org.springframework.boot.web.servlet.ServletRegistrationBean Maven / Gradle / Ivy
/*
* 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
*
* 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.boot.web.servlet;
import java.util.Arrays;
import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.Set;
import javax.servlet.MultipartConfigElement;
import javax.servlet.Servlet;
import javax.servlet.ServletContext;
import javax.servlet.ServletRegistration;
import org.springframework.util.Assert;
import org.springframework.util.ObjectUtils;
import org.springframework.util.StringUtils;
/**
* A {@link ServletContextInitializer} to register {@link Servlet}s in a Servlet 3.0+
* container. Similar to the {@link ServletContext#addServlet(String, Servlet)
* registration} features provided by {@link ServletContext} but with a Spring Bean
* friendly design.
*
* The {@link #setServlet(Servlet) servlet} must be specified before calling
* {@link #onStartup}. URL mapping can be configured used {@link #setUrlMappings} or
* omitted when mapping to '/*' (unless
* {@link #ServletRegistrationBean(Servlet, boolean, String...) alwaysMapUrl} is set to
* {@code false}). The servlet name will be deduced if not specified.
*
* @param the type of the {@link Servlet} to register
* @author Phillip Webb
* @since 1.4.0
* @see ServletContextInitializer
* @see ServletContext#addServlet(String, Servlet)
*/
public class ServletRegistrationBean
extends DynamicRegistrationBean {
private static final String[] DEFAULT_MAPPINGS = { "/*" };
private T servlet;
private Set urlMappings = new LinkedHashSet<>();
private boolean alwaysMapUrl = true;
private int loadOnStartup = -1;
private MultipartConfigElement multipartConfig;
/**
* Create a new {@link ServletRegistrationBean} instance.
*/
public ServletRegistrationBean() {
}
/**
* Create a new {@link ServletRegistrationBean} instance with the specified
* {@link Servlet} and URL mappings.
* @param servlet the servlet being mapped
* @param urlMappings the URLs being mapped
*/
public ServletRegistrationBean(T servlet, String... urlMappings) {
this(servlet, true, urlMappings);
}
/**
* Create a new {@link ServletRegistrationBean} instance with the specified
* {@link Servlet} and URL mappings.
* @param servlet the servlet being mapped
* @param alwaysMapUrl if omitted URL mappings should be replaced with '/*'
* @param urlMappings the URLs being mapped
*/
public ServletRegistrationBean(T servlet, boolean alwaysMapUrl,
String... urlMappings) {
Assert.notNull(servlet, "Servlet must not be null");
Assert.notNull(urlMappings, "UrlMappings must not be null");
this.servlet = servlet;
this.alwaysMapUrl = alwaysMapUrl;
this.urlMappings.addAll(Arrays.asList(urlMappings));
}
/**
* Sets the servlet to be registered.
* @param servlet the servlet
*/
public void setServlet(T servlet) {
Assert.notNull(servlet, "Servlet must not be null");
this.servlet = servlet;
}
/**
* Return the servlet being registered.
* @return the servlet
*/
public T getServlet() {
return this.servlet;
}
/**
* Set the URL mappings for the servlet. If not specified the mapping will default to
* '/'. This will replace any previously specified mappings.
* @param urlMappings the mappings to set
* @see #addUrlMappings(String...)
*/
public void setUrlMappings(Collection urlMappings) {
Assert.notNull(urlMappings, "UrlMappings must not be null");
this.urlMappings = new LinkedHashSet<>(urlMappings);
}
/**
* Return a mutable collection of the URL mappings, as defined in the Servlet
* specification, for the servlet.
* @return the urlMappings
*/
public Collection getUrlMappings() {
return this.urlMappings;
}
/**
* Add URL mappings, as defined in the Servlet specification, for the servlet.
* @param urlMappings the mappings to add
* @see #setUrlMappings(Collection)
*/
public void addUrlMappings(String... urlMappings) {
Assert.notNull(urlMappings, "UrlMappings must not be null");
this.urlMappings.addAll(Arrays.asList(urlMappings));
}
/**
* Sets the {@code loadOnStartup} priority. See
* {@link ServletRegistration.Dynamic#setLoadOnStartup} for details.
* @param loadOnStartup if load on startup is enabled
*/
public void setLoadOnStartup(int loadOnStartup) {
this.loadOnStartup = loadOnStartup;
}
/**
* Set the {@link MultipartConfigElement multi-part configuration}.
* @param multipartConfig the multi-part configuration to set or {@code null}
*/
public void setMultipartConfig(MultipartConfigElement multipartConfig) {
this.multipartConfig = multipartConfig;
}
/**
* Returns the {@link MultipartConfigElement multi-part configuration} to be applied
* or {@code null}.
* @return the multipart config
*/
public MultipartConfigElement getMultipartConfig() {
return this.multipartConfig;
}
@Override
protected String getDescription() {
Assert.notNull(this.servlet, "Servlet must not be null");
return "servlet " + getServletName();
}
@Override
protected ServletRegistration.Dynamic addRegistration(String description,
ServletContext servletContext) {
String name = getServletName();
return servletContext.addServlet(name, this.servlet);
}
/**
* Configure registration settings. Subclasses can override this method to perform
* additional configuration if required.
* @param registration the registration
*/
@Override
protected void configure(ServletRegistration.Dynamic registration) {
super.configure(registration);
String[] urlMapping = StringUtils.toStringArray(this.urlMappings);
if (urlMapping.length == 0 && this.alwaysMapUrl) {
urlMapping = DEFAULT_MAPPINGS;
}
if (!ObjectUtils.isEmpty(urlMapping)) {
registration.addMapping(urlMapping);
}
registration.setLoadOnStartup(this.loadOnStartup);
if (this.multipartConfig != null) {
registration.setMultipartConfig(this.multipartConfig);
}
}
/**
* Returns the servlet name that will be registered.
* @return the servlet name
*/
public String getServletName() {
return getOrDeduceName(this.servlet);
}
@Override
public String toString() {
return getServletName() + " urls=" + getUrlMappings();
}
}