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-rw-r--r--kamon-autoweave/src/main/java/com/sun/tools/attach/AgentInitializationException.java90
-rw-r--r--kamon-autoweave/src/main/java/com/sun/tools/attach/AgentLoadException.java55
-rw-r--r--kamon-autoweave/src/main/java/com/sun/tools/attach/AttachNotSupportedException.java56
-rw-r--r--kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachine.java527
-rw-r--r--kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachineDescriptor.java208
-rw-r--r--kamon-autoweave/src/main/java/com/sun/tools/attach/spi/AttachProvider.java240
6 files changed, 1176 insertions, 0 deletions
diff --git a/kamon-autoweave/src/main/java/com/sun/tools/attach/AgentInitializationException.java b/kamon-autoweave/src/main/java/com/sun/tools/attach/AgentInitializationException.java
new file mode 100644
index 00000000..c31ab371
--- /dev/null
+++ b/kamon-autoweave/src/main/java/com/sun/tools/attach/AgentInitializationException.java
@@ -0,0 +1,90 @@
+/*
+ * Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+package com.sun.tools.attach;
+
+/**
+ * The exception thrown when an agent fails to initialize in the target Java virtual machine.
+ * <p/>
+ * <p> This exception is thrown by {@link
+ * VirtualMachine#loadAgent VirtualMachine.loadAgent},
+ * {@link VirtualMachine#loadAgentLibrary
+ * VirtualMachine.loadAgentLibrary}, {@link
+ * VirtualMachine#loadAgentPath VirtualMachine.loadAgentPath}
+ * methods if an agent, or agent library, cannot be initialized.
+ * When thrown by <tt>VirtualMachine.loadAgentLibrary</tt>, or
+ * <tt>VirtualMachine.loadAgentPath</tt> then the exception encapsulates
+ * the error returned by the agent's <code>Agent_OnAttach</code> function.
+ * This error code can be obtained by invoking the {@link #returnValue() returnValue} method.
+ */
+public final class AgentInitializationException extends Exception
+{
+ private static final long serialVersionUID = -1508756333332806353L;
+
+ private final int returnValue;
+
+ /**
+ * Constructs an <code>AgentInitializationException</code> with
+ * no detail message.
+ */
+ public AgentInitializationException()
+ {
+ returnValue = 0;
+ }
+
+ /**
+ * Constructs an <code>AgentInitializationException</code> with the specified detail message.
+ *
+ * @param s the detail message.
+ */
+ public AgentInitializationException(String s)
+ {
+ super(s);
+ returnValue = 0;
+ }
+
+ /**
+ * Constructs an <code>AgentInitializationException</code> with
+ * the specified detail message and the return value from the
+ * execution of the agent's <code>Agent_OnAttach</code> function.
+ *
+ * @param s the detail message.
+ * @param returnValue the return value
+ */
+ public AgentInitializationException(String s, int returnValue)
+ {
+ super(s);
+ this.returnValue = returnValue;
+ }
+
+ /**
+ * If the exception was created with the return value from the agent
+ * <code>Agent_OnAttach</code> function then this returns that value,
+ * otherwise returns <code>0</code>. </p>
+ */
+ public int returnValue()
+ {
+ return returnValue;
+ }
+}
diff --git a/kamon-autoweave/src/main/java/com/sun/tools/attach/AgentLoadException.java b/kamon-autoweave/src/main/java/com/sun/tools/attach/AgentLoadException.java
new file mode 100644
index 00000000..816255a5
--- /dev/null
+++ b/kamon-autoweave/src/main/java/com/sun/tools/attach/AgentLoadException.java
@@ -0,0 +1,55 @@
+/*
+ * Copyright 2005 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+package com.sun.tools.attach;
+
+/**
+ * The exception thrown when an agent cannot be loaded into the target Java virtual machine.
+ * <p/>
+ * <p> This exception is thrown by {@link
+ * VirtualMachine#loadAgent VirtualMachine.loadAgent} or
+ * {@link VirtualMachine#loadAgentLibrary
+ * VirtualMachine.loadAgentLibrary}, {@link VirtualMachine#loadAgentPath loadAgentPath} methods
+ * if the agent, or agent library, cannot be loaded.
+ */
+public final class AgentLoadException extends Exception
+{
+ private static final long serialVersionUID = 688047862952114238L;
+
+ /**
+ * Constructs an <code>AgentLoadException</code> with
+ * no detail message.
+ */
+ public AgentLoadException()
+ {
+ }
+
+ /**
+ * Constructs an <code>AgentLoadException</code> with the specified detail message.
+ */
+ public AgentLoadException(String s)
+ {
+ super(s);
+ }
+}
diff --git a/kamon-autoweave/src/main/java/com/sun/tools/attach/AttachNotSupportedException.java b/kamon-autoweave/src/main/java/com/sun/tools/attach/AttachNotSupportedException.java
new file mode 100644
index 00000000..7b59e6e2
--- /dev/null
+++ b/kamon-autoweave/src/main/java/com/sun/tools/attach/AttachNotSupportedException.java
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2005 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+package com.sun.tools.attach;
+
+/**
+ * Thrown by {@link VirtualMachine#attach VirtalMachine.attach} when attempting to attach to a Java
+ * virtual machine for which a compatible {@link com.sun.tools.attach.spi.AttachProvider
+ * AttachProvider} does not exist. It is also thrown by {@link
+ * com.sun.tools.attach.spi.AttachProvider#attachVirtualMachine
+ * AttachProvider.attachVirtualMachine} if the provider attempts to
+ * attach to a Java virtual machine with which it not compatible.
