bs$a.onNext(Unknown Source)
W/System.err:     at b.a.e.e.b.cm$a.onNext(Unknown Source)
W/System.err:     at retrofit2.adapter.rxjava2.BodyObservable$BodyObserver.onNext(Unknown Source)
W/System.err:     at retrofit2.adapter.rxjava2.BodyObservable$BodyObserver.onNext(Unknown Source)
W/System.err:     at retrofit2.adapter.rxjava2.CallExecuteObservable.subscribeActual(Unknown Source)
W/System.err:     at b.a.l.subscribe(Unknown Source)
W/System.err:     at retrofit2.adapter.rxjava2.BodyObservable.subscribeActual(Unknown Source)
W/System.err:     at b.a.l.subscribe(Unknown Source)
W/System.err:     at b.a.e.e.b.cm$a.a(Unknown Source)
W/System.err:     at b.a.e.e.b.cm.subscribeActual(Unknown Source)
W/System.err:     at b.a.l.subscribe(Unknown Source)
W/System.err:     at b.a.e.e.b.bs.subscribeActual(Unknown Source)
W/System.err:     at b.a.l.subscribe(Unknown Source)
W/System.err:     at b.a.e.e.b.bw.subscribeActual(Unknown Source)
W/System.err:     at b.a.l.subscribe(Unknown Source)
W/System.err:     at b.a.e.e.b.dd$b.run(Unknown Source)
W/System.err:     at b.a.s$a.run(Unknown Source)
W/System.err:     at b.a.e.g.j.run(Unknown Source)
W/System.err:     at b.a.e.g.j.call(Unknown Source)
W/System.err:     at java.util.concurrent.FutureTask.run(FutureTask.java:237)
W/System.err:     at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:272)
W/System.err:     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
W/System.err:     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
W/System.err:     at java.lang.Thread.run(Thread.java:761)

答案 1

问题来自RxJava 2，它不允许将值传递到流中。特别是在您的案例中，您有一个映射器函数，该函数返回一个值，异常清楚地说明了该值。nullnull

您可以使用以下代码块重现它：


    Observable.just(1)
              .map(integer -> null)
              .test()
              .assertError(throwable -> 
                    "The mapper function returned a null value.".equals(throwable.getMessage()));

答案 2