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Get JDBC connection working in play framework (java)

Was wondering, what steps am I missing to get a jdbc embeded h2 database working in my play application? Following these docs.
So far editted Application.conf file to contain this:
db.default.driver=org.h2.Driver
db.default.url="jdbc:h2:databases/test"
db.default.user=test
db.default.password="testtest"
Next I created a libs directory and added the jar file
h2-1.3.174.jar
Is this necessary or does the provided driver handle all types of h2 databases (embeded and server - I know it handles in memory)?
Now in the controler how can I access the database? Do I have to start/shutdown the database?
I know I can get connections from the getConnection() method in play.db. But everytime I execute a statement through this connection I get an exception saying no data is available. If I then check - looks like directory
databases/test
was not created so no database files exist.
What am I missing?

H2 works out of the box. Just create a new project in the terminal.
Otherwise, to your listing:
I think you should change db.default.url="jdbc:h2:databases/test" to db.default.url="jdbc:h2:mem:play"
don't need to create lib directories. It's all handeled by the build in dependency mgmt sbt
Just use the model objects and call save/update. No need to call start/shutdown
you are in a framework, it's all there ready for you...
I think you should start reading the documentation from the beginning to the end and examine the example applications. It's all there what you are looking for.

In addition to myborobudur's answer I'll only mention, that you don't need to use memory database, as you can for an instance use file storage (Embedded) or even run H2 as a server and then connect to it with TCP in Server Mode... Everything is clearly described in H2 documentation.

Get messages.log style logging out of embedded neo4j

How can I maximize the log information an embedded neo4j database will give me, so that I can see what's going on?
Recent technical discussion on the google group called for an excerpt of messages.log, but I don't have that log file since I'm running embedded. I have consulted the server configuration docs (http://docs.neo4j.org/chunked/stable/server-configuration.html#_server_logging_configuration) but they don't tell me the actual names of the loggers to use.
I have tried this:
java.util.logging.Logger.getLogger("org.neo4j").setLevel(Level.ALL)
But by default, and also with this line of code, I see no log messages from neo4j at all.
I'm trying to get some of the server message logs to debug why certain read-only transactions are failing and rollback is failing; first I have to figure out how to get neo4j to tell me what's going on in this embedded database.

Actually you have messages.log it is in your graph.db directory.
And there are loads of diagnostic, config, tuning, memory and other information in that file. So very valuable.

JDBC and Sql Server 2008 Connectivity

I am accessing an SQL server 2008 Database through JDBC4.0. the problem is I can access my DB just when my glassfish server is restarted, it run the code normally but once, if i make any changes into the code i have to restart the glassfish server otherwise it generate the following error.
WARNING: Failed to load the sqljdbc_auth.dll cause : Native Library C:\Windows\System32\sqljdbc_auth.dll already loaded in another classloader
Kindly guide me what should i do to solve this problem i am using Eclipse editor. and my code is
String url = "jdbc:sqlserver://localhost;databaseName=ProductDB; integratedSecurity=true;";
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver").newInstance();
con = DriverManager.getConnection(url);
System.out.println("Connected");

If you have a data source correctly defined in GlassFish you should be able to simply re-deploy your application in order to see changes to .java files (you can even use hot deploy although my experience with that has been less than great). XML files shouldn't even need a redeploy.
Update: I see from your edit you are loading the driver etc manually. I suggest you let GlassFish manage the data source and use resource injection to acquire a connection.
Edit: Re-reading your question properly... you don't need the sqljdbc_quth.dll library if you are using sql authentication but it will speeds up authentication with the sql server. I tried it out with one of our products but it didn't make any noticeable difference so I've not bothered since.

If you do any changes in xml or .java file definitely you have to restart.
If you use re loadable resource-bundle to read properties file its ok.
Updated :
Just go to Project in top bar than check "Build Automatically". It will stop auto building the project and saves your precious time.

Best way to access a sqlite database file in a web service

First question from me on stack overflow.
I have created a java web application containing a web service using netbeans (I hope a web application were the correct choice). I use the web application as is with no extra frameworks. This web service use a sqlite JDBC driver for accessing a sqlite database file.
My problem is that the file path end up incorrect when I try to form the JDBC connection string. Also, the working directory is different when deploying and when running JUnit tests. I read somewhere about including the file as a resource, but examples of this were nowhere to be seen.
In any case, what is the best way to open the sqlite database, both when the web service is deployed and when I test it "locally"?
I don't know much about web services, I just need it to work, so please, help me with the technicalities.
Update
To put this a litle bit in context, some "println" code gives this:
Printing the work directory from a simple JUnit test gives
C:\MinaFiler\Work\SOA\BusTimetableWS
Invoking a similar web servic method returns
C:\Program Files\sges-v3\glassfish\domains\domain1
The connection string is formed from prepending "jdbc:sqlite:" to the path which at the moment is absolute:
C:\MinaFiler\Work\SOA\BusTimetableWS\src\java\miun\bustimetable\database\sqlit\BusTimetableWS.db
However, this fails because my tests throws exceptions stating database tables doesn't exist although they really do, I can see them with sqlite3.exe .

One way would be to use a config file that you can read and fetch your connection string from there.
I'm sure the framework you are using has some kind of standard way of saving configurations.
Another option would be to place the db in a known relative path from your main execution files. Then when executed fetch your current directory, and look for the db from that path.

In any case, what is the best way to open the sqlite database, both when the web service is deployed and when I test it "locally"?
The web service should use a DataSource to retrieve a connection from a connection pool configured at the application server level. In your unit test, use whatever you want (a standalone connection pool, a direct JDBC connection).
But in both cases, why don't you use an absolute path to the database file in your jdbc url? From How to Specify Database Files:
jdbc:sqlite:C:/work/mydatabase.db
The working directory wouldn't matter if you do so.

In toplink and struts 2 based application, even after commiting data data disappears from the database

I have a struts 2 application and a toplink persistence provider running on tomcat 6.0.20 and a MySql 5.1.38 server on a GNU/Linux machine. After committing the data the when i go to retrieve it the data it has disappeared from the database.
I do a em.commit() and em.flush() after my queries have executed. How do they disappear? I am using all standard configuration files. I have reduced the wait_timeout and the interactive_timout period in mysql. Also am using autoReconnectforPools in my persistence.xml.
I also invalidate the cache on every users logout.
Any ideas?

anyway it does not matter, the problem was solved by removing softweak from persistence.xml's entity type declaration and adding hardweak in its place.