Merge pull request #464 from grgrzybek/jdk11-vm-attach-api

[#394] Provide non-reflective access to JVM Attach API on JDK9+

agent/jmx/src/main/java/org/jolokia/jmx/JolokiaMBeanServer.java

@@ -108,6 +108,21 @@ private JsonMBean extractJsonMBeanAnnotation(Object object) {
                 }
             } catch (IllegalAccessException e) {
                 // Ignored silently, but we tried it at least
+            } catch (RuntimeException e) {
+                // See https://openjdk.java.net/jeps/403
+                // On JDK9-JDK15 (with --illegal-access=deny) or on JDK-16+ (by default),
+                // java.lang.reflect.InaccessibleObjectException is thrown.
+                // --illegal-access=permit|warn|debug always ends with at least one WARNING message. The only
+                // way to handle the reflection gently is by using:
+                //     --illegal-access=deny \
+                //     --add-opens java.management/javax.management.modelmbean=ALL-UNNAMED
+                // without deny, we can't detect up front (using JDK8 API) if we can safely call setAccessible()...
+                if (e.getClass().getName().equals("java.lang.reflect.InaccessibleObjectException")) {
+                    // ignore
+                    isAccessible = null;
+                } else {
+                    throw e;
+                }
             } finally {
                 if (isAccessible != null) {
                     field.setAccessible(isAccessible);

agent/jvm/pom.xml

@@ -105,7 +105,6 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-shade-plugin</artifactId>
-        <version>2.3</version>
         <executions>
           <execution>
             <phase>package</phase>
@@ -153,7 +152,8 @@
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-surefire-plugin</artifactId>
         <configuration>
-          <forkMode>always</forkMode>
+          <forkCount>1</forkCount>
+          <reuseForks>false</reuseForks>
           <!--<argLine>-Djava.security.debug=certpath,Provider</argLine>-->
         </configuration>
       </plugin>

agent/jvm/src/main/java/org/jolokia/jvmagent/client/AgentLauncher.java

@@ -50,7 +50,7 @@ public static void main(String... args) {
         OptionsAndArgs options;
         try {
             options = new OptionsAndArgs(CommandDispatcher.getAvailableCommands(),args);
-            VirtualMachineHandler vmHandler = new VirtualMachineHandler(options);
+            VirtualMachineHandlerOperations vmHandler = PlatformUtils.createVMAccess(options);
             CommandDispatcher dispatcher = new CommandDispatcher(options);
 
             // Attach a VirtualMachine to a given PID (if PID is given)

agent/jvm/src/main/java/org/jolokia/jvmagent/client/command/AbstractBaseCommand.java

@@ -17,12 +17,11 @@
  */
 
 import java.lang.reflect.InvocationTargetException;
-import java.lang.reflect.Method;
 import java.util.Properties;
 
 import org.jolokia.jvmagent.JvmAgent;
 import org.jolokia.jvmagent.client.util.OptionsAndArgs;
-import org.jolokia.jvmagent.client.util.VirtualMachineHandler;
+import org.jolokia.jvmagent.client.util.VirtualMachineHandlerOperations;
 
 /**
  * Stateless Base command providing helper functions
@@ -51,25 +50,24 @@ public abstract class AbstractBaseCommand {
      * @throws InvocationTargetException exception occured during startup of the agent. You probably need to examine
      *         the stdout of the instrumented process as well for error messages.
       */
-    abstract int execute(OptionsAndArgs pOpts, Object pVm,VirtualMachineHandler pHandler) throws InvocationTargetException, NoSuchMethodException, IllegalAccessException;
+    abstract int execute(OptionsAndArgs pOpts, Object pVm, VirtualMachineHandlerOperations pHandler) throws InvocationTargetException, NoSuchMethodException, IllegalAccessException;
 
     // =======================================================================================================
 