+ */
+public final class AttachNotSupportedException extends Exception
+{
+ private static final long serialVersionUID = 3391824968260177264L;
+
+ /**
+ * Constructs an <code>AttachNotSupportedException</code> with no detail message.
+ */
+ public AttachNotSupportedException()
+ {
+ }
+
+ /**
+ * Constructs an <code>AttachNotSupportedException</code> with
+ * the specified detail message.
+ *
+ * @param s the detail message.
+ */
+ public AttachNotSupportedException(String s)
+ {
+ super(s);
+ }
+}
diff --git a/kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachine.java b/kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachine.java
new file mode 100644
index 00000000..e1f010f8
--- /dev/null
+++ b/kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachine.java
@@ -0,0 +1,527 @@
+/*
+ * Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+package com.sun.tools.attach;
+
+import com.sun.tools.attach.spi.AttachProvider;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Properties;
+
+/**
+ * A Java virtual machine.
+ * <p/>
+ * <p> A <code>VirtualMachine</code> represents a Java virtual machine to which this
+ * Java virtual machine has attached. The Java virtual machine to which it is
+ * attached is sometimes called the <i>target virtual machine</i>, or <i>target VM</i>.
+ * An application (typically a tool such as a managemet console or profiler) uses a
+ * VirtualMachine to load an agent into the target VM. For example, a profiler tool
+ * written in the Java Language might attach to a running application and load its
+ * profiler agent to profile the running application. </p>
+ * <p/>
+ * <p> A VirtualMachine is obtained by invoking the {@link #attach(String) attach} method
+ * with an identifier that identifies the target virtual machine. The identifier is
+ * implementation-dependent but is typically the process identifier (or pid) in
+ * environments where each Java virtual machine runs in its own operating system process.
+ * Alternatively, a <code>VirtualMachine</code> instance is obtained by invoking the
+ * {@link #attach(VirtualMachineDescriptor) attach} method with a {@link
+ * com.sun.tools.attach.VirtualMachineDescriptor VirtualMachineDescriptor} obtained
+ * from the list of virtual machine descriptors returned by the {@link #list list} method.
+ * Once a reference to a virtual machine is obtained, the {@link #loadAgent loadAgent},
+ * {@link #loadAgentLibrary loadAgentLibrary}, and {@link #loadAgentPath loadAgentPath}
+ * methods are used to load agents into target virtual machine. The {@link
+ * #loadAgent loadAgent} method is used to load agents that are written in the Java
+ * Language and deployed in a {@link java.util.jar.JarFile JAR file}. (See
+ * {@link java.lang.instrument} for a detailed description on how these agents
+ * are loaded and started). The {@link #loadAgentLibrary loadAgentLibrary} and
+ * {@link #loadAgentPath loadAgentPath} methods are used to load agents that
+ * are deployed in a dynamic library and make use of the <a
+ * href="../../../../../../../../technotes/guides/jvmti/index.html">JVM Tools
+ * Interface</a>. </p>
+ * <p/>
+ * <p> In addition to loading agents a VirtualMachine provides read access to the
+ * {@link java.lang.System#getProperties() system properties} in the target VM.
+ * This can be useful in some environments where properties such as
+ * <code>java.home</code>, <code>os.name</code>, or <code>os.arch</code> are
+ * used to construct the path to agent that will be loaded into the target VM.
+ * <p/>
+ * <p> The following example demonstrates how VirtualMachine may be used:</p>
+ * <p/>
+ * <pre>
+ * <p/>
+ * // attach to target VM
+ * VirtualMachine vm = VirtualMachine.attach("2177");
+ * <p/>
+ * // get system properties in target VM
+ * Properties props = vm.getSystemProperties();
+ * <p/>
+ * // construct path to management agent
+ * String home = props.getProperty("java.home");
+ * String agent = home + File.separator + "lib" + File.separator
+ * + "management-agent.jar";
+ * <p/>
+ * // load agent into target VM
+ * vm.loadAgent(agent, "com.sun.management.jmxremote.port=5000");
+ * <p/>
+ * // detach
+ * vm.detach();
+ * <p/>
+ * </pre>
+ * <p/>
+ * <p> In this example we attach to a Java virtual machine that is identified by
+ * the process identifier <code>2177</code>. The system properties from the target
+ * VM are then used to construct the path to a <i>management agent</i> which is then
+ * loaded into the target VM. Once loaded the client detaches from the target VM. </p>
+ * <p/>
+ * <p> A VirtualMachine is safe for use by multiple concurrent threads. </p>
+ *
+ * @since 1.6
+ */
+public abstract class VirtualMachine
+{
+ private final AttachProvider provider;
+ private final String id;
+ private volatile int hash; // 0 => not computed
+
+ /**
+ * Initializes a new instance of this class.
+ *
+ * @param provider The attach provider creating this class.
+ * @param id The abstract identifier that identifies the Java virtual machine.
+ */
+ protected VirtualMachine(AttachProvider provider, String id)
+ {
+ this.provider = provider;
+ this.id = id;
+ }
+
+ /**
+ * Return a list of Java virtual machines.
+ * <p/>
+ * This method returns a list of Java {@link com.sun.tools.attach.VirtualMachineDescriptor}
+ * elements. The list is an aggregation of the virtual machine descriptor lists obtained by
+ * invoking the {@link com.sun.tools.attach.spi.AttachProvider#listVirtualMachines
+ * listVirtualMachines} method of all installed {@link com.sun.tools.attach.spi.AttachProvider
+ * attach providers}. If there are no Java virtual machines known to any provider then an empty
+ * list is returned.
