jdk/src/java.management/share/classes/javax/management/remote/JMXConnectorFactory.java
changeset 25859 3317bb8137f4
parent 24368 2b4801b94265
child 32639 339de1317e84
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/java.management/share/classes/javax/management/remote/JMXConnectorFactory.java	Sun Aug 17 15:54:13 2014 +0100
@@ -0,0 +1,574 @@
+/*
+ * Copyright (c) 2002, 2014, Oracle and/or its affiliates. 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package javax.management.remote;
+
+import com.sun.jmx.mbeanserver.Util;
+import java.io.IOException;
+import java.net.MalformedURLException;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Iterator;
+import java.util.ServiceLoader;
+import java.util.StringTokenizer;
+import java.security.AccessController;
+import java.security.PrivilegedAction;
+
+import com.sun.jmx.remote.util.ClassLogger;
+import com.sun.jmx.remote.util.EnvHelp;
+import sun.reflect.misc.ReflectUtil;
+
+
+/**
+ * <p>Factory to create JMX API connector clients.  There
+ * are no instances of this class.</p>
+ *
+ * <p>Connections are usually made using the {@link
+ * #connect(JMXServiceURL) connect} method of this class.  More
+ * advanced applications can separate the creation of the connector
+ * client, using {@link #newJMXConnector(JMXServiceURL, Map)
+ * newJMXConnector} and the establishment of the connection itself, using
+ * {@link JMXConnector#connect(Map)}.</p>
+ *
+ * <p>Each client is created by an instance of {@link
+ * JMXConnectorProvider}.  This instance is found as follows.  Suppose
+ * the given {@link JMXServiceURL} looks like
+ * <code>"service:jmx:<em>protocol</em>:<em>remainder</em>"</code>.
+ * Then the factory will attempt to find the appropriate {@link
+ * JMXConnectorProvider} for <code><em>protocol</em></code>.  Each
+ * occurrence of the character <code>+</code> or <code>-</code> in
+ * <code><em>protocol</em></code> is replaced by <code>.</code> or
+ * <code>_</code>, respectively.</p>
+ *
+ * <p>A <em>provider package list</em> is searched for as follows:</p>
+ *
+ * <ol>
+ *
+ * <li>If the <code>environment</code> parameter to {@link
+ * #newJMXConnector(JMXServiceURL, Map) newJMXConnector} contains the
+ * key <code>jmx.remote.protocol.provider.pkgs</code> then the
+ * associated value is the provider package list.
+ *
+ * <li>Otherwise, if the system property
+ * <code>jmx.remote.protocol.provider.pkgs</code> exists, then its value
+ * is the provider package list.
+ *
+ * <li>Otherwise, there is no provider package list.
+ *
+ * </ol>
+ *
+ * <p>The provider package list is a string that is interpreted as a
+ * list of non-empty Java package names separated by vertical bars
+ * (<code>|</code>).  If the string is empty, then so is the provider
+ * package list.  If the provider package list is not a String, or if
+ * it contains an element that is an empty string, a {@link
+ * JMXProviderException} is thrown.</p>
+ *
+ * <p>If the provider package list exists and is not empty, then for
+ * each element <code><em>pkg</em></code> of the list, the factory
+ * will attempt to load the class
+ *
+ * <blockquote>
+ * <code><em>pkg</em>.<em>protocol</em>.ClientProvider</code>
+ * </blockquote>
+
+ * <p>If the <code>environment</code> parameter to {@link
+ * #newJMXConnector(JMXServiceURL, Map) newJMXConnector} contains the
+ * key <code>jmx.remote.protocol.provider.class.loader</code> then the
+ * associated value is the class loader to use to load the provider.
