我試圖測試下面的類:NullPointerException異常的構造函數定義
public final class ClassA {
private final ClassB member;
public ClassA() {
this.member = new ClassB();
}
}
以下是測試類:
@RunWith(PowerMockRunner.class)
@PrepareForTest({ClassA.class, ClassB.class})
public final class ClassATest {
@Mock
private ClassB mocked;
private ClassA testClass;
@Before
public void initTest() {
PowerMockito.whenNew(ClassB.class).withNoArguments().thenReturn(mocked);
testClass = new ClassA();
}
現在的問題是,我得到一個NullPointerException,它的堆棧跟蹤看起來像:
java.lang.NullPointerException
[junit] at a.a.i.ClassA.<init>(ClassA.java:44)
[junit] at a.a.i.ClassATest.init(ClassATest.java:53)
[junit] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[junit] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
[junit] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
[junit] at java.lang.reflect.Method.invoke(Method.java:606)
[junit] at org.junit.internal.runners.MethodRoadie.runBefores(MethodRoadie.java:132)
[junit] at org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:95)
[junit] at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.executeTest(PowerMockJUnit44RunnerDelegateImpl.java:294)
[junit] at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTestInSuper(PowerMockJUnit47RunnerDelegateImpl.java:127)
[junit] at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTest(PowerMockJUnit47RunnerDelegateImpl.java:82)
[junit] at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:282)
[junit] at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:86)
[junit] at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:49)
[junit] at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:207)
[junit] at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:146)
[junit] at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:120)
[junit] at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:33)
[junit] at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:45)
[junit] at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:122)
[junit] at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:106)
[junit] at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:53)
[junit] at org.powermock.modules.junit4.PowerMockRunner.run(PowerMockRunner.java:59)
[junit] at junit.framework.JUnit4TestAdapter.run(JUnit4TestAdapter.java:38)
[junit] at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.run(JUnitTestRunner.java:532)
[junit] at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.launch(JUnitTestRunner.java:1165)
[junit] at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.main(JUnitTestRunner.java:988)
ClassA的44行是 public Class A(){
ClassATest的第52行是 testClass = new ClassA();
我從來沒有遇到過構造函數定義的NullPointerException,所以我不知道該怎麼做。任何幫助將不勝感激。
什麼是ClassB構造函數? – BlueMoon93
B類的定義是什麼? – Ankur1994a
ClassB具有默認的構造函數(未明確覆蓋) – Ulrich