我一直使用 GlassFish 4 作为我的服务器。 我正在使用以下语句打开 WebSocket 连接：
webSocket = new WebSocket(link);
地点：
link = 'ws://localhost:8080/CollabEdit/Document/file333B1CDF85-DDDC-E411-8299-F82FA8BE8622';
在服务器文件中：
@ServerEndpoint(value="/file333B1CDF85-DDDC-E411-8299-F82FA8BE8622", encoders = {MessageEncoder.class}, decoders = {MessageDecoder.class})
其实我也一直在使用URL映射，这个“file333B1CDF85-DDDC-E411-8299-F82FA8BE8622”实际上是给用户的，但在后端，控件在“main.jsp”中“ 文件。 执行过程中，产生的错误是：
WebSocket connection to 'ws://localhost:8080/CollabEdit/Document/file333B1CDF85-DDDC-E411-8299-F82FA8BE8622' failed: Error during WebSocket handshake: Unexpected response code: 200
StackTrace：
SEVERE: WebModule[/CollabEdit]Exception starting filter WebSocket filter
java.lang.InstantiationException
at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:135)
at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:5297)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:5909)
at com.sun.enterprise.web.WebModule.start(WebModule.java:691)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:1041)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:1024)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:747)
at com.sun.enterprise.web.WebContainer.loadWebModule(WebContainer.java:2278)
at com.sun.enterprise.web.WebContainer.loadWebModule(WebContainer.java:1924)
at com.sun.enterprise.web.WebApplication.start(WebApplication.java:139)
at org.glassfish.internal.data.EngineRef.start(EngineRef.java:122)
at org.glassfish.internal.data.ModuleInfo.start(ModuleInfo.java:291)
at org.glassfish.internal.data.ApplicationInfo.start(ApplicationInfo.java:352)
at com.sun.enterprise.v3.server.ApplicationLifecycle.deploy(ApplicationLifecycle.java:497)
at com.sun.enterprise.v3.server.ApplicationLifecycle.deploy(ApplicationLifecycle.java:219)
at org.glassfish.deployment.admin.DeployCommand.execute(DeployCommand.java:491)
at com.sun.enterprise.v3.admin.CommandRunnerImpl$2$1.run(CommandRunnerImpl.java:527)
at com.sun.enterprise.v3.admin.CommandRunnerImpl$2$1.run(CommandRunnerImpl.java:523)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:356)
at com.sun.enterprise.v3.admin.CommandRunnerImpl$2.execute(CommandRunnerImpl.java:522)
at com.sun.enterprise.v3.admin.CommandRunnerImpl.doCommand(CommandRunnerImpl.java:546)
at com.sun.enterprise.v3.admin.CommandRunnerImpl.doCommand(CommandRunnerImpl.java:1423)
at com.sun.enterprise.v3.admin.CommandRunnerImpl.access$1500(CommandRunnerImpl.java:108)
at com.sun.enterprise.v3.admin.CommandRunnerImpl$ExecutionContext.execute(CommandRunnerImpl.java:1762)
at com.sun.enterprise.v3.admin.CommandRunnerImpl$ExecutionContext.execute(CommandRunnerImpl.java:1674)
at com.sun.enterprise.v3.admin.AdminAdapter.doCommand(AdminAdapter.java:534)
at com.sun.enterprise.v3.admin.AdminAdapter.onMissingResource(AdminAdapter.java:224)
at org.glassfish.grizzly.http.server.StaticHttpHandler.service(StaticHttpHandler.java:297)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:246)
at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191)
at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168)
at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189)
at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114)
at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838)
at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544)
at java.lang.Thread.run(Thread.java:744)
Caused by: javax.servlet.ServletException: Web socket server initialization failed.
at org.glassfish.tyrus.servlet.TyrusServletFilter.init(TyrusServletFilter.java:135)
at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:275)
at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:131)
... 46 more
Caused by: javax.websocket.DeploymentException: Decoder for type: class com.CollabEdit.Message has not been registered.
Decoder for type: class com.CollabEdit.Message has not been registered.
at org.glassfish.tyrus.core.ErrorCollector.composeComprehensiveException(ErrorCollector.java:83)
at org.glassfish.tyrus.server.TyrusServerContainer.start(TyrusServerContainer.java:144)
at org.glassfish.tyrus.servlet.TyrusServletFilter.init(TyrusServletFilter.java:133)
... 48 more
Message.java：
package com.CollabEdit;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.StringWriter;
import javax.json.Json;
import javax.json.JsonObject;
public class Message {
private JsonObject json;
public Message(JsonObject json) {
this.json = json;
}
public JsonObject getJson() {
return json;
}
public void setJson(JsonObject json) {
this.json = json;
}
@Override
public String toString(){
StringWriter writer = new StringWriter();
Json.createWriter(writer).write(json);
return writer.toString();
}
}
MessageDecoder.java:
package com.CollabEdit;
import java.io.StringReader;
import javax.json.Json;
import javax.json.JsonException;
import javax.json.JsonObject;
import javax.websocket.DecodeException;
import javax.websocket.Decoder;
import javax.websocket.EndpointConfig;
/**
* Decodes a client-sent string into a Message class
*/
public class MessageDecoder implements Decoder.Text<Message>
{
/**
* Transform the input string into a Message
*/
@Override
public Message decode(String string) throws DecodeException {
JsonObject json = Json.createReader(new StringReader(string)).readObject();
return new Message(json);
}
/**
* Checks whether the input can be turned into a valid Message object
* in this case, if we can read it as a Json object, we can.
*/
@Override
public boolean willDecode(String string) {
try {
Json.createReader(new StringReader(string)).read();
return true;
} catch (JsonException ex) {
ex.printStackTrace();
return false;
}
}
/**
* The following two methods are placeholders as we don't need to do anything
* special for init or destroy.
*/
@Override
public void init(EndpointConfig config) {
System.out.println("init");
}
@Override
public void destroy() {
System.out.println("destroy");
}
}c
在此输入代码