I was hopeful that Jersey would deploy easily to Google App Engine, as it is supposedly supported ( http://code.google.com/p/googleappengine/wiki/WillItPlayInJava ) and several people mention they made it work ( http://tugdualgrall.blogspot.ca/2010/02/create-and-deploy-jax-rs-rest-service.html) But it does not work...
I added to my web.xml :
<servlet>
<servlet-name>Jersey REST Service</servlet-name>
<servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
<init-param>
<param-name>com.sun.jersey.config.property.packages</param-name>
<param-value>sample.hello.resources</param-value>
</init-param>
<init-param>
<param-name>com.sun.jersey.config.feature.DisableWADL</param-name>
<param-value>true</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
I added to the classpath : jersey-bundle-1.14.jar (I even tried with only core, servlet, and server AND I even tried with 1.5 only)
but I still get stuck with this :
WARNING: failed Jersey REST Service: java.lang.IncompatibleClassChangeError: Implementing class
Oct 27, 2012 6:17:06 PM com.google.apphosting.utils.jetty.JettyLogger warn
WARNING: failed com.google.appengine.tools.development.DevAppEngineWebAppContext@68c12474{/,/Users/anthony/workspaces/gae/restfulapp/war}: java.lang.IncompatibleClassChangeError: Implementing class
Oct 27, 2012 6:17:06 PM com.google.apphosting.utils.jetty.JettyLogger warn
WARNING: failed JettyContainerService$ApiProxyHandler@365878d2: java.lang.IncompatibleClassChangeError: Implementing class
Oct 27, 2012 6:17:06 PM com.google.apphosting.utils.jetty.JettyLogger warn
WARNING: Error starting handlers
java.lang.IncompatibleClassChangeError: Implementing class
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)
at java.lang.ClassLoader.defineClass(ClassLoader.java:615)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)
at java.net.URLClassLoader.access$000(URLClassLoader.java:58)
at java.net.URLClassLoader$1.run(URLClassLoader.java:197)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at com.google.appengine.tools.development.IsolatedAppClassLoader.loadClass(IsolatedAppClassLoader.java:207)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
at com.sun.jersey.api.core.ScanningResourceConfig.init(ScanningResourceConfig.java:79)
at com.sun.jersey.api.core.PackagesResourceConfig.init(PackagesResourceConfig.java:104)
at com.sun.jersey.api.core.PackagesResourceConfig.<init>(PackagesResourceConfig.java:78)
at com.sun.jersey.api.core.PackagesResourceConfig.<init>(PackagesResourceConfig.java:89)
at com.sun.jersey.spi.container.servlet.WebComponent.createResourceConfig(WebComponent.java:696)
at com.sun.jersey.spi.container.servlet.WebComponent.createResourceConfig(WebComponent.java:674)
at com.sun.jersey.spi.container.servlet.WebComponent.init(WebComponent.java:206)
at com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:373)
at com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:556)
at javax.servlet.GenericServlet.init(GenericServlet.java:212)
at org.mortbay.jetty.servlet.ServletHolder.initServlet(ServletHolder.java:440)
at org.mortbay.jetty.servlet.ServletHolder.doStart(ServletHolder.java:263)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:685)
at org.mortbay.jetty.servlet.Context.startContext(Context.java:140)
at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1250)
at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:517)
at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:467)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
at org.mortbay.jetty.Server.doStart(Server.java:224)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
at com.google.appengine.tools.development.JettyContainerService.startContainer(JettyContainerService.java:205)
at com.google.appengine.tools.development.AbstractContainerService.startup(AbstractContainerService.java:249)
at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerImpl.java:157)
at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:333)
at com.google.appengine.tools.util.Parser$ParseResult.applyArgs(Parser.java:48)
at com.google.appengine.tools.development.DevAppServerMain.<init>(DevAppServerMain.java:269)
at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMain.java:245)
What did I miss ? Should I use another jax-rs implementation for gae ? Thanks for your answers !
OK, I found out : apparently (looking at the stack trace I posed on the question) , GAE did not allow Jersey to use its classloader to scan the available rest resources. So, I read in detail the Jersey documentation the Jersey documentation regarding the deployments and I found out that I can manually specify theRest resources to Jersey.
Here is the web.xml :
<servlet-mapping>
<servlet-name>Jersey Web Application</servlet-name>
<url-pattern>/rest/*</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>Jersey Web Application</servlet-name>
<servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer
</servlet-class>
<init-param>
<param-name>javax.ws.rs.Application</param-name>
<param-value>sample.hello.bean.MyApplication</param-value>
</init-param>
</servlet>
You can notice I now have an Application class :
package sample.hello.bean;
import java.util.HashSet;
import java.util.Set;
import javax.ws.rs.core.Application;
import sample.hello.resources.HelloResource;
public class MyApplication extends Application {
public Set<Class<?>> getClasses() {
Set<Class<?>> s = new HashSet<Class<?>>();
s.add(HelloResource.class);
return s;
}
}
Just specify manually your rest resources adding them to the set.