Springboot @ServerEndPoint "Failed to find the root WebApplicationContext."
Springboot @ServerEndPoint "Failed to find the root WebApplicationContext."
我在使用带有 @ServerEndPoint 注释 class
的 spring 时遇到问题
我正在使用 Springboot 1.2.3,我正在尝试弄清楚如何拥有端点的单个实例
@SpringBootApplication
@EnableJpaRepositories
@EnableWebSocket
public class ApplicationServer {
public static void main(String[] args) {
SpringApplication.run(ApplicationServer.class, args);
}
}
Spring配置:
@ConditionalOnWebApplication
@Configuration
public class WebSocketConfigurator {
@Bean
public ServerEndPoint serverEndpoint() {
return new ServerEndPoint();
}
@Bean
public ServerEndpointExporter serverEndpointExporter() {
return new ServerEndpointExporter();
}
}
WebSocket 端点:
@ServerEndpoint(value = "/", decoders = MessageDecoder.class,
encoders = MessageEncoder.class, configurator = SpringConfigurator.class)
public class ServerEndPoint {
private static final Logger LOG = LoggerFactory.getLogger(ServerEndPoint.class);
public static final Set<CommunicationObserver> OBSERVERS = Sets.newConcurrentHashSet();
@OnMessage
public void onMessage(Session session, Message msg) {
LOG.debug("Received msg {} from {}", msg, session.getId());
for (CommunicationObserver o : OBSERVERS) {
o.packetReceived(session, msg);
}
}
这是基于 Spring WebSocket JSR-356 tutorial,但出现以下错误:
java.lang.IllegalStateException: Failed to find the root WebApplicationContext. Was ContextLoaderListener not used?
at org.springframework.web.socket.server.standard.SpringConfigurator.getEndpointInstance(SpringConfigurator.java:68)
at org.apache.tomcat.websocket.pojo.PojoEndpointServer.onOpen(PojoEndpointServer.java:50)
at org.apache.tomcat.websocket.server.WsHttpUpgradeHandler.init(WsHttpUpgradeHandler.java:138)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:687)
at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:223)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1558)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1515)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
我已经在嵌入式模式和外部 tomcat 8 和 jetty 9 下进行了测试(在外部模式下,我删除了 de Spring 配置文件)但是出现了同样的错误。
public class SpringEndpointConfigurator extends ServerEndpointConfig.Configurator {
private static WebApplicationContext wac;
public SpringEndpointConfigurator() {
}
public SpringEndpointConfigurator(WebApplicationContext wac) {
SpringEndpointConfigurator.wac = wac;
}
@Override
public <T> T getEndpointInstance(Class<T> endpointClass) throws InstantiationException {
T endPoint = wac.getAutowireCapableBeanFactory().getBean(endpointClass);
return (endPoint != null) ? endPoint : wac.getAutowireCapableBeanFactory().createBean(endpointClass);
}
它被创建为带有参数化构造函数的@Bean。
使用 SpringConfigurator class 我一定是错过了什么,但我不知道是什么。
感谢 Sergi Almar 和 his answer,我成功地使用了 Spring 实现而不是 javax.websocket 实现:
public class SpringWebSocketHandler extends TextWebSocketHandler {
private final Set<CommunicationObserver> observers = Sets.newConcurrentHashSet();
@Autowired
private MessageContext mc;
@Override
protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {
Message msg = mc.parse(message.getPayload());
for (CommunicationObserver o : observers) {
o.packetReceived(session, msg);
}
}
}
配置文件:
@ConditionalOnWebApplication
@Configuration
public class WebSocketConfigurator implements WebSocketConfigurer {
@Override
public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
registry.addHandler(myHandler(), "/").setAllowedOrigins("*");
}
@Bean
public SpringWebSocketHandler myHandler() {
return new SpringWebSocketHandler();
}
}
请注意,setAllowedOrigins("*") 对我来说是强制性的,因为在使用 java 客户端时,我遇到了以下错误:
org.springframework.web.util.WebUtils : Failed to parse Origin header value [localhost:8080]
另请注意,MessageContext 用于 parse/format 字符串而不是 MessageEncoder/Decoder 类(它们继承自 MessageContext)。
使用 Spring 启动时,Spring 上下文不会通过 SpringContextLoaderListener
加载,而 SpringConfigurator.class
需要
。
这就是为什么需要端点和 ServerEndpointExporter
bean 的原因。
要使示例正常工作,您唯一需要做的就是从 @ServerEndPoint
端点定义中删除 SpringConfigurator.class
。
SpringConfigurator
使用 ContextLoader
获取 spring 上下文。 Spring Boot 确实设置了 ServletContext 但它从不使用 ContextLoaderListener
来初始化 ContextLoader
以保持 spring 上下文的静态状态。您可以尝试添加 ContextLoaderListener
或作为解决方法,您可以编写自己的上下文持有者和配置器。
这是一个例子:
第一个上下文持有者和配置器:
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import javax.websocket.server.ServerEndpointConfig;
public class CustomSpringConfigurator extends ServerEndpointConfig.Configurator implements ApplicationContextAware {
/**
* Spring application context.
