H2 Database connection timeout with new computer

Question

I'm using two H2 databases in my Java projects. Recently, I changed my computer and since then I have no problem with connecting to one of those databases using my Java code but problems with the other one. It's exactly the same code (up to PATH_TO_DATABASE) I use to start the connection:

import java.sql.DriverManager;
import java.sql.SQLException;

public class DatabaseConfig {

    private static java.sql.Connection connection;

    public static void init() {
        if (connection == null) {
            try {
                connection = DriverManager.getConnection("jdbc:h2:tcp://192.168.178.50:9092/C:/Users/PATH_TO_DATABASE", "USER", "PW");
            } catch (SQLException e) {
                System.err.println("SQLException");
                e.printStackTrace();
                System.exit(0);
            }
        }
    }

    [...]
}

This is the stack trace I get:

SQLException
org.h2.jdbc.JdbcSQLException: Connection is broken: "java.net.SocketTimeoutException: connect timed out: 192.168.178.21:9092" [90067-196]
    at org.h2.message.DbException.getJdbcSQLException(DbException.java:345)
    at org.h2.message.DbException.get(DbException.java:168)
    at org.h2.engine.SessionRemote.connectServer(SessionRemote.java:457)
    at org.h2.engine.SessionRemote.connectEmbeddedOrServer(SessionRemote.java:334)
    at org.h2.jdbc.JdbcConnection.<init>(JdbcConnection.java:116)
    at org.h2.jdbc.JdbcConnection.<init>(JdbcConnection.java:100)
    at org.h2.Driver.connect(Driver.java:69)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at data.DatabaseConfig.init(DatabaseConfig.java:20)
    ...
Caused by: java.net.SocketTimeoutException: connect timed out
    at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
    at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
    at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
    at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
    at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
    at java.net.PlainSocketImpl.connect(Unknown Source)
    at java.net.SocksSocketImpl.connect(Unknown Source)
    at java.net.Socket.connect(Unknown Source)
    at org.h2.util.NetUtils.createSocket(NetUtils.java:103)
    at org.h2.util.NetUtils.createSocket(NetUtils.java:83)
    at org.h2.engine.SessionRemote.initTransfer(SessionRemote.java:115)
    at org.h2.engine.SessionRemote.connectServer(SessionRemote.java:453)
    ... 8 more

Using the web interface I can connect to both databases easily.

I'm a little bit lost here since I can't figure out what's going wrong with one of the databases. The strange thing is that everything works fine with the other database.

EDIT: I just realized that the IP address in the error message is different from the one in the code (192.168.178.21:9092 vs. 192.168.178.50:9092). Maybe this is th ereason of the error. The one in the code is the correct IP address. Why do I get a different one in the error message? Is that the reason of my problem?

Answer 1

If it's a remote connection, do an ipconfig to find out if the 192.168.xx address is changed.

If it's a local connection, you can simplify your URL as

jdbc:h2:~/PATH_TO_DATABASE

Answer 2

I just solved the problem (it was kind of my stupidity): The project couldn't build on the new computer because the H2 jar was not properly included in the build path. That's why eclipse called all the time the old .class file and hence tried to connect to the old computer (192.168.178.21:9092) instead to the new one (192.168.178.50:9092). I didn't realize that eclipse didn't compile and was executing old stuff.