     /**
-     * Execute {@link com.sun.tools.attach.VirtualMachine#loadAgent(String, String)} via reflection
+     * Execute {@code com.sun.tools.attach.VirtualMachine#loadAgent(String, String)}
      *
      * @param pVm the VirtualMachine object, typeless
+     * @param pHandler platform-specific way to invoke operations on VM
      * @param pOpts options from where to extract the agent path and options
      * @param pAdditionalOpts optional additional options to be appended to the agent options. Must be a CSV string.
      */
-    protected void loadAgent(Object pVm, OptionsAndArgs pOpts,String ... pAdditionalOpts) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
-        Class clazz = pVm.getClass();
-        Method method = clazz.getMethod("loadAgent",String.class, String.class);
+    protected void loadAgent(Object pVm, VirtualMachineHandlerOperations pHandler, OptionsAndArgs pOpts, String ... pAdditionalOpts) {
         String args = pOpts.toAgentArg();
         if (pAdditionalOpts.length > 0) {
             args = args.length() != 0 ? args + "," + pAdditionalOpts[0] : pAdditionalOpts[0];
         }
-        method.invoke(pVm, pOpts.getJarFilePath(),args.length() > 0 ? args : null);
+        pHandler.loadAgent(pVm, pOpts.getJarFilePath(), args.length() > 0 ? args : null);
     }
 
     /**
@@ -78,10 +76,11 @@ protected void loadAgent(Object pVm, OptionsAndArgs pOpts,String ... pAdditional
      * has been already attached and started. ("start" will set this property, "stop" will remove it).
      *
      * @param pVm the {@link com.sun.tools.attach.VirtualMachine}, but typeless
+     * @param pHandler platform-specific way to invoke operations on VM
      * @return the agent URL if it is was set by a previous 'start' command.
      */
-    protected String checkAgentUrl(Object pVm) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
-        return checkAgentUrl(pVm, 0);
+    protected String checkAgentUrl(Object pVm, VirtualMachineHandlerOperations pHandler) {
+        return checkAgentUrl(pVm, pHandler, 0);
     }
 
     /**
@@ -90,58 +89,50 @@ protected String checkAgentUrl(Object pVm) throws NoSuchMethodException, Invocat
      * has been already attached and started. ("start" will set this property, "stop" will remove it).
      *
      * @param pVm the {@link com.sun.tools.attach.VirtualMachine}, but typeless
+     * @param pHandler platform-specific way to invoke operations on VM
      * @param delayInMs wait that many ms before fetching the properties
      ** @return the agent URL if it is was set by a previous 'start' command.
      */
-    protected String checkAgentUrl(Object pVm, int delayInMs) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
+    protected String checkAgentUrl(Object pVm, VirtualMachineHandlerOperations pHandler, int delayInMs) {
         if (delayInMs != 0) {
             try {
                 Thread.sleep(delayInMs);
             } catch (InterruptedException e) {
                 // just continue
             }
         }
-        Properties systemProperties = getAgentSystemProperties(pVm);
+        Properties systemProperties = getAgentSystemProperties(pVm, pHandler);
         return systemProperties.getProperty(JvmAgent.JOLOKIA_AGENT_URL);
     }
 
     /**
      * Execute {@link com.sun.tools.attach.VirtualMachine#getSystemProperties()} via reflection
      * @param pVm the VirtualMachine object, typeless
+     * @param pHandler platform-specific way to invoke operations on VM
      * @return the system properties
      */
-    protected Properties getAgentSystemProperties(Object pVm) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
-        Class clazz = pVm.getClass();
-        Method method = clazz.getMethod("getSystemProperties");
-        return (Properties) method.invoke(pVm);
+    protected Properties getAgentSystemProperties(Object pVm, VirtualMachineHandlerOperations pHandler) {
+        return pHandler.getSystemProperties(pVm);
     }
 
