[appengine-java] Newbie: java.lang.ClassNotFoundException
Hello, all!
A friend and I are dabbling in App Engine using the Java SDK. We've
put together a Hello, World example with no problems; however, when
we try to add code to make a simple call to a webservice using the
classes in com.google.api.client.http, our code compiles fine but
causes a runtime error:
HTTP ERROR 500
Problem accessing /surreality. Reason:
com/google/api/client/http/HttpTransport
Caused by:
HTTP ERROR 500
Problem accessing /surreality. Reason:
com/google/api/client/http/javanet/NetHttpTransport
Caused by:
java.lang.NoClassDefFoundError: com/google/api/client/http/javanet/
NetHttpTransport
at
com.surreality.scratch.SurrealityServlet.performSearch(SurrealityServlet.java:
31)
at
com.surreality.scratch.SurrealityServlet.doGet(SurrealityServlet.java:
18)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:
511)
(...cut)
The code in question is:
package com.surreality.scratch;
import java.io.IOException;
import javax.servlet.http.*;
import java.util.List;
import com.google.api.client.googleapis.*;
import com.google.api.client.http.*;
import com.google.api.client.http.javanet.*;
import com.google.api.client.util.Key;
@SuppressWarnings(serial)
public class SurrealityServlet extends HttpServlet {
public void doGet(HttpServletRequest req, HttpServletResponse resp)
throws IOException {
resp.setContentType(text/plain);
try {
this.performSearch(resp);
resp.getWriter().println(Here...);
} catch (Exception e) {
resp.getWriter().println(Onoes!);
}
}
public void performSearch(HttpServletResponse resp) throws Exception
{
try {
resp.getWriter().println(Perform Search );
resp.getWriter().println(---);
HttpTransport transport = new NetHttpTransport(); //
This line
causes our servlet to implode on every request
} catch (Exception e) {
resp.getWriter().println(failed);
throw e;
}
}
}
Our best guess was a discrepancy between the build classpath and the
runtime classpath, but our runtime classpath *seems* to be OK. The
HttpTransport class is in the google-api-client-1.4.1-beta.jar
library, and that's included in the command line Eclipse is generating
to run the project:
/System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/bin/
java -Ddatastore.default_high_rep_job_policy_unapplied_job_pct=50 -
Xmx512m -javaagent:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/agent/appengine-agent.jar -
XstartOnFirstThread -Xbootclasspath/p:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/override/appengine-dev-jdk-overrides.jar -
Dfile.encoding=MacRoman -classpath /Users/Arkaaito/Documents/AppEngine/
scratch/surreality/war/WEB-INF/classes:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/appengine-local-runtime-
shared.jar:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/el-api.jar:/Applications/eclipse/
plugins/com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/jsp/repackaged-appengine-
ant-1.7.1.jar:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/jsp/repackaged-appengine-ant-
launcher-1.7.1.jar:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/jsp/repackaged-appengine-
jasper-6.0.29.jar:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/jsp/repackaged-appengine-jasper-
el-6.0.29.jar:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/jsp/repackaged-appengine-tomcat-
juli-6.0.29.jar:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/jsp-api.jar:/Applications/eclipse/
plugins/com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/servlet-api.jar:/Applications/
eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/user/appengine-api-1.0-sdk-1.5.3.jar:/
Applications/eclipse/plugins/
Re: [appengine-java] Newbie: java.lang.ClassNotFoundException
Hi
Did you try using URLFetch ?
Check this post from Ikai
http://ikaisays.com/2010/06/29/using-asynchronous-urlfetch-on-java-app-engine/
Regards,
On Sun, Sep 18, 2011 at 7:46 PM, Arkaaito alsti...@gmail.com wrote:
Hello, all!
A friend and I are dabbling in App Engine using the Java SDK. We've
put together a Hello, World example with no problems; however, when
we try to add code to make a simple call to a webservice using the
classes in com.google.api.client.http, our code compiles fine but
causes a runtime error:
HTTP ERROR 500
Problem accessing /surreality. Reason:
com/google/api/client/http/HttpTransport
Caused by:
HTTP ERROR 500
Problem accessing /surreality. Reason:
com/google/api/client/http/javanet/NetHttpTransport
Caused by:
java.lang.NoClassDefFoundError: com/google/api/client/http/javanet/
NetHttpTransport
at
com.surreality.scratch.SurrealityServlet.performSearch(SurrealityServlet.java:
31)
at
com.surreality.scratch.SurrealityServlet.doGet(SurrealityServlet.java:
18)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at
org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:
511)
(...cut)
The code in question is:
package com.surreality.scratch;
import java.io.IOException;
import javax.servlet.http.*;
import java.util.List;
import com.google.api.client.googleapis.*;
import com.google.api.client.http.*;
import com.google.api.client.http.javanet.*;
import com.google.api.client.util.Key;
@SuppressWarnings(serial)
public class SurrealityServlet extends HttpServlet {
public void doGet(HttpServletRequest req, HttpServletResponse resp)
throws IOException {
resp.setContentType(text/plain);
try {
this.performSearch(resp);
resp.getWriter().println(Here...);
} catch (Exception e) {
resp.getWriter().println(Onoes!);
}
}
public void performSearch(HttpServletResponse resp) throws Exception
{
try {
resp.getWriter().println(Perform Search );
resp.getWriter().println(---);
HttpTransport transport = new NetHttpTransport(); //
This line
causes our servlet to implode on every request
} catch (Exception e) {
resp.getWriter().println(failed);
throw e;
}
}
}
Our best guess was a discrepancy between the build classpath and the
runtime classpath, but our runtime classpath *seems* to be OK. The
HttpTransport class is in the google-api-client-1.4.1-beta.jar
library, and that's included in the command line Eclipse is generating
to run the project:
/System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/bin/
java -Ddatastore.default_high_rep_job_policy_unapplied_job_pct=50 -
Xmx512m -javaagent:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/agent/appengine-agent.jar -
XstartOnFirstThread -Xbootclasspath/p:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/override/appengine-dev-jdk-overrides.jar -
Dfile.encoding=MacRoman -classpath /Users/Arkaaito/Documents/AppEngine/
scratch/surreality/war/WEB-INF/classes:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/appengine-local-runtime-
shared.jar:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/el-api.jar:/Applications/eclipse/
plugins/com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/jsp/repackaged-appengine-
ant-1.7.1.jar:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/jsp/repackaged-appengine-ant-
launcher-1.7.1.jar:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/jsp/repackaged-appengine-
jasper-6.0.29.jar:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/jsp/repackaged-appengine-jasper-
el-6.0.29.jar:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/jsp/repackaged-appengine-tomcat-
juli-6.0.29.jar:/Applications/eclipse/plugins/
com.google.appengine.eclipse.sdkbundle_1.5.3.r37v201108301710/
appengine-java-sdk-1.5.3/lib/shared/jsp-api.jar:/Applications/eclipse/
