I have 2 projects in Eclipse.
The first project calls a method from the second project handing it an object the second project shall write into an existing SQLite Database residing in the second project.
However, I get the following error:
opening db: 'tomato.db': Zugriff verweigert
Zugriff verweigert is German for access denied.
How can I allow the db access from the first project to the database file tomato.db residing in the second project?
Solution
I use sqlite-jdbc from xerial.
In their tutorial they get the database connection with this line:
connection = DriverManager.getConnection("jdbc:sqlite:yourdatabasefile.db");
However, this doesn't work from another project in Eclipse.
The solution is actually pretty trivial:
connection = DriverManager.getConnection("jdbc:sqlite:C:\\path\\to\\your\\database\\file\\yourdatabasefile.db");
Another solution is to use the in-memory sqlite database like this:
connection = DriverManager.getConnection("jdbc:sqlite::memory:");
Hope this helps.
Related
I have a project assignment in which I have to create a Java application. The program must be uploaded to my GitHub repository so my professor can see it and interact with it.
I have the following problem: For the purposes of the application I have to use a database. I decided to work with a Java Derby embedded database. So here an example of my code where I connect with the database:
String Table_click = (jTable1.getModel().getValueAt(row, 0).toString());
Class.forName("org.apache.derby.jdbc.EmbeddedDriver");
java.sql.Connection con=DriverManager.getConnection("jdbc:derby:C:\\Users\\themi\\OneDrive\\Desktop\\HRCompanion\\databases\\Login", "root", "1234");
As you can see, my database is stored inside the project folder on my computer. But if I upload this code to GitHub, then my professor will not be able to run the application properly, as the database path does not exist. Is there a way to change the path to make the application work properly to a different computer?
You can use a relative path in your JDBC Connection URL.
So, for example, jdbc:derby:db means that Derby will look for the database in the db folder in the current directory.
Then you won't have such a problem with system-specific pathnames.
I am creating a Hibernate project in IntelliJ IDE and trying to hook it up with a H2 database. I created the project based upon this tutorial:
http://www.roseindia.net/hibernate/hibernate4.2/hibernate-example-step-by-step-in-eclipse.shtml
The only change I'm making is the database, instead of MySQL, I'm using H2. However, when I'm trying to run the application, the insertion to the database is shown to have been successful, but there are no signs of any such rows when I open up the database in the H2 console. I've tried many solutions suggested here and elsewhere, including this, this and this. I've tried changing the connection URL of the database in the hibernate.cfg.xml file from a relative path to absolute path, but to no avail. I'm attaching a screenshot of my hibernate.cfg.xml and the relevant portion of the log below. Please help me out with this.
your hibernate.connection.url should be something like that jdbc:h2:tcp://localhost/mem:playground I am assuming you are starting the H2 database out of your project, as you are connecting to H2 via console.
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.
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.
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.