Java Web App Crashing on Heroku

Question

I have an existing Java web app project. I converted it into a maven project and deployed it on Heroku. The application is deployed successfully but it does not run; it crashes. I cannot figure out from the logs what the reason is. my Procfile looks like this: web: java $JAVA_OPTS -cp target/classes:target/m2e-wtp/*.jar

All I see in the logs is that the app crashed with the error code = H10 with status 503. I would really appreciate help on this.Following are the logs:

app[web.1]: See http://www.oracle.com/technetwork/java/javase/documentation/index.html for more details.
heroku[web.1]: State changed from starting to crashed
heroku[web.1]: Process exited with status 1
heroku[api]: Scale to web=1 by charan7j86@gmail.com
heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=fierce-woodland-8040.herokuapp.com request_id=9e462e2f-0e4f-4ef7-a503-e557fa46397a fwd="67.169.27.222" dyno= connect= service= status=503 bytes=
heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=fierce-woodland-8040.herokuapp.com request_id=fcfb168d-3c62-4c0b-92ba-0a0418cdc703 fwd="67.169.27.222" dyno= connect= service= status=503 bytes=
heroku[web.1]: State changed from crashed to starting
heroku[web.1]: Starting process with command `java -XX:+UseCompressedOops -cp target/classes:target/m2e-wtp/*.jar`
app[web.1]: Usage: java [-options] class [args...]
app[web.1]:            (to execute a class)
app[web.1]:    or  java [-options] -jar jarfile [args...]
app[web.1]:            (to execute a jar file)
app[web.1]: where options include:
app[web.1]:     -d32      use a 32-bit data model if available
app[web.1]:     -d64      use a 64-bit data model if available
app[web.1]:                   The default VM is server,
app[web.1]:     -server      to select the "server" VM
app[web.1]:                   because you are running on a server-class machine.
app[web.1]: 
app[web.1]:     -cp <class search path of directories and zip/jar files>
app[web.1]: 
app[web.1]:     -classpath <class search path of directories and zip/jar files>
app[web.1]:                   A : separated list of directories, JAR archives,
app[web.1]:                   and ZIP archives to search for class files.
app[web.1]:     -D<name>=<value>
app[web.1]:                   set a system property
app[web.1]:     -verbose:[class|gc|jni]
app[web.1]:                   enable verbose output
app[web.1]:     -version      print product version and exit
app[web.1]:     -version:<value>
app[web.1]:                   require the specified version to run
app[web.1]:     -showversion  print product version and continue
app[web.1]:     -jre-restrict-search | -no-jre-restrict-search
app[web.1]:                   include/exclude user private JREs in the version search
app[web.1]:     -? -help      print this help message
app[web.1]:     -X            print help on non-standard options
app[web.1]:     -ea[:<packagename>...|:<classname>]
app[web.1]:     -enableassertions[:<packagename>...|:<classname>]
app[web.1]:                   enable assertions with specified granularity
app[web.1]:     -disableassertions[:<packagename>...|:<classname>]
app[web.1]:     -da[:<packagename>...|:<classname>]
app[web.1]:     -esa | -enablesystemassertions
app[web.1]:                   disable assertions with specified granularity
app[web.1]:                   enable system assertions
app[web.1]:     -dsa | -disablesystemassertions
app[web.1]:                   disable system assertions
app[web.1]:     -agentlib:<libname>[=<options>]
app[web.1]:                   load native agent library <libname>, e.g. -agentlib:hprof
app[web.1]:                   see also, -agentlib:jdwp=help and -agentlib:hprof=help
app[web.1]:     -agentpath:<pathname>[=<options>]
app[web.1]:                   load native agent library by full pathname
app[web.1]:     -javaagent:<jarpath>[=<options>]
app[web.1]:                   load Java programming language agent, see java.lang.instrument
app[web.1]:     -splash:<imagepath>
app[web.1]:                   show splash screen with specified image
app[web.1]: See http://www.oracle.com/technetwork/java/javase/documentation/index.html for more details.
heroku[web.1]: Process exited with status 1
heroku[web.1]: State changed from starting to crashed

Answer 1

The command in your Procfile doesn't specify a Main class. It should look like:

 web: java $JAVA_OPTS -cp target/classes:target/m2e-wtp/*.jar com.foo.Main