Java tutorial
/* * Copyright 2012-2018 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 * * http://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.boot.web.servlet; import java.util.LinkedHashMap; import java.util.Map; import javax.servlet.Registration; import javax.servlet.ServletContext; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.core.Conventions; import org.springframework.util.Assert; import org.springframework.util.StringUtils; /** * Base class for Servlet 3.0+ {@link javax.servlet.Registration.Dynamic dynamic} based * registration beans. * * @param <D> the dynamic registration result * @author Phillip Webb * @since 2.0.0 */ public abstract class DynamicRegistrationBean<D extends Registration.Dynamic> extends RegistrationBean { private static final Log logger = LogFactory.getLog(RegistrationBean.class); private String name; private boolean asyncSupported = true; private Map<String, String> initParameters = new LinkedHashMap<>(); /** * Set the name of this registration. If not specified the bean name will be used. * @param name the name of the registration */ public void setName(String name) { Assert.hasLength(name, "Name must not be empty"); this.name = name; } /** * Sets if asynchronous operations are supported for this registration. If not * specified defaults to {@code true}. * @param asyncSupported if async is supported */ public void setAsyncSupported(boolean asyncSupported) { this.asyncSupported = asyncSupported; } /** * Returns if asynchronous operations are supported for this registration. * @return if async is supported */ public boolean isAsyncSupported() { return this.asyncSupported; } /** * Set init-parameters for this registration. Calling this method will replace any * existing init-parameters. * @param initParameters the init parameters * @see #getInitParameters * @see #addInitParameter */ public void setInitParameters(Map<String, String> initParameters) { Assert.notNull(initParameters, "InitParameters must not be null"); this.initParameters = new LinkedHashMap<>(initParameters); } /** * Returns a mutable Map of the registration init-parameters. * @return the init parameters */ public Map<String, String> getInitParameters() { return this.initParameters; } /** * Add a single init-parameter, replacing any existing parameter with the same name. * @param name the init-parameter name * @param value the init-parameter value */ public void addInitParameter(String name, String value) { Assert.notNull(name, "Name must not be null"); this.initParameters.put(name, value); } @Override protected final void register(String description, ServletContext servletContext) { D registration = addRegistration(description, servletContext); if (registration == null) { logger.info(StringUtils.capitalize(description) + " was not registered " + "(possibly already registered?)"); return; } configure(registration); } protected abstract D addRegistration(String description, ServletContext servletContext); protected void configure(D registration) { registration.setAsyncSupported(this.asyncSupported); if (!this.initParameters.isEmpty()) { registration.setInitParameters(this.initParameters); } } /** * Deduces the name for this registration. Will return user specified name or fallback * to convention based naming. * @param value the object used for convention based names * @return the deduced name */ protected final String getOrDeduceName(Object value) { return (this.name != null) ? this.name : Conventions.getVariableName(value); } }