| /* |
| * Copyright (c) 2002, 2015, 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.io.UncheckedIOException; |
| import java.net.MalformedURLException; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.ServiceLoader; |
| import java.util.ServiceLoader.Provider; |
| import java.util.StringTokenizer; |
| import java.util.function.Predicate; |
| import java.util.stream.Stream; |
| 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 <a |
| * href="{@docRoot}/../java/util/ServiceLoader.html#developing-service-providers">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>. |
| * </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) { |
| Predicate<Provider<?>> systemProvider = |
| JMXConnectorFactory::isSystemProvider; |
| // 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. |
| JMXConnector connection = null; |
| if (loader != null) { |
| try { |
| connection = getConnectorAsService(loader, |
| providerURL, |
| envcopy, |
| systemProvider.negate()); |
| if (connection != null) return connection; |
| } catch (JMXProviderException e) { |
| throw e; |
| } catch (IOException e) { |
| exception = e; |
| } |
| } |
| connection = getConnectorAsService( |
| JMXConnectorFactory.class.getClassLoader(), |
| providerURL, |
| Collections.unmodifiableMap(envcopy), |
| systemProvider); |
| if (connection != null) return connection; |
| } |
| |
| 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; |
| } |
| |
| 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; |
| } |
| |
| /** |
| * Checks whether the given provider is our system provider for |
| * the RMI connector. |
| * If providers for additional protocols are added in the future |
| * then the name of their modules may need to be added here. |
| * System providers will be loaded only if no other provider is found. |
| * @param provider the provider to test. |
| * @return true if this provider is a default system provider. |
| */ |
| static boolean isSystemProvider(Provider<?> provider) { |
| Module providerModule = provider.type().getModule(); |
| return providerModule.isNamed() |
| && providerModule.getName().equals("java.management.rmi"); |
| } |
| |
| /** |
| * Creates a JMXConnector from the first JMXConnectorProvider service |
| * supporting the given url that can be loaded from the given loader. |
| * <p> |
| * Parses the list of JMXConnectorProvider services that can be loaded |
| * from the given loader, only retaining those that satisfy the given filter. |
| * Then for each provider, attempts to create a new JMXConnector. |
| * The first JMXConnector successfully created is returned. |
| * <p> |
| * The filter predicate is usually used to either exclude system providers |
| * or only retain system providers (see isSystemProvider(...) above). |
| * |
| * @param loader The ClassLoader to use when looking up an implementation |
| * of the service. If null, then only installed services will be |
| * considered. |
| * |
| * @param url The JMXServiceURL of the connector for which a provider is |
| * requested. |
| * |
| * @param filter A filter used to exclude or return provider |
| * implementations. Typically the filter will either exclude |
| * system services (system default implementations) or only |
| * retain those. |
| * This can allow to first look for custom implementations (e.g. |
| * deployed on the CLASSPATH with META-INF/services) and |
| * then only default to system implementations. |
| * |
| * @throws IOException if no connector could not be instantiated, and |
| * at least one provider threw an exception that wasn't a |
| * {@code MalformedURLException} or a {@code JMProviderException}. |
| * |
| * @throws JMXProviderException if a provider for the protocol in |
| * <code>url</code> was found, but couldn't create the connector |
| * some reason. |
| * |
| * @return an instance of JMXConnector if a provider was found from |
| * which one could be instantiated, {@code null} otherwise. |
| */ |
| private static JMXConnector getConnectorAsService(ClassLoader loader, |
| JMXServiceURL url, |
| Map<String, ?> map, |
| Predicate<Provider<?>> filter) |
| throws IOException { |
| |
| final ConnectorFactory<JMXConnectorProvider, JMXConnector> factory = |
| (p) -> p.newJMXConnector(url, map); |
| return getConnectorAsService(JMXConnectorProvider.class, loader, url, |
| filter, factory); |
| } |
| |
| |
| /** |
| * A factory function that can create a connector from a provider. |
| * The pair (P,C) will be either one of: |
| * a. (JMXConnectorProvider, JMXConnector) or |
| * b. (JMXConnectorServerProvider, JMXConnectorServer) |
| */ |
| @FunctionalInterface |
| static interface ConnectorFactory<P,C> { |
| public C apply(P provider) throws Exception; |
| } |
| |
| /** |
| * An instance of ProviderFinder is used to traverse a |
| * {@code Stream<Provider<P>>} and find the first implementation of P |
| * that supports creating a connector C from the given JMXServiceURL. |
| * <p> |
| * The pair (P,C) will be either one of: <br> |
| * a. (JMXConnectorProvider, JMXConnector) or <br> |
| * b. (JMXConnectorServerProvider, JMXConnectorServer) |
| * <p> |
| * The first connector successfully created while traversing the stream |
| * is stored in the ProviderFinder instance. After that, the |
| * ProviderFinder::test method, if called, will always return false, skipping |
| * the remaining providers. |
| * <p> |
| * An instance of ProviderFinder is always expected to be used in conjunction |
| * with Stream::findFirst, so that the stream traversal is stopped as soon |
| * as a matching provider is found. |
| * <p> |
| * At the end of the stream traversal, the ProviderFinder::get method can be |
| * used to obtain the connector instance (an instance of C) that was created. |
| * If no connector could be created, and an exception was encountered while |
| * traversing the stream and attempting to create the connector, then that |
