spring SpringConfigurator 源码

spring SpringConfigurator 代码

文件路径：/spring-websocket/src/main/java/org/springframework/web/socket/server/standard/SpringConfigurator.java

/*
 * Copyright 2002-2022 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.web.socket.server.standard;

import java.util.Arrays;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

import jakarta.websocket.server.ServerEndpoint;
import jakarta.websocket.server.ServerEndpointConfig.Configurator;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.lang.Nullable;
import org.springframework.stereotype.Component;
import org.springframework.util.ClassUtils;
import org.springframework.util.ObjectUtils;
import org.springframework.web.context.ContextLoader;
import org.springframework.web.context.WebApplicationContext;

/**
 * A {@link jakarta.websocket.server.ServerEndpointConfig.Configurator} for initializing
 * {@link ServerEndpoint}-annotated classes through Spring.
 *
 * <p>
 * <pre class="code">
 * &#064;ServerEndpoint(value = "/echo", configurator = SpringConfigurator.class)
 * public class EchoEndpoint {
 *     // ...
 * }
 * </pre>
 *
 * @author Rossen Stoyanchev
 * @since 4.0
 * @see ServerEndpointExporter
 */
public class SpringConfigurator extends Configurator {

	private static final String NO_VALUE = ObjectUtils.identityToString(new Object());

	private static final Log logger = LogFactory.getLog(SpringConfigurator.class);

	private static final Map<String, Map<Class<?>, String>> cache =
			new ConcurrentHashMap<>();


	@SuppressWarnings("unchecked")
	@Override
	public <T> T getEndpointInstance(Class<T> endpointClass) throws InstantiationException {
		WebApplicationContext wac = ContextLoader.getCurrentWebApplicationContext();
		if (wac == null) {
			String message = "Failed to find the root WebApplicationContext. Was ContextLoaderListener not used?";
			logger.error(message);
			throw new IllegalStateException(message);
		}

		String beanName = ClassUtils.getShortNameAsProperty(endpointClass);
		if (wac.containsBean(beanName)) {
			T endpoint = wac.getBean(beanName, endpointClass);
			if (logger.isTraceEnabled()) {
				logger.trace("Using @ServerEndpoint singleton " + endpoint);
			}
			return endpoint;
		}

		Component ann = AnnotationUtils.findAnnotation(endpointClass, Component.class);
		if (ann != null && wac.containsBean(ann.value())) {
			T endpoint = wac.getBean(ann.value(), endpointClass);
			if (logger.isTraceEnabled()) {
				logger.trace("Using @ServerEndpoint singleton " + endpoint);
			}
			return endpoint;
		}

		beanName = getBeanNameByType(wac, endpointClass);
		if (beanName != null) {
			return (T) wac.getBean(beanName);
		}

		if (logger.isTraceEnabled()) {
			logger.trace("Creating new @ServerEndpoint instance of type " + endpointClass);
		}
		return wac.getAutowireCapableBeanFactory().createBean(endpointClass);
	}

	@Nullable
	private String getBeanNameByType(WebApplicationContext wac, Class<?> endpointClass) {
		String wacId = wac.getId();

		Map<Class<?>, String> beanNamesByType = cache.get(wacId);
		if (beanNamesByType == null) {
			beanNamesByType = new ConcurrentHashMap<>();
			cache.put(wacId, beanNamesByType);
		}

		if (!beanNamesByType.containsKey(endpointClass)) {
			String[] names = wac.getBeanNamesForType(endpointClass);
			if (names.length == 1) {
				beanNamesByType.put(endpointClass, names[0]);
			}
			else {
				beanNamesByType.put(endpointClass, NO_VALUE);
				if (names.length > 1) {
					throw new IllegalStateException("Found multiple @ServerEndpoint's of type [" +
							endpointClass.getName() + "]: bean names " + Arrays.toString(names));
				}
			}
		}

		String beanName = beanNamesByType.get(endpointClass);
		return (NO_VALUE.equals(beanName) ? null : beanName);
	}

}

相关信息

spring 源码目录

相关文章

spring AbstractStandardUpgradeStrategy 源码

spring AbstractTyrusRequestUpgradeStrategy 源码

spring GlassFishRequestUpgradeStrategy 源码

spring ServerEndpointExporter 源码

spring ServerEndpointRegistration 源码

spring ServletServerContainerFactoryBean 源码

spring TomcatRequestUpgradeStrategy 源码

spring UndertowRequestUpgradeStrategy 源码

spring WebLogicRequestUpgradeStrategy 源码

spring WebSphereRequestUpgradeStrategy 源码