mockit.internal.startup.AgentLoader Maven / Gradle / Ivy
/*
* Copyright (c) 2006 Rogério Liesenfeld
* This file is subject to the terms of the MIT license (see LICENSE.txt).
*/
package mockit.internal.startup;
import java.io.*;
import java.lang.management.*;
import java.lang.reflect.*;
import java.util.*;
import javax.annotation.*;
import static mockit.internal.util.Utilities.*;
import com.sun.tools.attach.*;
import com.sun.tools.attach.spi.*;
import sun.tools.attach.*;
public final class AgentLoader
{
private static final AttachProvider ATTACH_PROVIDER = new AttachProvider() {
@Override @Nullable public String name() { return null; }
@Override @Nullable public String type() { return null; }
@Override @Nullable public VirtualMachine attachVirtualMachine(String id) { return null; }
@Override @Nullable public List listVirtualMachines() { return null; }
};
@Nonnull private final String jarFilePath;
@Nullable private String pidForTargetVM;
AgentLoader()
{
if (JAVA_VERSION < 1.6F) {
throw new IllegalStateException("JMockit requires a Java 6+ VM");
}
jarFilePath = PathToAgentJar.getPathToJarFile();
}
public AgentLoader(@Nonnull String pid)
{
this();
pidForTargetVM = pid;
}
public void loadAgent(@Nullable String options)
{
VirtualMachine vm;
if (AttachProvider.providers().isEmpty()) {
if (HOTSPOT_VM) {
vm = getVirtualMachineImplementationFromEmbeddedOnes();
}
else {
String helpMessage = getHelpMessageForNonHotSpotVM();
throw new IllegalStateException(helpMessage);
}
}
else {
vm = attachToRunningVM();
}
loadAgentAndDetachFromRunningVM(vm, options);
}
@Nonnull
private VirtualMachine getVirtualMachineImplementationFromEmbeddedOnes()
{
Class vmClass = findVirtualMachineClassAccordingToOS();
Class[] parameterTypes = {AttachProvider.class, String.class};
String pid = getProcessIdForTargetVM();
try {
// This is only done with Reflection to avoid the JVM pre-loading all the XyzVirtualMachine classes.
Constructor vmConstructor = vmClass.getConstructor(parameterTypes);
VirtualMachine newVM = vmConstructor.newInstance(ATTACH_PROVIDER, pid);
return newVM;
}
catch (NoSuchMethodException e) { throw new RuntimeException(e); }
catch (InvocationTargetException e) { throw new RuntimeException(e); }
catch (InstantiationException e) { throw new RuntimeException(e); }
catch (IllegalAccessException e) { throw new RuntimeException(e); }
catch (NoClassDefFoundError e) {
throw new IllegalStateException("Native library for Attach API not available in this JRE", e);
}
catch (UnsatisfiedLinkError e) {
throw new IllegalStateException("Native library for Attach API not available in this JRE", e);
}
}
@Nonnull
private static Class findVirtualMachineClassAccordingToOS()
{
if (File.separatorChar == '\\') {
return WindowsVirtualMachine.class;
}
String osName = System.getProperty("os.name");
if (osName.startsWith("Linux") || osName.startsWith("LINUX")) {
return LinuxVirtualMachine.class;
}
if (osName.contains("FreeBSD") || osName.startsWith("Mac OS X")) {
return BsdVirtualMachine.class;
}
if (osName.startsWith("Solaris") || osName.contains("SunOS")) {
return SolarisVirtualMachine.class;
}
throw new IllegalStateException("Cannot use Attach API on unknown OS: " + osName);
}
@Nonnull
private String getProcessIdForTargetVM()
{
if (pidForTargetVM != null) {
return pidForTargetVM;
}
String nameOfRunningVM = ManagementFactory.getRuntimeMXBean().getName();
int p = nameOfRunningVM.indexOf('@');
return nameOfRunningVM.substring(0, p);
}
@Nonnull
private String getHelpMessageForNonHotSpotVM()
{
String vmName = System.getProperty("java.vm.name");
String helpMessage = "To run on " + vmName;
if (vmName.contains("J9")) {
helpMessage += ", add /lib/tools.jar to the runtime classpath (before jmockit), or";
}
return helpMessage + " use -javaagent:" + jarFilePath;
}
@Nonnull
private VirtualMachine attachToRunningVM()
{
String pid = getProcessIdForTargetVM();
try {
return VirtualMachine.attach(pid);
}
catch (AttachNotSupportedException e) { throw new RuntimeException(e); }
catch (IOException e) {
if (e.getMessage().contains("current VM")) {
throw new IllegalStateException(
"Running on JDK 9 requires -javaagent:/jmockit-1.n.jar or -Djdk.attach.allowAttachSelf");
}
throw new RuntimeException(e);
}
}
private void loadAgentAndDetachFromRunningVM(@Nonnull VirtualMachine vm, @Nullable String options)
{
try {
vm.loadAgent(jarFilePath, options);
vm.detach();
}
catch (AgentLoadException e) { throw new IllegalStateException(e); }
catch (AgentInitializationException e) { throw new IllegalStateException(e); }
catch (IOException e) { throw new RuntimeException(e); }
}
}