+ * If the associated value is not an instance of {@link
+ * java.lang.ClassLoader}, an {@link
+ * java.lang.IllegalArgumentException} is thrown.</p>
+ *
+ * <p>If the <code>jmx.remote.protocol.provider.class.loader</code>
+ * key is not present in the <code>environment</code> parameter, the
+ * calling thread's context class loader is used.</p>
+ *
+ * <p>If the attempt to load this class produces a {@link
+ * ClassNotFoundException}, the search for a handler continues with
+ * the next element of the list.</p>
+ *
+ * <p>Otherwise, a problem with the provider found is signalled by a
+ * {@link JMXProviderException} whose {@link
+ * JMXProviderException#getCause() <em>cause</em>} indicates the underlying
+ * exception, as follows:</p>
+ *
+ * <ul>
+ *
+ * <li>if the attempt to load the class produces an exception other
+ * than <code>ClassNotFoundException</code>, that is the
+ * <em>cause</em>;
+ *
+ * <li>if {@link Class#newInstance()} for the class produces an
+ * exception, that is the <em>cause</em>.
+ *
+ * </ul>
+ *
+ * <p>If no provider is found by the above steps, including the
+ * default case where there is no provider package list, then the
+ * implementation will use its own provider for
+ * <code><em>protocol</em></code>, or it will throw a
+ * <code>MalformedURLException</code> if there is none.  An
+ * implementation may choose to find providers by other means.  For
+ * example, it may support the <a
+ * href="{@docRoot}/../technotes/guides/jar/jar.html#Service%20Provider">
+ * JAR conventions for service providers</a>, where the service
+ * interface is <code>JMXConnectorProvider</code>.</p>
+ *
+ * <p>Every implementation must support the RMI connector protocol with
+ * the default RMI transport, specified with string <code>rmi</code>.
+ * An implementation may optionally support the RMI connector protocol
+ * with the RMI/IIOP transport, specified with the string
+ * <code>iiop</code>.</p>
+ *
+ * <p>Once a provider is found, the result of the
+ * <code>newJMXConnector</code> method is the result of calling {@link
+ * JMXConnectorProvider#newJMXConnector(JMXServiceURL,Map) newJMXConnector}
+ * on the provider.</p>
+ *
+ * <p>The <code>Map</code> parameter passed to the
+ * <code>JMXConnectorProvider</code> is a new read-only
+ * <code>Map</code> that contains all the entries that were in the
+ * <code>environment</code> parameter to {@link
+ * #newJMXConnector(JMXServiceURL,Map)
+ * JMXConnectorFactory.newJMXConnector}, if there was one.
+ * Additionally, if the
+ * <code>jmx.remote.protocol.provider.class.loader</code> key is not
+ * present in the <code>environment</code> parameter, it is added to
+ * the new read-only <code>Map</code>.  The associated value is the
+ * calling thread's context class loader.</p>
+ *
+ * @since 1.5
+ */
+public class JMXConnectorFactory {
+
+    /**
+     * <p>Name of the attribute that specifies the default class
+     * loader. This class loader is used to deserialize return values and
+     * exceptions from remote <code>MBeanServerConnection</code>
+     * calls.  The value associated with this attribute is an instance
+     * of {@link ClassLoader}.</p>
+     */
+    public static final String DEFAULT_CLASS_LOADER =
+        "jmx.remote.default.class.loader";
+
+    /**
+     * <p>Name of the attribute that specifies the provider packages
+     * that are consulted when looking for the handler for a protocol.
+     * The value associated with this attribute is a string with
+     * package names separated by vertical bars (<code>|</code>).</p>
+     */
+    public static final String PROTOCOL_PROVIDER_PACKAGES =
+        "jmx.remote.protocol.provider.pkgs";
+
+    /**
+     * <p>Name of the attribute that specifies the class
+     * loader for loading protocol providers.
+     * The value associated with this attribute is an instance
+     * of {@link ClassLoader}.</p>
+     */
+    public static final String PROTOCOL_PROVIDER_CLASS_LOADER =
+        "jmx.remote.protocol.provider.class.loader";
+
+    private static final String PROTOCOL_PROVIDER_DEFAULT_PACKAGE =
+        "com.sun.jmx.remote.protocol";
+
+    private static final ClassLogger logger =
+        new ClassLogger("javax.management.remote.misc", "JMXConnectorFactory");
+
+    /** There are no instances of this class.  */
+    private JMXConnectorFactory() {
+    }
+
+    /**
+     * <p>Creates a connection to the connector server at the given
+     * address.</p>
+     *
+     * <p>This method is equivalent to {@link
+     * #connect(JMXServiceURL,Map) connect(serviceURL, null)}.</p>
+     *
+     * @param serviceURL the address of the connector server to
+     * connect to.