+ *
+ * @return The list of virtual machine descriptors.
+ */
+ public static List<VirtualMachineDescriptor> list()
+ {
+ List<VirtualMachineDescriptor> l = new ArrayList<VirtualMachineDescriptor>();
+ List<AttachProvider> providers = AttachProvider.providers();
+
+ for (AttachProvider provider : providers) {
+ l.addAll(provider.listVirtualMachines());
+ }
+
+ return l;
+ }
+
+ /**
+ * Attaches to a Java virtual machine.
+ * <p/>
+ * This method obtains the list of attach providers by invoking the
+ * {@link com.sun.tools.attach.spi.AttachProvider#providers() AttachProvider.providers()} method.
+ * It then iterates overs the list and invokes each provider's {@link
+ * com.sun.tools.attach.spi.AttachProvider#attachVirtualMachine(java.lang.String)
+ * attachVirtualMachine} method in turn. If a provider successfully
+ * attaches then the iteration terminates, and the VirtualMachine created
+ * by the provider that successfully attached is returned by this method.
+ * If the <code>attachVirtualMachine</code> method of all providers throws
+ * {@link com.sun.tools.attach.AttachNotSupportedException AttachNotSupportedException}
+ * then this method also throws <code>AttachNotSupportedException</code>.
+ * This means that <code>AttachNotSupportedException</code> is thrown when
+ * the identifier provided to this method is invalid, or the identifier
+ * corresponds to a Java virtual machine that does not exist, or none
+ * of the providers can attach to it. This exception is also thrown if
+ * {@link com.sun.tools.attach.spi.AttachProvider#providers()
+ * AttachProvider.providers()} returns an empty list. </p>
+ *
+ * @param id The abstract identifier that identifies the Java virtual machine.
+ * @return A VirtualMachine representing the target VM.
+ * @throws SecurityException If a security manager has been installed and it denies
+ * {@link com.sun.tools.attach.AttachPermission AttachPermission}
+ * <tt>("attachVirtualMachine")</tt>, or another permission
+ * required by the implementation.
+ * @throws IOException If an I/O error occurs
+ */
+ public static VirtualMachine attach(String id) throws AttachNotSupportedException, IOException
+ {
+ List<AttachProvider> providers = AttachProvider.providers();
+ AttachNotSupportedException lastExc = null;
+
+ for (AttachProvider provider : providers) {
+ try {
+ return provider.attachVirtualMachine(id);
+ }
+ catch (AttachNotSupportedException x) {
+ lastExc = x;
+ }
+ }
+
+ throw lastExc;
+ }
+
+ /**
+ * Attaches to a Java virtual machine.
+ * <p/>
+ * This method first invokes the {@link com.sun.tools.attach.VirtualMachineDescriptor#provider()
+ * provider()} method of the given virtual machine descriptor to obtain the attach provider.
+ * It then invokes the attach provider's {@link
+ * com.sun.tools.attach.spi.AttachProvider#attachVirtualMachine(VirtualMachineDescriptor)
+ * attachVirtualMachine} to attach to the target VM.
+ *
+ * @param vmd The virtual machine descriptor.
+ *
+ * @return A VirtualMachine representing the target VM.
+ *
+ * @throws SecurityException
+ * If a security manager has been installed and it denies
+ * {@link com.sun.tools.attach.AttachPermission AttachPermission}
+ * <tt>("attachVirtualMachine")</tt>, or another permission
+ * required by the implementation.
+ *
+ * @throws AttachNotSupportedException
+ * If the attach provider's <code>attachVirtualmachine</code>
+ * throws <code>AttachNotSupportedException</code>.
+ *
+ * @throws IOException If an I/O error occurs
+ *
+ * @throws NullPointerException If <code>vmd</code> is <code>null</code>.
+ */
+ public static VirtualMachine attach(VirtualMachineDescriptor vmd)
+ throws AttachNotSupportedException, IOException
+ {
+ return vmd.provider().attachVirtualMachine(vmd);
+ }
+
+ /**
+ * Detach from the virtual machine.
+ * <p/>
+ * After detaching from the virtual machine, any further attempt to invoke
+ * operations on that virtual machine will cause an {@link java.io.IOException
+ * IOException} to be thrown. If an operation (such as {@link #loadAgent
+ * loadAgent} for example) is in progress when this method is invoked then
+ * the behaviour is implementation dependent. In other words, it is
+ * implementation specific if the operation completes or throws <tt>IOException</tt>.
+ * <p/>
+ * If already detached from the virtual machine then invoking this method has no effect.
+ *
+ * @throws IOException If an I/O error occurs
+ */
+ public abstract void detach() throws IOException;
+
+ /**
+ * Returns the provider that created this virtual machine.
+ */
+ public final AttachProvider provider()
+ {
+ return provider;
+ }
+
+ /**
+ * Returns the identifier for this Java virtual machine.
+ */
+ public final String id()
+ {
+ return id;
+ }
+
+ /**
+ * Loads an agent library.
+ * <p/>
+ * A <a href="../../../../../../../../technotes/guides/jvmti/index.html">JVM
+ * TI</a> client is called an <i>agent</i>. It is developed in a native language.
+ * A JVM TI agent is deployed in a platform specific manner but it is typically the
+ * platform equivalent of a dynamic library. This method causes the given agent
+ * library to be loaded into the target VM (if not already loaded).
