Java tutorial
/* * Copyright 2002-2019 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.mock.jndi; import java.util.Hashtable; import javax.naming.Context; import javax.naming.NamingException; import javax.naming.spi.InitialContextFactory; import javax.naming.spi.InitialContextFactoryBuilder; import javax.naming.spi.NamingManager; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.lang.Nullable; import org.springframework.util.Assert; import org.springframework.util.ClassUtils; import org.springframework.util.ReflectionUtils; /** * Simple implementation of a JNDI naming context builder. * * <p>Mainly targeted at test environments, where each test case can * configure JNDI appropriately, so that {@code new InitialContext()} * will expose the required objects. Also usable for standalone applications, * e.g. for binding a JDBC DataSource to a well-known JNDI location, to be * able to use traditional Java EE data access code outside of a Java EE * container. * * <p>There are various choices for DataSource implementations: * <ul> * <li>{@code SingleConnectionDataSource} (using the same Connection for all getConnection calls) * <li>{@code DriverManagerDataSource} (creating a new Connection on each getConnection call) * <li>Apache's Commons DBCP offers {@code org.apache.commons.dbcp.BasicDataSource} (a real pool) * </ul> * * <p>Typical usage in bootstrap code: * * <pre class="code"> * SimpleNamingContextBuilder builder = new SimpleNamingContextBuilder(); * DataSource ds = new DriverManagerDataSource(...); * builder.bind("java:comp/env/jdbc/myds", ds); * builder.activate();</pre> * * Note that it's impossible to activate multiple builders within the same JVM, * due to JNDI restrictions. Thus to configure a fresh builder repeatedly, use * the following code to get a reference to either an already activated builder * or a newly activated one: * * <pre class="code"> * SimpleNamingContextBuilder builder = SimpleNamingContextBuilder.emptyActivatedContextBuilder(); * DataSource ds = new DriverManagerDataSource(...); * builder.bind("java:comp/env/jdbc/myds", ds);</pre> * * Note that you <i>should not</i> call {@code activate()} on a builder from * this factory method, as there will already be an activated one in any case. * * <p>An instance of this class is only necessary at setup time. * An application does not need to keep a reference to it after activation. * * @author Juergen Hoeller * @author Rod Johnson * @see #emptyActivatedContextBuilder() * @see #bind(String, Object) * @see #activate() * @see SimpleNamingContext * @see org.springframework.jdbc.datasource.SingleConnectionDataSource * @see org.springframework.jdbc.datasource.DriverManagerDataSource * @deprecated Deprecated as of Spring Framework 5.2 in favor of complete solutions from * third parties such as <a href="https://github.com/h-thurow/Simple-JNDI">Simple-JNDI</a> */ @Deprecated public class SimpleNamingContextBuilder implements InitialContextFactoryBuilder { /** An instance of this class bound to JNDI. */ @Nullable private static volatile SimpleNamingContextBuilder activated; private static boolean initialized = false; private static final Object initializationLock = new Object(); /** * Checks if a SimpleNamingContextBuilder is active. * @return the current SimpleNamingContextBuilder instance, * or {@code null} if none */ @Nullable public static SimpleNamingContextBuilder getCurrentContextBuilder() { return activated; } /** * If no SimpleNamingContextBuilder is already configuring JNDI, * create and activate one. Otherwise take the existing activated * SimpleNamingContextBuilder, clear it and return it. * <p>This is mainly intended for test suites that want to * reinitialize JNDI bindings from scratch repeatedly. * @return an empty SimpleNamingContextBuilder that can be used * to control JNDI bindings */ public static SimpleNamingContextBuilder emptyActivatedContextBuilder() throws NamingException { SimpleNamingContextBuilder builder = activated; if (builder != null) { // Clear already activated context builder. builder.clear(); } else { // Create and activate new context builder. builder = new SimpleNamingContextBuilder(); // The activate() call will cause an assignment to the activated variable. builder.activate(); } return builder; } private final Log logger = LogFactory.getLog(getClass()); private final Hashtable<String, Object> boundObjects = new Hashtable<>(); /** * Register the context builder by registering it with the JNDI NamingManager. * Note that once this has been done, {@code new InitialContext()} will always * return a context from this factory. Use the {@code emptyActivatedContextBuilder()} * static method to get an empty context (for example, in test methods). * @throws IllegalStateException if there's already a naming context builder * registered with the JNDI NamingManager */ public void activate() throws IllegalStateException, NamingException { logger.info("Activating simple JNDI environment"); synchronized (initializationLock) { if (!initialized) { Assert.state(!NamingManager.hasInitialContextFactoryBuilder(), "Cannot activate SimpleNamingContextBuilder: there is already a JNDI provider registered. " + "Note that JNDI is a JVM-wide service, shared at the JVM system class loader level, " + "with no reset option. As a consequence, a JNDI provider must only be registered once per JVM."); NamingManager.setInitialContextFactoryBuilder(this); initialized = true; } } activated = this; } /** * Temporarily deactivate this context builder. It will remain registered with * the JNDI NamingManager but will delegate to the standard JNDI InitialContextFactory * (if configured) instead of exposing its own bound objects. * <p>Call {@code activate()} again in order to expose this context builder's own * bound objects again. Such activate/deactivate sequences can be applied any number * of times (e.g. within a larger integration test suite running in the same VM). * @see #activate() */ public void deactivate() { logger.info("Deactivating simple JNDI environment"); activated = null; } /** * Clear all bindings in this context builder, while keeping it active. */ public void clear() { this.boundObjects.clear(); } /** * Bind the given object under the given name, for all naming contexts * that this context builder will generate. * @param name the JNDI name of the object (e.g. "java:comp/env/jdbc/myds") * @param obj the object to bind (e.g. a DataSource implementation) */ public void bind(String name, Object obj) { if (logger.isInfoEnabled()) { logger.info("Static JNDI binding: [" + name + "] = [" + obj + "]"); } this.boundObjects.put(name, obj); } /** * Simple InitialContextFactoryBuilder implementation, * creating a new SimpleNamingContext instance. * @see SimpleNamingContext */ @Override @SuppressWarnings("unchecked") public InitialContextFactory createInitialContextFactory(@Nullable Hashtable<?, ?> environment) { if (activated == null && environment != null) { Object icf = environment.get(Context.INITIAL_CONTEXT_FACTORY); if (icf != null) { Class<?> icfClass; if (icf instanceof Class) { icfClass = (Class<?>) icf; } else if (icf instanceof String) { icfClass = ClassUtils.resolveClassName((String) icf, getClass().getClassLoader()); } else { throw new IllegalArgumentException("Invalid value type for environment key [" + Context.INITIAL_CONTEXT_FACTORY + "]: " + icf.getClass().getName()); } if (!InitialContextFactory.class.isAssignableFrom(icfClass)) { throw new IllegalArgumentException("Specified class does not implement [" + InitialContextFactory.class.getName() + "]: " + icf); } try { return (InitialContextFactory) ReflectionUtils.accessibleConstructor(icfClass).newInstance(); } catch (Throwable ex) { throw new IllegalStateException("Unable to instantiate specified InitialContextFactory: " + icf, ex); } } } // Default case... return env -> new SimpleNamingContext("", this.boundObjects, (Hashtable<String, Object>) env); } }