Ich habe einen Mockito Test-Framework lernen gerade erst begonnen, folgte ich offizielle Tutorial von: developer.android.comMockito auf Android, Context.getString (id) und Nullpointer
Der Code ist:
private static final String FAKE_STRING = "HELLO WORLD";
@Mock
Context mMockContext;
@Test
public void readStringFromContext_LocalizedString() {
// Given a mocked Context injected into the object under test...
when(mMockContext.getString(R.string.hello_world))
.thenReturn(FAKE_STRING);
ClassUnderTest myObjectUnderTest = new ClassUnderTest(mMockContext);
// ...when the string is returned from the object under test...
String result = myObjectUnderTest.getHelloWorldString();
// ...then the result should be the expected one.
assertThat(result, is(FAKE_STRING));
}
Ich schrieb folgende ClassUnderTest:
public class ClassUnderTest {
private Context context;
public ClassUnderTest(Context context)
{
this.context=context;
}
public String getHelloWorldString()
{
return context.getString(R.string.hello_world);
}
}
ein d nach dem Laufen Ich erhalte Nullpointer:
java.lang.NullPointerException
at android.content.Context.getHelloWorldString(Context.java:293)
at com.darekk.draggablelistview.unit_tests.MockitoTest.readStringFromContext_LocalizedString(MockitoTest.java:46)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.mockito.internal.runners.JUnit45AndHigherRunnerImpl.run(JUnit45AndHigherRunnerImpl.java:37)
at org.mockito.runners.MockitoJUnitRunner.run(MockitoJUnitRunner.java:62)
at org.junit.runners.Suite.runChild(Suite.java:128)
at org.junit.runners.Suite.runChild(Suite.java:27)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at org.junit.runner.JUnitCore.run(JUnitCore.java:115)
at android.support.test.internal.runner.TestExecutor.execute(TestExecutor.java:59)
at android.support.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:262)
at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1619)
Wenn ich ersetzen android Kontext mit meiner eigenen Klasse es funktioniert.
Plattform: IntelliJ IDEA Community Edition 15.0.6
Ich schätze jede mögliche Hilfe.
Hmm, sollte ich es innerhalb getHelloWorldString() Methode? wo genau ?, Es ist seltsam. Ich dachte nur Context.getString (...) sollte gestempelt werden. –
Bearbeitete meine Antwort. Keine Notwendigkeit, die zu testende Klasse zu ändern. –
Ich habe dies: when (mMockContext.getString (R.string.hello_world)) .thenReturn (FAKE_STRING); –