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Access java.lang.management.* via reflection (junit-team#1187)
Several platforms, including Android and j2objc, do not provide the java management APIs and crash or otherwise fail when encountering code that imports or uses these APIs directly.
1 parent 0dfdcd0 commit 2cd912f

9 files changed

+319
-4
lines changed

‎src/main/java/org/junit/internal/management/FakeRuntimeMXBean.java

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package org.junit.internal.management;
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import java.util.Collections;
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import java.util.List;
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/**
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* No-op implementation of RuntimeMXBean when the platform doesn't provide it.
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*/
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class FakeRuntimeMXBean implements RuntimeMXBean {
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/**
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* {@inheritDoc}
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*
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* <p>Always returns an empty list.
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*/
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@Override
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public List<String> getInputArguments() {
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return Collections.emptyList();
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}
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}
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‎src/main/java/org/junit/internal/management/FakeThreadMXBean.java

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package org.junit.internal.management;
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/**
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* No-op implementation of ThreadMXBean when the platform doesn't provide it.
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*/
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final class FakeThreadMXBean implements ThreadMXBean {
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/**
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* {@inheritDoc}
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*
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* <p>Always throws an {@link UnsupportedOperationException}
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*/
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@Override
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public long getThreadCpuTime(long id) {
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throw new UnsupportedOperationException();
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}
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/**
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* {@inheritDoc}
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*
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* <p>Always returns false.
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*/
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@Override
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public boolean isThreadCpuTimeSupported() {
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return false;
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}
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}
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‎src/main/java/org/junit/internal/management/ManagementFactory.java

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package org.junit.internal.management;
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import org.junit.internal.Classes;
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import java.lang.reflect.InvocationTargetException;
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/**
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* Reflective wrapper around {@link java.lang.management.ManagementFactory}
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*/
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public class ManagementFactory {
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private static final class FactoryHolder {
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private static final Class<?> MANAGEMENT_FACTORY_CLASS;
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static {
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Class<?> managementFactoryClass = null;
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try {
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managementFactoryClass = Classes.getClass("java.lang.management.ManagementFactory");
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} catch (ClassNotFoundException e) {
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// do nothing, managementFactoryClass will be none on failure
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}
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MANAGEMENT_FACTORY_CLASS = managementFactoryClass;
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}
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static Object getBeanObject(String methodName) {
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if (MANAGEMENT_FACTORY_CLASS != null) {
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try {
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return MANAGEMENT_FACTORY_CLASS.getMethod(methodName).invoke(null);
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} catch (IllegalAccessException e) {
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// fallthrough
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} catch (IllegalArgumentException e) {
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// fallthrough
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} catch (InvocationTargetException e) {
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// fallthrough
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} catch (NoSuchMethodException e) {
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// fallthrough
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} catch (SecurityException e) {
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// fallthrough
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}
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}
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return null;
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}
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}
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private static final class RuntimeHolder {
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private static final RuntimeMXBean RUNTIME_MX_BEAN =
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getBean(FactoryHolder.getBeanObject("getRuntimeMXBean"));
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private static final RuntimeMXBean getBean(Object runtimeMxBean) {
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return runtimeMxBean != null
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? new ReflectiveRuntimeMXBean(runtimeMxBean) : new FakeRuntimeMXBean();
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}
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}
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private static final class ThreadHolder {
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private static final ThreadMXBean THREAD_MX_BEAN =
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getBean(FactoryHolder.getBeanObject("getThreadMXBean"));
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private static final ThreadMXBean getBean(Object threadMxBean) {
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return threadMxBean != null
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? new ReflectiveThreadMXBean(threadMxBean) : new FakeThreadMXBean();
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}
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}
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/**
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* @see java.lang.management.ManagementFactory#getRuntimeMXBean()
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*/
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public static RuntimeMXBean getRuntimeMXBean() {
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return RuntimeHolder.RUNTIME_MX_BEAN;
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}
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/**
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* @see java.lang.management.ManagementFactory#getThreadMXBean()
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*/
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public static ThreadMXBean getThreadMXBean() {
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return ThreadHolder.THREAD_MX_BEAN;
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}
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}

‎src/main/java/org/junit/internal/management/ReflectiveRuntimeMXBean.java

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package org.junit.internal.management;
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import org.junit.internal.Classes;
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import java.lang.reflect.InvocationTargetException;
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import java.lang.reflect.Method;
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import java.util.Collections;
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import java.util.List;
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/**
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* Implementation of {@link RuntimeMXBean} using the JVM reflectively.
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*/
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final class ReflectiveRuntimeMXBean implements RuntimeMXBean {
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private final Object runtimeMxBean;
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private static final class Holder {
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private static final Method getInputArgumentsMethod;
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static {
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Method inputArguments = null;
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try {
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Class<?> threadMXBeanClass = Classes.getClass("java.lang.management.RuntimeMXBean");
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inputArguments = threadMXBeanClass.getMethod("getInputArguments");
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} catch (ClassNotFoundException e) {
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// do nothing, input arguments will be null on failure
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} catch (NoSuchMethodException e) {
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// do nothing, input arguments will be null on failure
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} catch (SecurityException e) {
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// do nothing, input arguments will be null on failure
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}
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getInputArgumentsMethod = inputArguments;
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}
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}
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ReflectiveRuntimeMXBean(Object runtimeMxBean) {
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super();
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this.runtimeMxBean = runtimeMxBean;
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}
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/**
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* {@inheritDoc}
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*/
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@SuppressWarnings("unchecked")
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@Override
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public List<String> getInputArguments() {
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if (Holder.getInputArgumentsMethod != null) {
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try {
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return (List<String>) Holder.getInputArgumentsMethod.invoke(runtimeMxBean);
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} catch (ClassCastException e) { // no multi-catch with source level 6
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// fallthrough
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} catch (IllegalAccessException e) {
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// fallthrough
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} catch (IllegalArgumentException e) {
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// fallthrough
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} catch (InvocationTargetException e) {
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// fallthrough
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}
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}
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return Collections.emptyList();
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}
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}
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‎src/main/java/org/junit/internal/management/ReflectiveThreadMXBean.java