+ * It then causes the target VM to invoke the <code>Agent_OnAttach</code> function
+ * as specified in the
+ * <a href="../../../../../../../../technotes/guides/jvmti/index.html"> JVM Tools
+ * Interface</a> specification. Note that the <code>Agent_OnAttach</code>
+ * function is invoked even if the agent library was loaded prior to invoking
+ * this method.
+ * <p/>
+ * The agent library provided is the name of the agent library. It is interpreted
+ * in the target virtual machine in an implementation-dependent manner. Typically an
+ * implementation will expand the library name into an operating system specific file
+ * name. For example, on UNIX systems, the name <tt>foo</tt> might be expanded to
+ * <tt>libfoo.so</tt>, and located using the search path specified by the
+ * <tt>LD_LIBRARY_PATH</tt> environment variable.
+ * <p/>
+ * If the <code>Agent_OnAttach</code> function in the agent library returns
+ * an error then an {@link com.sun.tools.attach.AgentInitializationException} is
+ * thrown. The return value from the <code>Agent_OnAttach</code> can then be
+ * obtained by invoking the {@link
+ * com.sun.tools.attach.AgentInitializationException#returnValue() returnValue}
+ * method on the exception.
+ *
+ * @param agentLibrary The name of the agent library.
+ * @param options The options to provide to the <code>Agent_OnAttach</code>
+ * function (can be <code>null</code>).
+ * @throws AgentLoadException If the agent library does not exist, or cannot be loaded for
+ * another reason.
+ * @throws AgentInitializationException If the <code>Agent_OnAttach</code> function returns an error
+ * @throws IOException If an I/O error occurs
+ * @throws NullPointerException If <code>agentLibrary</code> is <code>null</code>.
+ * @see com.sun.tools.attach.AgentInitializationException#returnValue()
+ */
+ public abstract void loadAgentLibrary(String agentLibrary, String options)
+ throws AgentLoadException, AgentInitializationException, IOException;
+
+ /**
+ * Loads an agent library.
+ * <p/>
+ * This convenience method works as if by invoking:
+ * <p/>
+ * <blockquote><tt>
+ * {@link #loadAgentLibrary(String, String) loadAgentLibrary}(agentLibrary,&nbsp;null);
+ * </tt></blockquote>
+ *
+ * @param agentLibrary The name of the agent library.
+ * @throws AgentLoadException If the agent library does not exist, or cannot be loaded for
+ * another reason.
+ * @throws AgentInitializationException If the <code>Agent_OnAttach</code> function returns an error
+ * @throws IOException If an I/O error occurs
+ * @throws NullPointerException If <code>agentLibrary</code> is <code>null</code>.
+ */
+ public void loadAgentLibrary(String agentLibrary)
+ throws AgentLoadException, AgentInitializationException, IOException
+ {
+ loadAgentLibrary(agentLibrary, null);
+ }
+
+ /**
+ * Load a native agent library by full pathname.
+ * <p/>
+ * A <a href="../../../../../../../../technotes/guides/jvmti/index.html">JVM TI</a> client is
+ * called an <i>agent</i>. It is developed in a native language.
+ * A JVM TI agent is deployed in a platform specific manner but it is typically the
+ * platform equivalent of a dynamic library. This method causes the given agent
+ * library to be loaded into the target VM (if not already loaded).
+ * It then causes the target VM to invoke the <code>Agent_OnAttach</code> function
+ * as specified in the
+ * <a href="../../../../../../../../technotes/guides/jvmti/index.html"> JVM Tools
+ * Interface</a> specification. Note that the <code>Agent_OnAttach</code>
+ * function is invoked even if the agent library was loaded prior to invoking
+ * this method.
+ * <p/>
+ * The agent library provided is the absolute path from which to load the
+ * agent library. Unlike {@link #loadAgentLibrary loadAgentLibrary}, the library name
+ * is not expanded in the target virtual machine.
+ * <p/>
+ * If the <code>Agent_OnAttach</code> function in the agent library returns
+ * an error then an {@link com.sun.tools.attach.AgentInitializationException} is
+ * thrown. The return value from the <code>Agent_OnAttach</code> can then be
+ * obtained by invoking the {@link
+ * com.sun.tools.attach.AgentInitializationException#returnValue() returnValue}
+ * method on the exception.
+ *
+ * @param agentPath The full path of the agent library.
+ * @param options The options to provide to the <code>Agent_OnAttach</code>
+ * function (can be <code>null</code>).
+ * @throws AgentLoadException If the agent library does not exist, or cannot be loaded for
+ * another reason.
+ * @throws AgentInitializationException If the <code>Agent_OnAttach</code> function returns an error
+ * @throws IOException If an I/O error occurs
+ * @throws NullPointerException If <code>agentPath</code> is <code>null</code>.
+ * @see com.sun.tools.attach.AgentInitializationException#returnValue()
+ */
+ public abstract void loadAgentPath(String agentPath, String options)
+ throws AgentLoadException, AgentInitializationException, IOException;
+
+ /**
+ * Load a native agent library by full pathname.
+ * <p/>
+ * This convenience method works as if by invoking:
+ * <p/>
+ * <blockquote><tt>
+ * {@link #loadAgentPath(String, String) loadAgentPath}(agentLibrary,&nbsp;null);
+ * </tt></blockquote>
+ *
+ * @param agentPath The full path to the agent library.
+ * @throws AgentLoadException If the agent library does not exist, or cannot be loaded for
+ * another reason.
