[CAMEL-9057] Camel Example Servlet REST generates java.lang.NoClassDefFoundError: scala/xml/PrettyPrinter

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.16.0
• Component/s: examples
• Estimated Complexity: Unknown
• Assignee: Moulliard Charles
• Reporter: Moulliard Charles
• Created: 05/Aug/15 15:45
• Updated: 05/Aug/15 16:29
• Resolved: 05/Aug/15 16:20

Description

After starting jetty:run maven goal and accessing the apiDoc of Swagger (http://localhost:8080/camel-example-servlet-rest-tomcat/api-docs/myCamel), the following error is reported

2015-08-05 17:42:18.053:INFO:oejs.Server:main: Started @18962ms
[INFO] Started Jetty Server
2015-08-05 17:42:26.619:WARN:oejs.ServletHandler:qtp1891031939-25: Error for /camel-example-servlet-rest-tomcat/api-docs/myCamel
java.lang.NoClassDefFoundError: scala/xml/PrettyPrinter
        at com.wordnik.swagger.core.util.JsonSerializer$.<init>(JsonSerializer.scala:31)
        at com.wordnik.swagger.core.util.JsonSerializer$.<clinit>(JsonSerializer.scala)
        at org.apache.camel.component.swagger.RestSwaggerApiDeclarationServlet.renderResourceListing(RestSwaggerApiDeclarationServlet.scala:225)
        at org.apache.camel.component.swagger.RestSwaggerApiDeclarationServlet.doGet(RestSwaggerApiDeclarationServlet.scala:111)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
        at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:808)
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1669)
        at org.apache.camel.component.swagger.RestSwaggerCorsFilter.doFilter(RestSwaggerCorsFilter.scala:44)
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)
        at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:585)
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
        at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:577)
        at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)
        at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127)
        at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
        at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
        at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061)
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
        at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:215)
        at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:110)
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
        at org.eclipse.jetty.server.Server.handle(Server.java:497)
        at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:310)
        at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:257)
        at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540)
        at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635)
        at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555)
        at java.lang.Thread.run(Thread.java:745)
Caused by: 
java.lang.ClassNotFoundException: scala.xml.PrettyPrinter
        at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:50)
        at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:259)
        at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:235)
        at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:227)
        at org.eclipse.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:450)
        at org.eclipse.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:403)
        at com.wordnik.swagger.core.util.JsonSerializer$.<init>(JsonSerializer.scala:31)
        at com.wordnik.swagger.core.util.JsonSerializer$.<clinit>(JsonSerializer.scala)
        at org.apache.camel.component.swagger.RestSwaggerApiDeclarationServlet.renderResourceListing(RestSwaggerApiDeclarationServlet.scala:225)
        at org.apache.camel.component.swagger.RestSwaggerApiDeclarationServlet.doGet(RestSwaggerApiDeclarationServlet.scala:111)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)

when the same url is called a second time, then we get another class not found error

2015-08-05 17:47:33.803:WARN:oejs.ServletHandler:qtp1891031939-33: Error for /camel-example-servlet-rest-tomcat/api-docs/myCamel
java.lang.NoClassDefFoundError: Could not initialize class com.wordnik.swagger.core.util.JsonSerializer$
        at org.apache.camel.component.swagger.RestSwaggerApiDeclarationServlet.renderResourceListing(RestSwaggerApiDeclarationServlet.scala:225)
        at org.apache.camel.component.swagger.RestSwaggerApiDeclarationServlet.doGet(RestSwaggerApiDeclarationServlet.scala:111)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
        at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:808)
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1669)
        at org.apache.camel.component.swagger.RestSwaggerCorsFilter.doFilter(RestSwaggerCorsFilter.scala:44)
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)
        at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:585)
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
        at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:577)
        at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)
        at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127)
        at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
        at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
        at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061)
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
        at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:215)
        at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:110)
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
        at org.eclipse.jetty.server.Server.handle(Server.java:497)
        at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:310)
        at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:257)
        at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540)
        at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635)
        at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555)
        at java.lang.Thread.run(Thread.java:745)