我们使用 Powermockito 和 Mockito 来模拟一些静态类。似乎每次都会抛出 java.lang.ExceptionInInitializerError。

你能帮我确定问题出在哪里吗？

被测 Java 类

package com.myproject.myproduct.search.domain;
import org.elasticsearch.index.query.MultiMatchQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;

public class MyQueryBuilder {

    public MultiMatchQueryBuilder getMultiMatchQueryBuilder() {
        MultiMatchQueryBuilder builder = QueryBuilders.multiMatchQuery("term", "field1");
        builder.field("field1",200.9f);
        return builder;
    }
}

使用 Powermock runner 进行 Junit 测试

package com.myproject.myproduct.search.domain;

import org.elasticsearch.index.query.MultiMatchQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.powermock.api.mockito.PowerMockito;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.junit4.PowerMockRunner;

@RunWith(PowerMockRunner.class)
@PrepareForTest(QueryBuilders.class)
public class MyQueryBuilderTest {

    private MyQueryBuilder myQueryBuilder;

    @Test
    public void test() {
        PowerMockito.mockStatic(QueryBuilders.class);
        MultiMatchQueryBuilder builder = PowerMockito.mock(MultiMatchQueryBuilder.class);
    }
}

就是这样。一旦我尝试模拟，测试代码就不起作用 MultiMatchQueryBuilder。

这是异常(exception)情况:

java.lang.ExceptionInInitializerError at org.elasticsearch.common.logging.DeprecationLogger.(DeprecationLogger.java:138) at org.elasticsearch.common.ParseField.(ParseField.java:35) at org.elasticsearch.index.query.AbstractQueryBuilder.(AbstractQueryBuilder.java:53) at sun.reflect.GeneratedSerializationConstructorAccessor7.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Constructor.java:423) at org.objenesis.instantiator.sun.SunReflectionFactoryInstantiator.newInstance(SunReflectionFactoryInstantiator.java:40) at org.objenesis.ObjenesisBase.newInstance(ObjenesisBase.java:59) at org.mockito.internal.creation.jmock.ClassImposterizer.createProxy(ClassImposterizer.java:128) at org.mockito.internal.creation.jmock.ClassImposterizer.imposterise(ClassImposterizer.java:63) at org.powermock.api.mockito.internal.mockcreation.MockCreator.createMethodInvocationControl(MockCreator.java:111) at org.powermock.api.mockito.internal.mockcreation.MockCreator.mock(MockCreator.java:60) at org.powermock.api.mockito.PowerMockito.mock(PowerMockito.java:143) at com.spartasystems.stratas.search.domain.MyQueryBuilderTest.testBoostSetProperly(MyQueryBuilderTest.java:22) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.junit.internal.runners.TestMethod.invoke(TestMethod.java:68) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:310) at org.junit.internal.runners.MethodRoadie$2.run(MethodRoadie.java:88) at org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:96) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.executeTest(PowerMockJUnit44RunnerDelegateImpl.java:294) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTestInSuper(PowerMockJUnit47RunnerDelegateImpl.java:127) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTest(PowerMockJUnit47RunnerDelegateImpl.java:82) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:282) at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:86) at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:49) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:207) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:146) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:120) at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:33) at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:45) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:122) at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:104) at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:53) at org.powermock.modules.junit4.PowerMockRunner.run(PowerMockRunner.java:53) at org.junit.runner.JUnitCore.run(JUnitCore.java:160) at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68) at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47) at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242) at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70) Caused by: java.lang.NullPointerException at org.elasticsearch.Build.(Build.java:47) ... 41 more

Process finished with exit code 255

注意:

可以在这里找到实际底层 elasticsearch 类的源代码

https://github.com/elastic/elasticsearch/blob/master/core/src/main/java/org/elasticsearch/index/query/QueryBuilders.java

和

https://github.com/elastic/elasticsearch/blob/master/core/src/main/java/org/elasticsearch/index/query/MultiMatchQueryBuilder.java

最佳答案

使用模拟调用时 org.elasticsearch.Build#getElasticsearchCodebase

Build.class.getProtectionDomain().getCodeSource().getLocation()

返回null，因为代码没有位置(由cglib生成的动态方法。)

所以当initializing org.elasticsearch.Build在你的模拟代码中使用

final URL url = getElasticsearchCodebase(); // url is null
final String urlStr = url.toString(); // null pointer exception.

当然，模拟不会成功并抛出 ExceptionInInitializerError，这表明在评估静态初始化程序或静态变量的初始化程序期间发生异常。

您可以使用以下代码轻松重现此异常:

@RunWith(PowerMockRunner.class)
@PrepareForTest({QueryBuilders.class})
public class MyQueryBuilderTest {

    @Test
    public void test() {
        final Build current = Build.CURRENT;
    }

}

关于java - PowerMockito(与 Mockito)因 ExceptionInInitializerError 而失败，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/45711275/