+ * @throws AgentInitializationException If the <code>Agent_OnAttach</code> function returns an error
+ * @throws IOException If an I/O error occurs
+ * @throws NullPointerException If <code>agentPath</code> is <code>null</code>.
+ */
+ public void loadAgentPath(String agentPath)
+ throws AgentLoadException, AgentInitializationException, IOException
+ {
+ loadAgentPath(agentPath, null);
+ }
+
+
+ /**
+ * Loads an agent.
+ * <p/>
+ * <p> The agent provided to this method is a path name to a JAR file on the file
+ * system of the target virtual machine. This path is passed to the target virtual
+ * machine where it is interpreted. The target virtual machine attempts to start
+ * the agent as specified by the {@link java.lang.instrument} specification.
+ * That is, the specified JAR file is added to the system class path (of the target
+ * virtual machine), and the <code>agentmain</code> method of the agent class, specified
+ * by the <code>Agent-Class</code> attribute in the JAR manifest, is invoked. This
+ * method completes when the <code>agentmain</code> method completes.
+ *
+ * @param agent Path to the JAR file containing the agent.
+ * @param options The options to provide to the agent's <code>agentmain</code>
+ * method (can be <code>null</code>).
+ * @throws AgentLoadException If the agent does not exist, or cannot be started in the manner
+ * specified in the {@link java.lang.instrument} specification.
+ * @throws AgentInitializationException If the <code>agentmain</code> throws an exception
+ * @throws IOException If an I/O error occurs
+ * @throws NullPointerException If <code>agent</code> is <code>null</code>.
+ */
+ public abstract void loadAgent(String agent, String options)
+ throws AgentLoadException, AgentInitializationException, IOException;
+
+ /**
+ * Loads an agent.
+ * <p/>
+ * This convenience method works as if by invoking:
+ * <p/>
+ * <blockquote><tt>
+ * {@link #loadAgent(String, String) loadAgent}(agent,&nbsp;null);
+ * </tt></blockquote>
+ *
+ * @param agent Path to the JAR file containing the agent.
+ * @throws AgentLoadException If the agent does not exist, or cannot be started in the manner
+ * specified in the {@link java.lang.instrument} specification.
+ * @throws AgentInitializationException If the <code>agentmain</code> throws an exception
+ * @throws IOException If an I/O error occurs
+ * @throws NullPointerException If <code>agent</code> is <code>null</code>.
+ */
+ public void loadAgent(String agent)
+ throws AgentLoadException, AgentInitializationException, IOException
+ {
+ loadAgent(agent, null);
+ }
+
+ /**
+ * Returns the current system properties in the target virtual machine.
+ * <p/>
+ * This method returns the system properties in the target virtual
+ * machine. Properties whose key or value is not a <tt>String</tt> are
+ * omitted. The method is approximately equivalent to the invocation of the
+ * method {@link java.lang.System#getProperties System.getProperties}
+ * in the target virtual machine except that properties with a key or
+ * value that is not a <tt>String</tt> are not included.
+ * <p/>
+ * This method is typically used to decide which agent to load into
+ * the target virtual machine with {@link #loadAgent loadAgent}, or
+ * {@link #loadAgentLibrary loadAgentLibrary}. For example, the
+ * <code>java.home</code> or <code>user.dir</code> properties might be
+ * use to create the path to the agent library or JAR file.
+ *
+ * @return The system properties
+ * @throws IOException If an I/O error occurs
+ * @see java.lang.System#getProperties
+ * @see #loadAgentLibrary
+ * @see #loadAgent
+ */
+ public abstract Properties getSystemProperties() throws IOException;
+
+ /**
+ * Returns the current <i>agent properties</i> in the target virtual
+ * machine.
+ * <p/>
+ * The target virtual machine can maintain a list of properties on
+ * behalf of agents. The manner in which this is done, the names of the
+ * properties, and the types of values that are allowed, is implementation
+ * specific. Agent properties are typically used to store communication
+ * end-points and other agent configuration details. For example, a debugger
+ * agent might create an agent property for its transport address.
+ * <p/>
+ * This method returns the agent properties whose key and value is a
+ * <tt>String</tt>. Properties whose key or value is not a <tt>String</tt>
+ * are omitted. If there are no agent properties maintained in the target
+ * virtual machine then an empty property list is returned.
+ *
+ * @return The agent properties
+ * @throws IOException If an I/O error occurs
+ */
+ public abstract Properties getAgentProperties() throws IOException;
+
+ /**
+ * Returns a hash-code value for this VirtualMachine. The hash
+ * code is based upon the VirtualMachine's components, and satisfies
+ * the general contract of the Object.hashCode method.
+ *
+ * @return A hash-code value for this virtual machine
+ */
+ public int hashCode()
+ {
+ if (hash != 0) {
+ return hash;
+ }
+
+ hash = provider.hashCode() * 127 + id.hashCode();
+ return hash;
+ }
+
+ /**
+ * Tests this VirtualMachine for equality with another object.
+ * <p/>
+ * <p> If the given object is not a VirtualMachine then this
+ * method returns <tt>false</tt>. For two VirtualMachines to
+ * be considered equal requires that they both reference the same
+ * provider, and their {@link VirtualMachineDescriptor#id() identifiers} are equal. </p>
+ * <p/>
+ * <p> This method satisfies the general contract of the {@link
+ * java.lang.Object#equals(Object) Object.equals} method. </p>
+ *
+ * @param ob The object to which this object is to be compared
+ * @return <tt>true</tt> if, and only if, the given object is
+ * a VirtualMachine that is equal to this
+ * VirtualMachine.