+     *
+     * @return a <code>JMXConnector</code> whose {@link
+     * JMXConnector#connect connect} method has been called.
+     *
+     * @exception NullPointerException if <code>serviceURL</code> is null.
+     *
+     * @exception IOException if the connector client or the
+     * connection cannot be made because of a communication problem.
+     *
+     * @exception SecurityException if the connection cannot be made
+     * for security reasons.
+     */
+    public static JMXConnector connect(JMXServiceURL serviceURL)
+            throws IOException {
+        return connect(serviceURL, null);
+    }
+
+    /**
+     * <p>Creates a connection to the connector server at the given
+     * address.</p>
+     *
+     * <p>This method is equivalent to:</p>
+     *
+     * <pre>
+     * JMXConnector conn = JMXConnectorFactory.newJMXConnector(serviceURL,
+     *                                                         environment);
+     * conn.connect(environment);
+     * </pre>
+     *
+     * @param serviceURL the address of the connector server to connect to.
+     *
+     * @param environment a set of attributes to determine how the
+     * connection is made.  This parameter can be null.  Keys in this
+     * map must be Strings.  The appropriate type of each associated
+     * value depends on the attribute.  The contents of
+     * <code>environment</code> are not changed by this call.
+     *
+     * @return a <code>JMXConnector</code> representing the newly-made
+     * connection.  Each successful call to this method produces a
+     * different object.
+     *
+     * @exception NullPointerException if <code>serviceURL</code> is null.
+     *
+     * @exception IOException if the connector client or the
+     * connection cannot be made because of a communication problem.
+     *
+     * @exception SecurityException if the connection cannot be made
+     * for security reasons.
+     */
+    public static JMXConnector connect(JMXServiceURL serviceURL,
+                                       Map<String,?> environment)
+            throws IOException {
+        if (serviceURL == null)
+            throw new NullPointerException("Null JMXServiceURL");
+        JMXConnector conn = newJMXConnector(serviceURL, environment);
+        conn.connect(environment);
+        return conn;
+    }
+
+    private static <K,V> Map<K,V> newHashMap() {
+        return new HashMap<K,V>();
+    }
+
+    private static <K> Map<K,Object> newHashMap(Map<K,?> map) {
+        return new HashMap<K,Object>(map);
+    }
+
+    /**
+     * <p>Creates a connector client for the connector server at the
+     * given address.  The resultant client is not connected until its
+     * {@link JMXConnector#connect(Map) connect} method is called.</p>
+     *
+     * @param serviceURL the address of the connector server to connect to.
+     *
+     * @param environment a set of attributes to determine how the
+     * connection is made.  This parameter can be null.  Keys in this
+     * map must be Strings.  The appropriate type of each associated
+     * value depends on the attribute.  The contents of
+     * <code>environment</code> are not changed by this call.
+     *
+     * @return a <code>JMXConnector</code> representing the new
+     * connector client.  Each successful call to this method produces
+     * a different object.
+     *
+     * @exception NullPointerException if <code>serviceURL</code> is null.
+     *
+     * @exception IOException if the connector client cannot be made
+     * because of a communication problem.
+     *
+     * @exception MalformedURLException if there is no provider for the
+     * protocol in <code>serviceURL</code>.
+     *
+     * @exception JMXProviderException if there is a provider for the
+     * protocol in <code>serviceURL</code> but it cannot be used for
+     * some reason.
