play! + GAE+ JPA

[yuanchangjun]

I am a newer, I don't know how to configure jpa in google app engine?

Hint:
Exception in thread "main" play.exceptions.JPAException: Cannot start
a JPA manager without a properly configured database
at play.db.jpa.JPAPlugin.onApplicationStart(JPAPlugin.java:33)
at play.Play.start(Play.java:338)
at play.Play.init(Play.java:199)
at play.server.Server.main(Server.java:58)
Caused by: java.lang.NullPointerException: No datasource
... 4 more
Java Result: 1

[Lynn Peng]

Comment all DB setting in application.conf, and add this:

module.gae=${play.path}/modules/gae


Hope it works for you.

[袁长军]

I comment all DB setting in application.conf, and add this: module.gae=${play.path}/modules/gae,  but it don't work for me!

This is my application.conf:

# This is the main configuration file for the application.

# ~~~~~

#

application.name=play_demo

# Application mode

# ~~~~~

# Set to dev to enable instant reloading and other development help.

# Otherwise set to prod.

#

application.mode=dev

# application.mode=prod

# Secret key

# ~~~~~

# The secret key is used to secure cryptographics functions

# If you deploy your application to several instances be sure to use the same key !

#

application.secret=1hsoz0insmvlbfh5zd6mbf3cftdtuwdq6zpo4ez020ayyga959jd0nocu4h8tt5p

# Additional modules

# ~~~~~

# A module is another play! application. Add a line for each module you want

# to add to your application. Modules path are either absolutes or relative to

# the application root.

#

#module.ecss=${play.path}/modules/ecss

module.crud=${play.path}/modules/crud

module.gae=${play.path}/modules/gae

# i18n

# ~~~~~

# Define locales used by your application.

# You can then place localized messages in conf/messages.{locale} files

#

# application.langs=fr,en,ja

# Server configuration

# ~~~~~

# If you need to change the HTTP port, uncomment this (default is set to 9000)

#

# http.port=9000

# JPDA configuration

# ~~~~~

# Define which port is used by JPDA when application is in debug mode (default is set to 8000)

#

# jpda.port=8000

# Log level

# ~~~~~

# Specify log level for your application.

# If you want a very customized log, create a log4j.properties file in the conf directory

#

# application.log=INFO

# Database configuration

# ~~~~~ 

# Enable a database engine if needed.

# There are two built in values :

#   - mem : for a transient in memory database (HSQL in memory)

#   - fs  : for a simple file written database (HSQL file stored)

#

# db=mem

#

# If you need a full jdbc configuration use the following :

#

# db.url=jdbc:mysql://localhost/test

# db.driver=com.mysql.jdbc.Driver

# db.user=root

# db.pass=

#

# Connections pool configuration :

#

# db.pool.timeout=1000

# db.pool.maxSize=30

# db.pool.minSize=10

# JPA Configuration (hibernate)

# ~~~~~

#

# Specify the custom JPA dialect to use here (default to guess) :

# jpa.dialect=org.hibernate.dialect.MySQLDialect

#

# Specify the ddl generation pattern to use (default to update) :

# jpa.ddl=update

#

# Debug SQL statements :

# jpa.debugSQL=true

############################### Google App Engine ##############################

# jpa.dialect=play.modules.gae.DataNucleusDialect

# Memcached configuration

# ~~~~~ 

# Enable memcached if needed. Otherwise a local cache is used.

# memcached=enabled

#

# Specify memcached host (default to 127.0.0.1:11211)

# memcached.host=127.0.0.1:11211

#

# Or you can specify multiple host to build a distributed cache

# memcached.1.host=127.0.0.1:11211

# memcached.2.host=127.0.0.1:11212

# Mail configuration

# ~~~~~ 

# Default is to use a mock Mailer

mail.smtp=mock

# Or, specify mail host configuration

# mail.smtp.host=127.0.0.1

# mail.smtp.user=admin

# mail.smtp.pass=

# mail.smtp.channel=ssl

# Open file from errors pages

# ~~~~~

# If your text editor supports to open files using URL, Play! will link

# error pages to files dynamically

#

# play.editor=txmt://open?url=file://%s&line=%s

# Testing. Set up a custom configuration for test mode

# ~~~~~

%test.application.mode=dev

%test.db=mem

%test.jpa.ddl=create-drop

%test.mail.smtp=mock

This is my starting Info:

nb-run-application:

D:\play-1.0-stable6\id doesn't exist

Listening for transport dt_socket at address: 8000

09:21:34,328 INFO  ~ 

09:21:34,343 INFO  ~ Starting E:\play_demo

09:21:34,359 INFO  ~ Module crud is available (D:\play-1.0-stable6\modules\crud)

09:21:34,359 INFO  ~ Module gae is available (D:\play-1.0-stable6\modules\gae)

09:21:34,531 WARN  ~ You're running Play! in DEV mode

09:21:34,531 INFO  ~ Application 'play_demo' is ready !

09:21:34,781 INFO  ~ Listening for HTTP on port 9000 ...

09:21:57,671 ERROR ~ 

@5pl0a7nln

For request GET /

Internal Server Error (500)

JPA error

A JPA error occured (Cannot start a JPA manager without a properly configured database): No datasource

play.exceptions.JPAException: Cannot start a JPA manager without a properly configured database

        at play.db.jpa.JPAPlugin.onApplicationStart(JPAPlugin.java:33)

        at play.Play.start(Play.java:338)

        at play.Play.detectChanges(Play.java:403)

        at play.Invoker$Invocation.before(Invoker.java:62)

        at play.Invoker$Invocation.doIt(Invoker.java:109)

        at play.server.HttpHandler$MinaInvocation.doIt(HttpHandler.java:387)

        at play.Invoker.invokeInThread(Invoker.java:44)

        at play.server.HttpHandler.messageReceived(HttpHandler.java:80)

        at Play!.HTTP Server(Mina)

Caused by: java.lang.NullPointerException: No datasource

        ... 9 more

09:21:58,000 ERROR ~