+ */
+ public boolean equals(Object ob)
+ {
+ if (ob == this) {
+ return true;
+ }
+
+ if (!(ob instanceof VirtualMachine)) {
+ return false;
+ }
+
+ VirtualMachine other = (VirtualMachine) ob;
+
+ return other.provider() == provider() && other.id().equals(id());
+ }
+
+ /**
+ * Returns the string representation of the <code>VirtualMachine</code>.
+ */
+ public String toString()
+ {
+ return provider.toString() + ": " + id;
+ }
+}
diff --git a/kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachineDescriptor.java b/kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachineDescriptor.java
new file mode 100644
index 00000000..6459e806
--- /dev/null
+++ b/kamon-autoweave/src/main/java/com/sun/tools/attach/VirtualMachineDescriptor.java
@@ -0,0 +1,208 @@
+/*
+ * Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+package com.sun.tools.attach;
+
+import com.sun.tools.attach.spi.AttachProvider;
+
+/**
+ * Describes a Java virtual machine.
+ * <p/>
+ * <p> A <code>VirtualMachineDescriptor</code> is a container class used to
+ * describe a Java virtual machine. It encapsulates an identifier that identifies
+ * a target virtual machine, and a reference to the {@link
+ * com.sun.tools.attach.spi.AttachProvider AttachProvider} that should be used
+ * when attempting to attach to the virtual machine. The identifier is
+ * implementation-dependent but is typically the process identifier (or pid)
+ * environments where each Java virtual machine runs in its own operating system
+ * process. </p>
+ * <p/>
+ * <p> A <code>VirtualMachineDescriptor</code> also has a {@link #displayName() displayName}.
+ * The display name is typically a human readable string that a tool might
+ * display to a user. For example, a tool that shows a list of Java
+ * virtual machines running on a system might use the display name rather
+ * than the identifier. A <code>VirtualMachineDescriptor</code> may be
+ * created without a <i>display name</i>. In that case the identifier is
+ * used as the <i>display name</i>.
+ * <p/>
+ * <p> <code>VirtualMachineDescriptor</code> instances are typically created by
+ * invoking the {@link VirtualMachine#list VirtualMachine.list()}
+ * method. This returns the complete list of descriptors to describe the
+ * Java virtual machines known to all installed {@link
+ * com.sun.tools.attach.spi.AttachProvider attach providers}.
+ *
+ * @since 1.6
+ */
+public final class VirtualMachineDescriptor
+{
+ private AttachProvider provider;
+ private String id;
+ private String displayName;
+
+ private volatile int hash; // 0 => not computed
+
+ /**
+ * Creates a virtual machine descriptor from the given components.
+ *
+ * @param provider The AttachProvider to attach to the Java virtual machine.
+ * @param id The virtual machine identifier.
+ * @param displayName The display name.
+ * @throws NullPointerException If any of the arguments are <code>null</code>
+ */
+ public VirtualMachineDescriptor(AttachProvider provider, String id, String displayName)
+ {
+ if (provider == null) {
+ throw new NullPointerException("provider cannot be null");
+ }
+
+ if (id == null) {
+ throw new NullPointerException("identifier cannot be null");
+ }
+
+ if (displayName == null) {
+ throw new NullPointerException("display name cannot be null");
+ }
+
+ this.provider = provider;
+ this.id = id;
+ this.displayName = displayName;
+ }
+
+ /**
+ * Creates a virtual machine descriptor from the given components.
+ * <p/>
+ * <p> This convenience constructor works as if by invoking the
+ * three-argument constructor as follows:
+ * <p/>
+ * <blockquote><tt>
+ * new&nbsp;{@link #VirtualMachineDescriptor(com.sun.tools.attach.spi.AttachProvider, String, String)
+ * VirtualMachineDescriptor}(provider, &nbsp;id, &nbsp;id);
+ * </tt></blockquote>
+ * <p/>
+ * <p> That is, it creates a virtual machine descriptor such that
+ * the <i>display name</i> is the same as the virtual machine
+ * identifier.
+ *
+ * @param provider The AttachProvider to attach to the Java virtual machine.
+ * @param id The virtual machine identifier.
+ * @throws NullPointerException If <tt>provider</tt> or <tt>id</tt> is <tt>null</tt>.
+ */
+ public VirtualMachineDescriptor(AttachProvider provider, String id)
+ {
+ this(provider, id, id);
+ }
+
+ /**
+ * Return the <code>AttachProvider</code> that this descriptor references.
+ *
+ * @return The <code>AttachProvider</code> that this descriptor references.
+ */
+ public AttachProvider provider()
+ {
+ return provider;
+ }
+
+ /**
+ * Return the identifier component of this descriptor.
+ *
+ * @return The identifier component of this descriptor.
+ */
+ public String id()
+ {
+ return id;
+ }
+
+ /**
+ * Return the <i>display name</i> component of this descriptor.
+ *
+ * @return The display name component of this descriptor.
+ */
+ public String displayName()
+ {
+ return displayName;
+ }
+
+ /**
+ * Returns a hash-code value for this VirtualMachineDescriptor. The hash
+ * code is based upon the descriptor's components, and satisfies
+ * the general contract of the Object.hashCode method.
+ *
+ * @return A hash-code value for this descriptor.