| * exception will be thrown by ProviderFinder::get, wrapped, if needed, |
| * inside an IOException. |
| * <p> |
| * If any JMXProviderException is encountered while traversing the stream and |
| * attempting to create the connector, that exception will be wrapped in an |
| * UncheckedIOException and thrown immediately within the stream, thus |
| * interrupting the traversal. |
| * <p> |
| * If no matching provider was found (no provider found or attempting |
| * factory.apply always returned null or threw a MalformedURLException, |
| * indicating the provider didn't support the protocol asked for by |
| * the JMXServiceURL), then ProviderFinder::get will simply return null. |
| */ |
| private static final class ProviderFinder<P,C> implements Predicate<Provider<P>> { |
| |
| final ConnectorFactory<P,C> factory; |
| final JMXServiceURL url; |
| private IOException exception = null; |
| private C connection = null; |
| |
| ProviderFinder(ConnectorFactory<P,C> factory, JMXServiceURL url) { |
| this.factory = factory; |
| this.url = url; |
| } |
| |
| /** |
| * Returns {@code true} for the first provider {@code sp} that can |
| * be used to obtain an instance of {@code C} from the given |
| * {@code factory}. |
| * |
| * @param sp a candidate provider for instantiating {@code C}. |
| * |
| * @throws UncheckedIOException if {@code sp} throws a |
| * JMXProviderException. The JMXProviderException is set as the |
| * root cause. |
| * |
| * @return {@code true} for the first provider {@code sp} for which |
| * {@code C} could be instantiated, {@code false} otherwise. |
| */ |
| public boolean test(Provider<P> sp) { |
| if (connection == null) { |
| P provider = sp.get(); |
| try { |
| connection = factory.apply(provider); |
| return connection != null; |
| } catch (JMXProviderException e) { |
| throw new UncheckedIOException(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); |
| } |
| } |
| } |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Returns an instance of {@code C} if a provider was found from |
| * which {@code C} could be instantiated. |
| * |
| * @throws IOException if {@code C} could not be instantiated, and |
| * at least one provider threw an exception that wasn't a |
| * {@code MalformedURLException} or a {@code JMProviderException}. |
| * |
| * @return an instance of {@code C} if a provider was found from |
| * which {@code C} could be instantiated, {@code null} otherwise. |
| */ |
| C get() throws IOException { |
| if (connection != null) return connection; |
| else if (exception != null) throw exception; |
| else return null; |
| } |
| } |
| |
| /** |
| * Creates a connector from a provider loaded from the ServiceLoader. |
| * <p> |
| * The pair (P,C) will be either one of: <br> |
| * a. (JMXConnectorProvider, JMXConnector) or <br> |
| * b. (JMXConnectorServerProvider, JMXConnectorServer) |
| * |
| * @param providerClass The service type for which an implementation |
| * should be looked up from the {@code ServiceLoader}. This will |
| * be either {@code JMXConnectorProvider.class} or |
| * {@code JMXConnectorServerProvider.class} |
| * |
| * @param loader The ClassLoader to use when looking up an implementation |
| * of the service. If null, then only installed services will be |
| * considered. |
| * |
| * @param url The JMXServiceURL of the connector for which a provider is |
| * requested. |
| * |
| * @param filter A filter used to exclude or return provider |
| * implementations. Typically the filter will either exclude |
| * system services (system default implementations) or only |
| * retain those. |
| * This can allow to first look for custom implementations (e.g. |
| * deployed on the CLASSPATH with META-INF/services) and |
| * then only default to system implementations. |
| * |
| * @param factory A functional factory that can attempt to create an |
| * instance of connector {@code C} from a provider {@code P}. |
| * Typically, this is a simple wrapper over {@code |
| * JMXConnectorProvider::newJMXConnector} or {@code |
| * JMXConnectorProviderServer::newJMXConnectorServer}. |
| * |
| * @throws IOException if {@code C} could not be instantiated, and |
| * at least one provider {@code P} threw an exception that wasn't a |
| * {@code MalformedURLException} or a {@code JMProviderException}. |
| * |
| * @throws JMXProviderException if a provider {@code P} for the protocol in |
| * <code>url</code> was found, but couldn't create the connector |
| * {@code C} for some reason. |
| * |
| * @return an instance of {@code C} if a provider {@code P} was found from |
| * which one could be instantiated, {@code null} otherwise. |
| */ |
| static <P,C> C getConnectorAsService(Class<P> providerClass, |
| ClassLoader loader, |
| JMXServiceURL url, |
| Predicate<Provider<?>> filter, |
| ConnectorFactory<P,C> factory) |
| throws IOException { |
| |
| // sanity check |
| if (JMXConnectorProvider.class != providerClass |
| && JMXConnectorServerProvider.class != providerClass) { |
| // should never happen |
| throw new InternalError("Unsupported service interface: " |
| + providerClass.getName()); |
| } |
| |
| ServiceLoader<P> serviceLoader = loader == null |
| ? ServiceLoader.loadInstalled(providerClass) |
| : ServiceLoader.load(providerClass, loader); |
| Stream<Provider<P>> stream = serviceLoader.stream().filter(filter); |
| ProviderFinder<P,C> finder = new ProviderFinder<>(factory, url); |
| |
| try { |
| stream.filter(finder).findFirst(); |
| return finder.get(); |
| } catch (UncheckedIOException e) { |
| if (e.getCause() instanceof JMXProviderException) { |
| throw (JMXProviderException) e.getCause(); |
| } else { |
| throw e; |
| } |
| } |
| } |
| |
| 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 { |
| @SuppressWarnings("deprecation") |
| T result = providerClassT.newInstance(); |
| return result; |
| } 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('-', '_'); |
| } |
| } |