*/
private static volatile BeanFactory context;
@Override
public <T> T getEndpointInstance(Class<T> clazz) throws InstantiationException {
return context.getBean(clazz);
}
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
CustomSpringConfigurator.context = applicationContext;
}
}
要获取上下文,我们需要将其配置为 Bean:
@ConditionalOnWebApplication
@Configuration
public class WebSocketConfigurator {
...
@Bean
public CustomSpringConfigurator customSpringConfigurator() {
return new CustomSpringConfigurator(); // This is just to get context
}
}
然后你需要正确设置配置器:
@ServerEndpoint(value = "/", decoders = MessageDecoder.class,
encoders = MessageEncoder.class, configurator = CustomSpringConfigurator.class)
public class ServerEndPoint {
...
}
附带说明,是的,如果您删除 SpringConfigurator
,您的应用程序将启动并且您可以处理请求。但是你不能自动装配其他 bean。
我在使用带有 @ServerEndPoint 注释 class
的 spring 时遇到问题我正在使用 Springboot 1.2.3,我正在尝试弄清楚如何拥有端点的单个实例
@SpringBootApplication
@EnableJpaRepositories
@EnableWebSocket
public class ApplicationServer {
public static void main(String[] args) {
SpringApplication.run(ApplicationServer.class, args);
}
}
Spring配置:
@ConditionalOnWebApplication
@Configuration
public class WebSocketConfigurator {
@Bean
public ServerEndPoint serverEndpoint() {
return new ServerEndPoint();
}
@Bean
public ServerEndpointExporter serverEndpointExporter() {
return new ServerEndpointExporter();
}
}
WebSocket 端点:
@ServerEndpoint(value = "/", decoders = MessageDecoder.class,
encoders = MessageEncoder.class, configurator = SpringConfigurator.class)
public class ServerEndPoint {
private static final Logger LOG = LoggerFactory.getLogger(ServerEndPoint.class);
public static final Set<CommunicationObserver> OBSERVERS = Sets.newConcurrentHashSet();
@OnMessage
public void onMessage(Session session, Message msg) {
LOG.debug("Received msg {} from {}", msg, session.getId());
for (CommunicationObserver o : OBSERVERS) {
o.packetReceived(session, msg);
}
}
这是基于 Spring WebSocket JSR-356 tutorial,但出现以下错误:
java.lang.IllegalStateException: Failed to find the root WebApplicationContext. Was ContextLoaderListener not used?