+ */
+ public int hashCode()
+ {
+ if (hash != 0) {
+ return hash;
+ }
+
+ hash = provider.hashCode() * 127 + id.hashCode();
+ return hash;
+ }
+
+ /**
+ * Tests this VirtualMachineDescriptor for equality with another object.
+ * <p/>
+ * <p> If the given object is not a VirtualMachineDescriptor then this
+ * method returns <tt>false</tt>. For two VirtualMachineDescriptors to
+ * be considered equal requires that they both reference the same
+ * provider, and their {@link #id() identifiers} are equal. </p>
+ * <p/>
+ * <p> This method satisfies the general contract of the {@link
+ * Object#equals(Object) Object.equals} method. </p>
+ *
+ * @param ob The object to which this object is to be compared
+ * @return <tt>true</tt> if, and only if, the given object is
+ * a VirtualMachineDescriptor that is equal to this
+ * VirtualMachineDescriptor.
+ */
+ public boolean equals(Object ob)
+ {
+ if (ob == this)
+ return true;
+ if (!(ob instanceof VirtualMachineDescriptor))
+ return false;
+ VirtualMachineDescriptor other = (VirtualMachineDescriptor) ob;
+ if (other.provider() != this.provider()) {
+ return false;
+ }
+ if (!other.id().equals(this.id())) {
+ return false;
+ }
+ return true;
+ }
+
+ /**
+ * Returns the string representation of the <code>VirtualMachineDescriptor</code>.
+ */
+ public String toString()
+ {
+ String s = provider.toString() + ": " + id;
+
+ if (displayName != id) {
+ s += " " + displayName;
+ }
+
+ return s;
+ }
+}
diff --git a/kamon-autoweave/src/main/java/com/sun/tools/attach/spi/AttachProvider.java b/kamon-autoweave/src/main/java/com/sun/tools/attach/spi/AttachProvider.java
new file mode 100644
index 00000000..98e8084d
--- /dev/null
+++ b/kamon-autoweave/src/main/java/com/sun/tools/attach/spi/AttachProvider.java
@@ -0,0 +1,240 @@
+/*
+ * Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+package com.sun.tools.attach.spi;
+
+import com.sun.tools.attach.AttachNotSupportedException;
+import com.sun.tools.attach.VirtualMachine;
+import com.sun.tools.attach.VirtualMachineDescriptor;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.ServiceLoader;
+
+/**
+ * Attach provider class for attaching to a Java virtual machine.
+ * <p/>
+ * <p> An attach provider is a concrete subclass of this class that has a
+ * zero-argument constructor and implements the abstract methods specified
+ * below. </p>
+ * <p/>
+ * <p> An attach provider implementation is typically tied to a Java virtual
+ * machine implementation, version, or even mode of operation. That is, a specific
+ * provider implementation will typically only be capable of attaching to
+ * a specific Java virtual machine implementation or version. For example, Sun's
+ * JDK implementation ships with provider implementations that can only attach to
+ * Sun's <i>HotSpot</i> virtual machine. In general, if an environment
+ * consists of Java virtual machines of different versions and from different
+ * vendors then there will be an attach provider implementation for each
+ * <i>family</i> of implementations or versions. </p>
+ * <p/>
+ * <p> An attach provider is identified by its {@link #name <i>name</i>} and
+ * {@link #type <i>type</i>}. The <i>name</i> is typically, but not required to
+ * be, a name that corresponds to the VM vendor. The Sun JDK implementation,
+ * for example, ships with attach providers that use the name <i>"sun"</i>. The
+ * <i>type</i> typically corresponds to the attach mechanism. For example, an
+ * implementation that uses the Doors inter-process communication mechanism
+ * might use the type <i>"doors"</i>. The purpose of the name and type is to
+ * identify providers in environments where there are multiple providers
+ * installed. </p>
+ * <p/>
+ * <p> AttachProvider implementations are loaded and instantiated at the first
+ * invocation of the {@link #providers() providers} method. This method
+ * attempts to load all provider implementations that are installed on the
+ * platform. </p>
+ * <p/>
+ * <p> All of the methods in this class are safe for use by multiple
+ * concurrent threads. </p>
+ *
+ * @since 1.6
+ */
+public abstract class AttachProvider
+{
+ private static final Object lock = new Object();
+ private static List<AttachProvider> providers;
+
+ /**
+ * Initializes a new instance of this class.
+ */
+ protected AttachProvider() {}
+
+ /**
+ * Return this provider's name.
+ *
+ * @return The name of this provider
+ */
+ public abstract String name();
+
+ /**
+ * Return this provider's type.
+ *
+ * @return The type of this provider
+ */
+ public abstract String type();
+
+ /**
+ * Attaches to a Java virtual machine.
+ * <p/>
+ * <p> A Java virtual machine is identified by an abstract identifier. The
+ * nature of this identifier is platform dependent but in many cases it will be the
+ * string representation of the process identifier (or pid). </p>
+ * <p/>
+ * <p> This method parses the identifier and maps the identifier to a Java
+ * virtual machine (in an implementation dependent manner). If the identifier
+ * cannot be parsed by the provider then an {@link
+ * com.sun.tools.attach.AttachNotSupportedException AttachNotSupportedException}
+ * is thrown. Once parsed this method attempts to attach to the Java virtual machine.
+ * If the provider detects that the identifier corresponds to a Java virtual machine
+ * that does not exist, or it corresponds to a Java virtual machine that does not support
+ * the attach mechanism implemented by this provider, or it detects that the
+ * Java virtual machine is a version to which this provider cannot attach, then
+ * an <code>AttachNotSupportedException</code> is thrown. </p>
+ *
+ * @param id The abstract identifier that identifies the Java virtual machine.
