java 映射器函数返回空值
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The mapper function returned a null value
提问by Expert wanna be
I set same build types for debug and release,
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
}
}
But If I build with the release, I got the below error. Also, the server response is exactly same.
但是，如果我使用发行版进行构建，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)
回答by azizbekian
The problem comes from RxJava 2, which won't allow nullvalues to be passed down the stream. In particularly your case, you have a mapper function, that returns a nullvalue, which the exception clearly states.
问题来自 RxJava 2，它不允许null值在流中传递。特别是在您的情况下，您有一个映射器函数，它返回一个null值，异常清楚地说明了该值。
You can reproduce that with following chunk of code:
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()));