     /**
      * Get a description of the process attached, either the numeric id only or, if a pattern is given,
      * the pattern and the associated PID
      *
-     * @param pOpts options from where to take the PID or pattern
      * @param pHandler handler for looking up the process in case of a pattern lookup
+     * @param pOpts options from where to take the PID or pattern
      * @return a description of the process
      */
-    protected String getProcessDescription(OptionsAndArgs pOpts, VirtualMachineHandler pHandler) {
+    protected String getProcessDescription(VirtualMachineHandlerOperations pHandler, OptionsAndArgs pOpts) {
         if (pOpts.getPid() != null) {
             return "PID " + pOpts.getPid();
         } else if (pOpts.getProcessPattern() != null) {
             StringBuffer desc = new StringBuffer("process matching \"")
                     .append(pOpts.getProcessPattern().pattern())
                     .append("\"");
-            try {
-                desc.append(" (PID: ")
-                        .append(pHandler.findProcess(pOpts.getProcessPattern()).getId())
-                        .append(")");
-            } catch (InvocationTargetException e) {
-                // ignored
-            } catch (NoSuchMethodException e) {
-                // ignored
-            } catch (IllegalAccessException e) {
-                // ignored
-            }
+            desc.append(" (PID: ")
+                    .append(pHandler.findProcess(pOpts.getProcessPattern()).getId())
+                    .append(")");
             return desc.toString();
         } else {
             return "(null)";

agent/jvm/src/main/java/org/jolokia/jvmagent/client/command/CommandDispatcher.java

@@ -20,7 +20,7 @@
 import java.util.*;
 
 import org.jolokia.jvmagent.client.util.OptionsAndArgs;
-import org.jolokia.jvmagent.client.util.VirtualMachineHandler;
+import org.jolokia.jvmagent.client.util.VirtualMachineHandlerOperations;
 
 /**
  * Dispatch for various attach commands
@@ -69,7 +69,7 @@ public CommandDispatcher(OptionsAndArgs pOptions) {
      * @param pHandler  handler for listing processes
      * @return the return code (0 or 1)
      */
-    public int dispatchCommand(Object pVm,VirtualMachineHandler pHandler) throws InvocationTargetException, NoSuchMethodException, IllegalAccessException {
+    public int dispatchCommand(Object pVm, VirtualMachineHandlerOperations pHandler) throws InvocationTargetException, NoSuchMethodException, IllegalAccessException {
         String commandName = options.getCommand();
         AbstractBaseCommand command = COMMANDS.get(commandName);
         if (command == null) {

agent/jvm/src/main/java/org/jolokia/jvmagent/client/command/EncryptCommand.java

@@ -1,7 +1,7 @@
 package org.jolokia.jvmagent.client.command;
 
 import org.jolokia.jvmagent.client.util.OptionsAndArgs;
-import org.jolokia.jvmagent.client.util.VirtualMachineHandler;
+import org.jolokia.jvmagent.client.util.VirtualMachineHandlerOperations;
 import org.jolokia.util.*;
 
 import java.io.*;
@@ -34,8 +34,8 @@ String getName() {
     }
 
     @Override
-    int execute(OptionsAndArgs pOpts, Object pVm, VirtualMachineHandler pHandler)
-            throws InvocationTargetException, NoSuchMethodException, IllegalAccessException {
+    int execute(OptionsAndArgs pOpts, Object pVm, VirtualMachineHandlerOperations pHandler)
+            throws InvocationTargetException {
         try {
             List<String> args = pOpts.getExtraArgs();
             String password = args.size() == 0 ?

agent/jvm/src/main/java/org/jolokia/jvmagent/client/command/HelpCommand.java

@@ -21,7 +21,7 @@
 import org.jolokia.Version;
 import org.jolokia.config.ConfigKey;
 import org.jolokia.jvmagent.client.util.OptionsAndArgs;
-import org.jolokia.jvmagent.client.util.VirtualMachineHandler;
+import org.jolokia.jvmagent.client.util.VirtualMachineHandlerOperations;
 
