java.lang.RuntimeException: PowerMock internal error: Should never throw exception at this level
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.handleException(PowerMockJUnit44RunnerDelegateImpl.java:384)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.evaluateStatement(PowerMockJUnit47RunnerDelegateImpl.java:110)
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:298)
at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:87)
at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:50)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:218)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:160)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:134)
at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:34)
at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:44)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:136)
at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:117)
at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:57)
at org.powermock.modules.junit4.PowerMockRunner.run(PowerMockRunner.java:59)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:69)
at com.intellij.rt.junit.IdeaTestRunner$Repeater$1.execute(IdeaTestRunner.java:38)
at com.intellij.rt.execution.junit.TestsRepeater.repeat(TestsRepeater.java:11)
at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:35)
at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:235)
at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:54)

Caused by: java.lang.reflect.InaccessibleObjectException: Unable to make protected native java.lang.Object java.lang.Object.clone() throws java.lang.CloneNotSupportedException accessible: module java.base does not "opens java.lang" to unnamed module @5be6e01c at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:354) at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:297) at java.base/java.lang.reflect.Method.checkCanSetAccessible(Method.java:199) at java.base/java.lang.reflect.Method.setAccessible(Method.java:193) at org.powermock.reflect.internal.WhiteboxImpl.doGetAllMethods(WhiteboxImpl.java:1508) at org.powermock.reflect.internal.WhiteboxImpl.getAllMethods(WhiteboxImpl.java:1482) at org.powermock.reflect.internal.WhiteboxImpl.findMethodOrThrowException(WhiteboxImpl.java:862) at org.powermock.reflect.internal.WhiteboxImpl.doInvokeMethod(WhiteboxImpl.java:822) at org.powermock.reflect.internal.WhiteboxImpl.invokeMethod(WhiteboxImpl.java:690) at org.powermock.reflect.Whitebox.invokeMethod(Whitebox.java:401) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.handleException(PowerMockJUnit44RunnerDelegateImpl.java:361) ... 21 more
Process finished with exit code -2
java.lang.reflect.InaccessibleObjectException: Unable to make protected native java.lang.Object java.lang.Object.clone() throws java.lang.CloneNotSupportedException accessible: module java.base does not "opens java.lang" to unnamed module @6d21714c

at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:354)
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:297)
at java.base/java.lang.reflect.Method.checkCanSetAccessible(Method.java:199)
at java.base/java.lang.reflect.Method.setAccessible(Method.java:193)
at org.powermock.reflect.internal.WhiteboxImpl.doGetAllMethods(WhiteboxImpl.java:1508)
at org.powermock.reflect.internal.WhiteboxImpl.getAllMethods(WhiteboxImpl.java:1482)
at org.powermock.reflect.internal.WhiteboxImpl.findMethodOrThrowException(WhiteboxImpl.java:862)
at org.powermock.reflect.internal.WhiteboxImpl.doInvokeMethod(WhiteboxImpl.java:822)
at org.powermock.reflect.internal.WhiteboxImpl.invokeMethod(WhiteboxImpl.java:805)
at org.powermock.reflect.Whitebox.invokeMethod(Whitebox.java:466)
at org.powermock.modules.junit4.common.internal.impl.PowerMockJUnit4RunListener.testFinished(PowerMockJUnit4RunListener.java:55)
at org.junit.runner.notification.SynchronizedRunListener.testFinished(SynchronizedRunListener.java:87)
at org.junit.runner.notification.RunNotifier$9.notifyListener(RunNotifier.java:225)
at org.junit.runner.notification.RunNotifier$SafeNotifier.run(RunNotifier.java:72)
at org.junit.runner.notification.RunNotifier.fireTestFinished(RunNotifier.java:222)
at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:53)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:218)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:160)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:134)
at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:34)
at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:44)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:136)
at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:117)
at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:57)
at org.powermock.modules.junit4.PowerMockRunner.run(PowerMockRunner.java:59)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:69)
at com.intellij.rt.junit.IdeaTestRunner$Repeater$1.execute(IdeaTestRunner.java:38)
at com.intellij.rt.execution.junit.TestsRepeater.repeat(TestsRepeater.java:11)
at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:35)
at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:235)
at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:54)

import static org.junit.Assert.assertEquals;
import static org.mockito.Mockito.*;

import java.util.ArrayList;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.powermock.api.mockito.PowerMockito;
import org.powermock.core.classloader.annotations.PowerMockIgnore;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.junit4.PowerMockRunner;

@RunWith(PowerMockRunner.class)
@PrepareForTest({ SystemUnderTest.class /*To be able to mock the Constructor, we need to add in the Class that creates the new object*/})
@PowerMockIgnore({"javax.management.*", "javax.xml.*", "org.xml.sax.*", "org.w3c.dom.*", "org.springframework.context.*", "org.apache.log4j.*", "org.apache.commons.logging.*", "org.jacoco.*", "jdk.internal.reflect.*"})
public class PowerMockitoMockingConstructorTest {

    private static final int SOME_DUMMY_SIZE = 100;

    @Mock
    Dependency dependencyMock;

    @InjectMocks
    SystemUnderTest systemUnderTest;

    @Test
    public void powerMockito_MockingAConstructor() throws Exception {

        ArrayList<String> mockList = mock(ArrayList.class);

        stub(mockList.size()).toReturn(SOME_DUMMY_SIZE);

        PowerMockito.whenNew(ArrayList.class).withAnyArguments().thenReturn(
                mockList);

        int size = systemUnderTest.methodUsingAnArrayListConstructor();

        assertEquals(SOME_DUMMY_SIZE, size);
    }
}