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package org.junit.internal.management;
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import org.junit.internal.Classes;
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import java.lang.reflect.InvocationTargetException;
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import java.lang.reflect.Method;
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/**
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* Implementation of {@link ThreadMXBean} using the JVM reflectively.
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*/
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final class ReflectiveThreadMXBean implements ThreadMXBean {
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private final Object threadMxBean;
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private static final class Holder {
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static final Method getThreadCpuTimeMethod;
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static final Method isThreadCpuTimeSupportedMethod;
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private static final String FAILURE_MESSAGE = "Unable to access ThreadMXBean";
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static {
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Method threadCpuTime = null;
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Method threadCpuTimeSupported = null;
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try {
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Class<?> threadMXBeanClass = Classes.getClass("java.lang.management.ThreadMXBean");
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threadCpuTime = threadMXBeanClass.getMethod("getThreadCpuTime", long.class);
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threadCpuTimeSupported = threadMXBeanClass.getMethod("isThreadCpuTimeSupported");
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} catch (ClassNotFoundException e) {
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// do nothing, the methods will be null on failure
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} catch (NoSuchMethodException e) {
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// do nothing, the methods will be null on failure
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} catch (SecurityException e) {
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// do nothing, the methods will be null on failure
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}
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getThreadCpuTimeMethod = threadCpuTime;
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isThreadCpuTimeSupportedMethod = threadCpuTimeSupported;
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}
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}
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ReflectiveThreadMXBean(Object threadMxBean) {
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super();
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this.threadMxBean = threadMxBean;
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}
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/**
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* {@inheritDoc}
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*/
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@Override
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public long getThreadCpuTime(long id) {
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if (Holder.getThreadCpuTimeMethod != null) {
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Exception error = null;
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try {
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return (Long) Holder.getThreadCpuTimeMethod.invoke(threadMxBean, id);
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} catch (ClassCastException e) {
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error = e;
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// fallthrough
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} catch (IllegalAccessException e) {
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error = e;
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// fallthrough
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} catch (IllegalArgumentException e) {
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error = e;
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// fallthrough
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} catch (InvocationTargetException e) {
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error = e;
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// fallthrough
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}
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throw new UnsupportedOperationException(Holder.FAILURE_MESSAGE, error);
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}
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throw new UnsupportedOperationException(Holder.FAILURE_MESSAGE);
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}
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/**
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* {@inheritDoc}
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*/
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@Override
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public boolean isThreadCpuTimeSupported() {
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if (Holder.isThreadCpuTimeSupportedMethod != null) {
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try {
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return (Boolean) Holder.isThreadCpuTimeSupportedMethod.invoke(threadMxBean);
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} catch (ClassCastException e) {
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// fallthrough
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} catch (IllegalAccessException e) {
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// fallthrough
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} catch (IllegalArgumentException e) {
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// fallthrough
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} catch (InvocationTargetException e) {
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// fallthrough
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}
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}
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return false;
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}
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}
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‎src/main/java/org/junit/internal/management/RuntimeMXBean.java

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package org.junit.internal.management;
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import java.util.List;
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/**
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* Wrapper for {@link java.lang.management.RuntimeMXBean}.
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*/
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public interface RuntimeMXBean {
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/**
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* @see java.lang.management.RuntimeMXBean#getInputArguments()
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*/
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List<String> getInputArguments();
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}

‎src/main/java/org/junit/internal/management/ThreadMXBean.java

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package org.junit.internal.management;
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/**
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* Wrapper for {@link java.lang.management.ThreadMXBean}.
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*/
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public interface ThreadMXBean {
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/**
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* @see java.lang.management.ThreadMXBean#getThreadCpuTime(long)
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*/
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long getThreadCpuTime(long id);
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/**
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* @see java.lang.management.ThreadMXBean#isThreadCpuTimeSupported()
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*/
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boolean isThreadCpuTimeSupported();
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}
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‎src/main/java/org/junit/internal/runners/statements/FailOnTimeout.java

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package org.junit.internal.runners.statements;
22

3-
import java.lang.management.ManagementFactory;
4-
import java.lang.management.ThreadMXBean;
53
import java.util.Arrays;
64
import java.util.Collections;
75
import java.util.List;
@@ -12,6 +10,8 @@
1210
import java.util.concurrent.TimeUnit;
1311
import java.util.concurrent.TimeoutException;
1412

13+
import org.junit.internal.management.ManagementFactory;
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import org.junit.internal.management.ThreadMXBean;
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import org.junit.runners.model.MultipleFailureException;
1616
import org.junit.runners.model.Statement;
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import org.junit.runners.model.TestTimedOutException;

‎src/main/java/org/junit/rules/DisableOnDebug.java

+2-2
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11
package org.junit.rules;
22

3-
import java.lang.management.ManagementFactory;
4-
import java.lang.management.RuntimeMXBean;
53
import java.util.List;
64

5+
import org.junit.internal.management.ManagementFactory;
6+
import org.junit.internal.management.RuntimeMXBean;
77
import org.junit.runner.Description;
88
import org.junit.runners.model.Statement;
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