 /**
  * Print out usage information
@@ -40,7 +40,7 @@ String getName() {
 
     /** {@inheritDoc} */
     @Override
-    int execute(OptionsAndArgs pOpts, Object pVm, VirtualMachineHandler pHandler) throws InvocationTargetException, NoSuchMethodException, IllegalAccessException {
+    int execute(OptionsAndArgs pOpts, Object pVm, VirtualMachineHandlerOperations pHandler) throws InvocationTargetException, NoSuchMethodException, IllegalAccessException {
         printUsage();
         return 0;
     }

agent/jvm/src/main/java/org/jolokia/jvmagent/client/command/ListCommand.java

@@ -21,7 +21,6 @@
 import java.util.List;
 
 import org.jolokia.jvmagent.client.util.*;
-import org.jolokia.jvmagent.client.util.VirtualMachineHandler;
 
 /**
  * List all available Java processes
@@ -40,7 +39,7 @@ String getName() {
     /** {@inheritDoc} */
     @Override
     @SuppressWarnings("PMD.SystemPrintln")
-    int execute(OptionsAndArgs pOpts, Object pVm, VirtualMachineHandler pHandler) throws InvocationTargetException, NoSuchMethodException, IllegalAccessException {
+    int execute(OptionsAndArgs pOpts, Object pVm, VirtualMachineHandlerOperations pHandler) throws InvocationTargetException, NoSuchMethodException, IllegalAccessException {
         List<ProcessDescription> vmDescriptors = pHandler.listProcesses();
         for (ProcessDescription descriptor : vmDescriptors) {
             Formatter formatter = new Formatter().format("%7.7s   %-100.100s",

agent/jvm/src/main/java/org/jolokia/jvmagent/client/command/StartCommand.java

@@ -16,10 +16,8 @@
  * limitations under the License.
  */
 
-import java.lang.reflect.InvocationTargetException;
-
 import org.jolokia.jvmagent.client.util.OptionsAndArgs;
-import org.jolokia.jvmagent.client.util.VirtualMachineHandler;
+import org.jolokia.jvmagent.client.util.VirtualMachineHandlerOperations;
 
 /**
  * Load a Jolokia Agent and start it. Whether an agent is started is decided by the existence of the
@@ -30,41 +28,40 @@
  */
 public class StartCommand extends AbstractBaseCommand {
 
-    @Override
     /** {@inheritDoc} */
+    @Override
     String getName() {
         return "start";
     }
 
     /** {@inheritDoc} */
     @Override
     @SuppressWarnings("PMD.SystemPrintln")
-    int execute(OptionsAndArgs pOpts, Object pVm, VirtualMachineHandler pHandler)
-        throws InvocationTargetException, NoSuchMethodException, IllegalAccessException {
+    int execute(OptionsAndArgs pOpts, Object pVm, VirtualMachineHandlerOperations pHandler) {
         String agentUrl;
-        agentUrl = checkAgentUrl(pVm);
+        agentUrl = checkAgentUrl(pVm, pHandler);
         boolean quiet = pOpts.isQuiet();
         if (agentUrl == null) {
-            loadAgent(pVm, pOpts);
-            agentUrl = checkAgentUrl(pVm);
+            loadAgent(pVm, pHandler, pOpts);
+            agentUrl = checkAgentUrl(pVm, pHandler);
             if (agentUrl == null) {
                 // Wait a bit and try again
-                agentUrl = checkAgentUrl(pVm, 500);
+                agentUrl = checkAgentUrl(pVm, pHandler, 500);
                 if (agentUrl == null) {
-                    System.err.println("Couldn't start agent for " + getProcessDescription(pOpts, pHandler));
+                    System.err.println("Couldn't start agent for " + getProcessDescription(pHandler, pOpts));
                     System.err.println("Possible reason could be that port '" + pOpts.getPort() + "' is already occupied.");
                     System.err.println("Please check the standard output of the target process for a detailed error message.");
                     return 1;
                 }
             }
             if (!quiet) {
-                System.out.println("Started Jolokia for " + getProcessDescription(pOpts,pHandler));
+                System.out.println("Started Jolokia for " + getProcessDescription(pHandler, pOpts));
                 System.out.println(agentUrl);
             }
             return 0;
         } else {
             if (!quiet) {
-                System.out.println("Jolokia is already attached to " + getProcessDescription(pOpts,pHandler));
+                System.out.println("Jolokia is already attached to " + getProcessDescription(pHandler, pOpts));
                 System.out.println(agentUrl);
             }
             return 1;

agent/jvm/src/main/java/org/jolokia/jvmagent/client/command/StatusCommand.java

@@ -19,7 +19,7 @@
 import java.lang.reflect.InvocationTargetException;
 
 import org.jolokia.jvmagent.client.util.OptionsAndArgs;
-import org.jolokia.jvmagent.client.util.VirtualMachineHandler;
+import org.jolokia.jvmagent.client.util.VirtualMachineHandlerOperations;
 