+     */
+    public static JMXConnector newJMXConnector(JMXServiceURL serviceURL,
+                                               Map<String,?> environment)
+            throws IOException {
+
+        final Map<String,Object> envcopy;
+        if (environment == null)
+            envcopy = newHashMap();
+        else {
+            EnvHelp.checkAttributes(environment);
+            envcopy = newHashMap(environment);
+        }
+
+        final ClassLoader loader = resolveClassLoader(envcopy);
+        final Class<JMXConnectorProvider> targetInterface =
+                JMXConnectorProvider.class;
+        final String protocol = serviceURL.getProtocol();
+        final String providerClassName = "ClientProvider";
+        final JMXServiceURL providerURL = serviceURL;
+
+        JMXConnectorProvider provider = getProvider(providerURL, envcopy,
+                                               providerClassName,
+                                               targetInterface,
+                                               loader);
+
+        IOException exception = null;
+        if (provider == null) {
+            // Loader is null when context class loader is set to null
+            // and no loader has been provided in map.
+            // com.sun.jmx.remote.util.Service class extracted from j2se
+            // provider search algorithm doesn't handle well null classloader.
+            if (loader != null) {
+                try {
+                    JMXConnector connection =
+                        getConnectorAsService(loader, providerURL, envcopy);
+                    if (connection != null)
+                        return connection;
+                } catch (JMXProviderException e) {
+                    throw e;
+                } catch (IOException e) {
+                    exception = e;
+                }
+            }
+            provider = getProvider(protocol, PROTOCOL_PROVIDER_DEFAULT_PACKAGE,
+                            JMXConnectorFactory.class.getClassLoader(),
+                            providerClassName, targetInterface);
+        }
+
+        if (provider == null) {
+            MalformedURLException e =
+                new MalformedURLException("Unsupported protocol: " + protocol);
+            if (exception == null) {
+                throw e;
+            } else {
+                throw EnvHelp.initCause(e, exception);
+            }
+        }
+
+        final Map<String,Object> fixedenv =
+                Collections.unmodifiableMap(envcopy);
+
+        return provider.newJMXConnector(serviceURL, fixedenv);
+    }
+
+    private static String resolvePkgs(Map<String, ?> env)
+            throws JMXProviderException {
+
+        Object pkgsObject = null;
+
+        if (env != null)
+            pkgsObject = env.get(PROTOCOL_PROVIDER_PACKAGES);
+
+        if (pkgsObject == null)
+            pkgsObject =
+                AccessController.doPrivileged(new PrivilegedAction<String>() {
+                    public String run() {
+                        return System.getProperty(PROTOCOL_PROVIDER_PACKAGES);
+                    }
+                });
+
+        if (pkgsObject == null)
+            return null;
+
+        if (!(pkgsObject instanceof String)) {
+            final String msg = "Value of " + PROTOCOL_PROVIDER_PACKAGES +
+                " parameter is not a String: " +
+                pkgsObject.getClass().getName();
+            throw new JMXProviderException(msg);
+        }
+
+        final String pkgs = (String) pkgsObject;
+        if (pkgs.trim().equals(""))
+            return null;
+
+        // pkgs may not contain an empty element
+        if (pkgs.startsWith("|") || pkgs.endsWith("|") ||
+            pkgs.indexOf("||") >= 0) {
+            final String msg = "Value of " + PROTOCOL_PROVIDER_PACKAGES +
+                " contains an empty element: " + pkgs;
+            throw new JMXProviderException(msg);
+        }
+
+        return pkgs;
+    }
+
+    static <T> T getProvider(JMXServiceURL serviceURL,
+                             final Map<String, Object> environment,
+                             String providerClassName,
+                             Class<T> targetInterface,
+                             final ClassLoader loader)
+            throws IOException {
+
+        final String protocol = serviceURL.getProtocol();
+
+        final String pkgs = resolvePkgs(environment);
+
+        T instance = null;
+
+        if (pkgs != null) {
+            instance =
+                getProvider(protocol, pkgs, loader, providerClassName,
+                            targetInterface);
+
+            if (instance != null) {
+                boolean needsWrap = (loader != instance.getClass().getClassLoader());
+                environment.put(PROTOCOL_PROVIDER_CLASS_LOADER, needsWrap ? wrap(loader) : loader);
+            }
+        }
+
+        return instance;
+    }
+
+    static <T> Iterator<T> getProviderIterator(final Class<T> providerClass,
+                                               final ClassLoader loader) {