at org.springframework.web.socket.server.standard.SpringConfigurator.getEndpointInstance(SpringConfigurator.java:68)
at org.apache.tomcat.websocket.pojo.PojoEndpointServer.onOpen(PojoEndpointServer.java:50)
at org.apache.tomcat.websocket.server.WsHttpUpgradeHandler.init(WsHttpUpgradeHandler.java:138)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:687)
at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:223)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1558)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1515)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
我已经在嵌入式模式和外部 tomcat 8 和 jetty 9 下进行了测试(在外部模式下,我删除了 de Spring 配置文件)但是出现了同样的错误。
public class SpringEndpointConfigurator extends ServerEndpointConfig.Configurator {
private static WebApplicationContext wac;
public SpringEndpointConfigurator() {
}
public SpringEndpointConfigurator(WebApplicationContext wac) {
SpringEndpointConfigurator.wac = wac;
}
@Override
public <T> T getEndpointInstance(Class<T> endpointClass) throws InstantiationException {
T endPoint = wac.getAutowireCapableBeanFactory().getBean(endpointClass);
return (endPoint != null) ? endPoint : wac.getAutowireCapableBeanFactory().createBean(endpointClass);
}
它被创建为带有参数化构造函数的@Bean。
使用 SpringConfigurator class 我一定是错过了什么,但我不知道是什么。
感谢 Sergi Almar 和 his answer,我成功地使用了 Spring 实现而不是 javax.websocket 实现:
public class SpringWebSocketHandler extends TextWebSocketHandler {
private final Set<CommunicationObserver> observers = Sets.newConcurrentHashSet();
@Autowired
private MessageContext mc;
@Override
protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {
Message msg = mc.parse(message.getPayload());
for (CommunicationObserver o : observers) {
o.packetReceived(session, msg);
}
}
}
配置文件:
@ConditionalOnWebApplication
@Configuration
public class WebSocketConfigurator implements WebSocketConfigurer {
@Override
public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
registry.addHandler(myHandler(), "/").setAllowedOrigins("*");
}
@Bean
public SpringWebSocketHandler myHandler() {
return new SpringWebSocketHandler();
}
}
请注意,setAllowedOrigins("*") 对我来说是强制性的,因为在使用 java 客户端时,我遇到了以下错误:
org.springframework.web.util.WebUtils : Failed to parse Origin header value [localhost:8080]
另请注意,MessageContext 用于 parse/format 字符串而不是 MessageEncoder/Decoder 类(它们继承自 MessageContext)。
使用 Spring 启动时,Spring 上下文不会通过 SpringContextLoaderListener
加载,而 SpringConfigurator.class
需要
这就是为什么需要端点和 ServerEndpointExporter
bean 的原因。
要使示例正常工作,您唯一需要做的就是从 @ServerEndPoint
端点定义中删除 SpringConfigurator.class
。
SpringConfigurator
使用 ContextLoader
获取 spring 上下文。 Spring Boot 确实设置了 ServletContext 但它从不使用 ContextLoaderListener
来初始化 ContextLoader
以保持 spring 上下文的静态状态。您可以尝试添加 ContextLoaderListener
或作为解决方法,您可以编写自己的上下文持有者和配置器。
这是一个例子:
第一个上下文持有者和配置器:
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import javax.websocket.server.ServerEndpointConfig;
public class CustomSpringConfigurator extends ServerEndpointConfig.Configurator implements ApplicationContextAware {
/**
* Spring application context.
*/
private static volatile BeanFactory context;
@Override
public <T> T getEndpointInstance(Class<T> clazz) throws InstantiationException {
return context.getBean(clazz);
}
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
CustomSpringConfigurator.context = applicationContext;
}
}
要获取上下文,我们需要将其配置为 Bean:
@ConditionalOnWebApplication
@Configuration
public class WebSocketConfigurator {
...
@Bean
public CustomSpringConfigurator customSpringConfigurator() {
return new CustomSpringConfigurator(); // This is just to get context
}
}
然后你需要正确设置配置器:
@ServerEndpoint(value = "/", decoders = MessageDecoder.class,
encoders = MessageEncoder.class, configurator = CustomSpringConfigurator.class)
public class ServerEndPoint {
...
}
附带说明,是的,如果您删除 SpringConfigurator
,您的应用程序将启动并且您可以处理请求。但是你不能自动装配其他 bean。