 /**
  * Check the status of an agent on the target process.  Prints out the information
@@ -39,23 +39,24 @@ String getName() {
     /**
      * Checkt the status and print it out (except for <code>--quiet</code>
      * @param pVm the virtual machine
+     * @param pHandler platform-specific way to invoke operations on VM
      * @return the exit code (0: agent is attached, 1: agent is not attached.)
      */
     @Override
     @SuppressWarnings("PMD.SystemPrintln")
-    int execute(OptionsAndArgs pOptions, Object pVm, VirtualMachineHandler pHandler)
+    int execute(OptionsAndArgs pOptions, Object pVm, VirtualMachineHandlerOperations pHandler)
             throws InvocationTargetException, NoSuchMethodException, IllegalAccessException {
-        String agentUrl = checkAgentUrl(pVm);
+        String agentUrl = checkAgentUrl(pVm, pHandler);
         boolean quiet = pOptions.isQuiet();
         if (agentUrl != null) {
             if (!quiet) {
-                System.out.println("Jolokia started for " + getProcessDescription(pOptions,pHandler));
+                System.out.println("Jolokia started for " + getProcessDescription(pHandler, pOptions));
                 System.out.println(agentUrl);
             }
             return 0;
         } else {
             if (!quiet) {
-                System.out.println("No Jolokia agent attached to " + getProcessDescription(pOptions,pHandler));
+                System.out.println("No Jolokia agent attached to " + getProcessDescription(pHandler, pOptions));
             }
             return 1;
         }

agent/jvm/src/main/java/org/jolokia/jvmagent/client/command/StopCommand.java

@@ -19,7 +19,7 @@
 import java.lang.reflect.InvocationTargetException;
 
 import org.jolokia.jvmagent.client.util.OptionsAndArgs;
-import org.jolokia.jvmagent.client.util.VirtualMachineHandler;
+import org.jolokia.jvmagent.client.util.VirtualMachineHandlerOperations;
 
 /**
  * Stop a Jolokia Agent, but only if it is already running (started with 'start').
@@ -40,18 +40,18 @@ String getName() {
     /** {@inheritDoc} */
     @Override
     @SuppressWarnings("PMD.SystemPrintln")
-    int execute(OptionsAndArgs pOpts, Object pVm, VirtualMachineHandler pHandler) throws InvocationTargetException, NoSuchMethodException, IllegalAccessException {
-        String agentUrl = checkAgentUrl(pVm);
+    int execute(OptionsAndArgs pOpts, Object pVm, VirtualMachineHandlerOperations pHandler) throws InvocationTargetException, NoSuchMethodException, IllegalAccessException {
+        String agentUrl = checkAgentUrl(pVm, pHandler);
         boolean quiet = pOpts.isQuiet();
         if (agentUrl != null) {
-            loadAgent(pVm,pOpts,"mode=stop");
+            loadAgent(pVm, pHandler, pOpts, "mode=stop");
             if (!quiet) {
-                System.out.println("Stopped Jolokia for " + getProcessDescription(pOpts,pHandler));
+                System.out.println("Stopped Jolokia for " + getProcessDescription(pHandler, pOpts));
             }
             return 0;
         } else {
             if (!quiet) {
-                System.out.println("Jolokia is not attached to " + getProcessDescription(pOpts,pHandler));
+                System.out.println("Jolokia is not attached to " + getProcessDescription(pHandler, pOpts));
             }
             return 1;
         }