+       ServiceLoader<T> serviceLoader =
+                ServiceLoader.load(providerClass, loader);
+       return serviceLoader.iterator();
+    }
+
+    private static ClassLoader wrap(final ClassLoader parent) {
+        return parent != null ? AccessController.doPrivileged(new PrivilegedAction<ClassLoader>() {
+            @Override
+            public ClassLoader run() {
+                return new ClassLoader(parent) {
+                    @Override
+                    protected Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundException {
+                        ReflectUtil.checkPackageAccess(name);
+                        return super.loadClass(name, resolve);
+                    }
+                };
+            }
+        }) : null;
+    }
+
+    private static JMXConnector getConnectorAsService(ClassLoader loader,
+                                                      JMXServiceURL url,
+                                                      Map<String, ?> map)
+        throws IOException {
+
+        Iterator<JMXConnectorProvider> providers =
+                getProviderIterator(JMXConnectorProvider.class, loader);
+        JMXConnector connection;
+        IOException exception = null;
+        while (providers.hasNext()) {
+            JMXConnectorProvider provider = providers.next();
+            try {
+                connection = provider.newJMXConnector(url, map);
+                return connection;
+            } catch (JMXProviderException e) {
+                throw e;
+            } catch (Exception e) {
+                if (logger.traceOn())
+                    logger.trace("getConnectorAsService",
+                                 "URL[" + url +
+                                 "] Service provider exception: " + e);
+                if (!(e instanceof MalformedURLException)) {
+                    if (exception == null) {
+                        if (e instanceof IOException) {
+                            exception = (IOException) e;
+                        } else {
+                            exception = EnvHelp.initCause(
+                                new IOException(e.getMessage()), e);
+                        }
+                    }
+                }
+                continue;
+            }
+        }
+        if (exception == null)
+            return null;
+        else
+            throw exception;
+    }
+
+    static <T> T getProvider(String protocol,
+                              String pkgs,
+                              ClassLoader loader,
+                              String providerClassName,
+                              Class<T> targetInterface)
+            throws IOException {
+
+        StringTokenizer tokenizer = new StringTokenizer(pkgs, "|");
+
+        while (tokenizer.hasMoreTokens()) {
+            String pkg = tokenizer.nextToken();
+            String className = (pkg + "." + protocol2package(protocol) +
+                                "." + providerClassName);
+            Class<?> providerClass;
+            try {
+                providerClass = Class.forName(className, true, loader);
+            } catch (ClassNotFoundException e) {
+                //Add trace.
+                continue;
+            }
+
+            if (!targetInterface.isAssignableFrom(providerClass)) {
+                final String msg =
+                    "Provider class does not implement " +
+                    targetInterface.getName() + ": " +
+                    providerClass.getName();
+                throw new JMXProviderException(msg);
+            }
+
+            // We have just proved that this cast is correct
+            Class<? extends T> providerClassT = Util.cast(providerClass);
+            try {
+                return providerClassT.newInstance();
+            } catch (Exception e) {
+                final String msg =
+                    "Exception when instantiating provider [" + className +
+                    "]";
+                throw new JMXProviderException(msg, e);
+            }
+        }
+
+        return null;
+    }
+
+    static ClassLoader resolveClassLoader(Map<String, ?> environment) {
+        ClassLoader loader = null;
+
+        if (environment != null) {
+            try {
+                loader = (ClassLoader)
+                    environment.get(PROTOCOL_PROVIDER_CLASS_LOADER);
+            } catch (ClassCastException e) {
+                final String msg =
+                    "The ClassLoader supplied in the environment map using " +
+                    "the " + PROTOCOL_PROVIDER_CLASS_LOADER +
+                    " attribute is not an instance of java.lang.ClassLoader";
+                throw new IllegalArgumentException(msg);
+            }
+        }
+
+        if (loader == null) {
+            loader = Thread.currentThread().getContextClassLoader();
+        }
+
+        return loader;
+    }
+
+    private static String protocol2package(String protocol) {
+        return protocol.replace('+', '.').replace('-', '_');
+    }
+}