+ * @return VirtualMachine representing the target virtual machine.
+ * @throws SecurityException If a security manager has been installed and it denies
+ * {@link com.sun.tools.attach.AttachPermission AttachPermission}
+ * <tt>("attachVirtualMachine")</tt>, or other permission
+ * required by the implementation.
+ * @throws AttachNotSupportedException If the identifier cannot be parsed, or it corresponds to
+ * to a Java virtual machine that does not exist, or it
+ * corresponds to a Java virtual machine which this
+ * provider cannot attach.
+ * @throws IOException If some other I/O error occurs
+ * @throws NullPointerException If <code>id</code> is <code>null</code>
+ */
+ public abstract VirtualMachine attachVirtualMachine(String id)
+ throws AttachNotSupportedException, IOException;
+
+ /**
+ * Attaches to a Java virtual machine.
+ * <p/>
+ * A Java virtual machine can be described using a {@link
+ * com.sun.tools.attach.VirtualMachineDescriptor VirtualMachineDescriptor}.
+ * This method invokes the descriptor's {@link
+ * com.sun.tools.attach.VirtualMachineDescriptor#provider() provider()} method
+ * to check that it is equal to this provider. It then attempts to attach to the
+ * Java virtual machine.
+ *
+ * @param vmd The virtual machine descriptor
+ * @return VirtualMachine representing the target virtual machine.
+ * @throws SecurityException If a security manager has been installed and it denies
+ * {@link com.sun.tools.attach.AttachPermission AttachPermission}
+ * <tt>("attachVirtualMachine")</tt>, or other permission
+ * required by the implementation.
+ * @throws AttachNotSupportedException If the descriptor's {@link
+ * com.sun.tools.attach.VirtualMachineDescriptor#provider() provider()} method
+ * returns a provider that is not this provider, or it does not correspond
+ * to a Java virtual machine to which this provider can attach.
+ * @throws IOException If some other I/O error occurs
+ * @throws NullPointerException If <code>vmd</code> is <code>null</code>
+ */
+ public VirtualMachine attachVirtualMachine(VirtualMachineDescriptor vmd)
+ throws AttachNotSupportedException, IOException
+ {
+ if (vmd.provider() != this) {
+ throw new AttachNotSupportedException("provider mismatch");
+ }
+
+ return attachVirtualMachine(vmd.id());
+ }
+
+ /**
+ * Lists the Java virtual machines known to this provider.
+ * <p/>
+ * This method returns a list of {@link com.sun.tools.attach.VirtualMachineDescriptor} elements.
+ * Each <code>VirtualMachineDescriptor</code> describes a Java virtual machine
+ * to which this provider can <i>potentially</i> attach. There isn't any
+ * guarantee that invoking {@link #attachVirtualMachine(VirtualMachineDescriptor)
+ * attachVirtualMachine} on each descriptor in the list will succeed.
+ *
+ * @return The list of virtual machine descriptors which describe the
+ * Java virtual machines known to this provider (may be empty).
+ */
+ public abstract List<VirtualMachineDescriptor> listVirtualMachines();
+
+ /**
+ * Returns a list of the installed attach providers.
+ * <p/>
+ * <p> An AttachProvider is installed on the platform if:
+ * <p/>
+ * <ul>
+ * <li><p>It is installed in a JAR file that is visible to the defining
+ * class loader of the AttachProvider type (usually, but not required
+ * to be, the {@link java.lang.ClassLoader#getSystemClassLoader system
+ * class loader}).</p></li>
+ * <p/>
+ * <li><p>The JAR file contains a provider configuration named
+ * <tt>com.sun.tools.attach.spi.AttachProvider</tt> in the resource directory
+ * <tt>META-INF/services</tt>. </p></li>
+ * <p/>
+ * <li><p>The provider configuration file lists the full-qualified class
+ * name of the AttachProvider implementation. </p></li>
+ * </ul>
+ * <p/>
+ * <p> The format of the provider configuration file is one fully-qualified
+ * class name per line. Space and tab characters surrounding each class name,
+ * as well as blank lines are ignored. The comment character is
+ * <tt>'#'</tt> (<tt>0x23</tt>), and on each line all characters following
+ * the first comment character are ignored. The file must be encoded in
+ * UTF-8. </p>
+ * <p/>
+ * <p> AttachProvider implementations are loaded and instantiated
+ * (using the zero-arg constructor) at the first invocation of this method.
+ * The list returned by the first invocation of this method is the list
+ * of providers. Subsequent invocations of this method return a list of the same
+ * providers. The list is unmodifable.</p>
+ *
+ * @return A list of the installed attach providers.
+ */
+ @SuppressWarnings({"Since15"})
+ public static List<AttachProvider> providers()
+ {
+ synchronized (lock) {
+ if (providers == null) {
+ providers = new ArrayList<AttachProvider>();
+
+ ServiceLoader<AttachProvider> providerLoader =
+ ServiceLoader.load(AttachProvider.class, AttachProvider.class.getClassLoader());
+
+ for (AttachProvider aProviderLoader : providerLoader) {
+ try {
+ providers.add(aProviderLoader);
+ }
+ catch (ThreadDeath td) {
+ throw td;
+ }
+ catch (Throwable t) {
+ // Ignore errors and exceptions.
+ System.err.println(t);
+ }
+ }
+ }
+
+ return Collections.unmodifiableList(providers);
+ }
+ }
+}