I'm trying to connect to HSQL using java. I'm using a tutorial to work with JDBC and hibernate. It's the lynda tutorials. Anyway, here's the code below:
package com.lynda.javatraining.db;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class Main {
private static final String USERNAME = "dbuser";
private static final String PASSWORD = "dbpassword";
private static final String CONN_STRING =
"jdbc:hsqldb://data/explorecalifornia";
public static void main(String[] args) throws SQLException {
//Class.forName("com.mysql.jdbc.Driver");
Connection conn = null;
System.out.println("A");
System.out.println(conn == null);
System.out.println(CONN_STRING);
try {
System.out.println("B1");
conn = DriverManager.getConnection(CONN_STRING, USERNAME, PASSWORD);
System.out.println("B1-2");
System.out.println("Connected!");
} catch (SQLException e) {
System.out.println("B2");
System.err.println(e);
} finally {
System.out.println("B3");
if (conn != null) {
conn.close();
}
}
System.out.println("C");
}
}
Here's the error I'm getting:
A
true
jdbc:hsqldb://data/explorecalifornia
B1
2014-06-27T15:26:27.430-0400 SEVERE could not reopen database
org.hsqldb.HsqlException: Database lock acquisition failure: lockFile: org.hsqldb.persist.LockFile#76d682a[file =/data/explorecalifornia.lck, exists=false, locked=false, valid=false, ] method: openRAF reason: java.io.FileNotFoundException: /data/explorecalifornia.lck (No such file or directory)
at org.hsqldb.error.Error.error(Unknown Source)
at org.hsqldb.error.Error.error(Unknown Source)
at org.hsqldb.persist.LockFile.newLockFileLock(Unknown Source)
at org.hsqldb.persist.Logger.acquireLock(Unknown Source)
at org.hsqldb.persist.Logger.openPersistence(Unknown Source)
at org.hsqldb.Database.reopen(Unknown Source)
at org.hsqldb.Database.open(Unknown Source)
at org.hsqldb.DatabaseManager.getDatabase(Unknown Source)
at org.hsqldb.DatabaseManager.newSession(Unknown Source)
at org.hsqldb.jdbc.JDBCConnection.<init>(Unknown Source)
at org.hsqldb.jdbc.JDBCDriver.getConnection(Unknown Source)
at org.hsqldb.jdbc.JDBCDriver.connect(Unknown Source)
at java.sql.DriverManager.getConnection(DriverManager.java:571)
at java.sql.DriverManager.getConnection(DriverManager.java:215)
at com.lynda.javatraining.db.Main.main(Main.java:24)
B2
java.sql.SQLException: Database lock acquisition failure: lockFile: org.hsqldb.persist.LockFile#76d682a[file =/data/explorecalifornia.lck, exists=false, locked=false, valid=false, ] method: openRAF reason: java.io.FileNotFoundException: /data/explorecalifornia.lck (No such file or directory)
B3
C
Can anyone tell e what I"m doing wrong? Thanks.
A database has a lock file explorecalifornia.lck that prevents communication. You should delete lock file and restart the database. This may happens from time to time when you accidentally shutdown the database or system.
See the syntax of the command used from the command line to invoke shutdown. There's also an option how to shutdown server in Java.
Related
I'm trying to connect to an external database and no matter what I do I keep getting the following error:
java.lang.ClassNotFoundException: com.microsoft.sqlserver.jdbc.SQLServerDriver
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at DbCon.main(DbCon.java:10)
My code to set up the driver:
import java.sql.*;
public class DbCon {
public static void main(String[] args) {
try {
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
} catch (ClassNotFoundException e1) {
e1.printStackTrace();
}
}
}
I've tried omitting the driver entirely, and just trying to connect with:
String connectionUrl = "jdbc:sqlserver://xxx.xxx.xxx.xxx:1433;databaseName=xxxx;user=xxxx;password=xxxx;";
try {
Connection con = DriverManager.getConnection(connectionUrl);
} catch (SQLException e) {
e.printStackTrace();
}
This only gets me the following error:
java.sql.SQLException: No suitable driver found for xxxx
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at DbCon.main(DbCon.java:15)
I've tried adding the jar to Eclipse's classpath, I've added the folder to the project's build path as an external class folder.
Is there something I'm missing?
I do not want to install a database server on target machine. It is possible that we can simply ship a jar file with the database embedded in it, and not worry about installing a database server separately?
I created one application in netbeans using derby and it is working fine in my pc but when i am running on other machine it is giving me an Exception
My code is
System.setProperty("derby.drda.startNetworkServer", "true");
try {
NetworkServerControl serverControl = new NetworkServerControl();
serverControl.start(new PrintWriter(System.out, true));
} catch (Exception e) {
e.printStackTrace();
}
For connection i wrote this code
public static Connection getderbyConnection() throws ClassNotFoundException, SQLException
{
String url = "jdbc:derby://localhost:1527/XLS_Uniquewordlist;create=true";
String user = "root";
String password = "mantra";
Class.forName("org.apache.derby.jdbc.ClientDriver");
return (Connection) DriverManager.getConnection(url, user, password);
}
I am getting this exception
Exception in thread "DRDAConnThread_2" java.lang.NoSuchMethodError:
org.apache.derby.iapi.jdbc.EnginePreparedStatement.getVersionCounter()J
at org.apache.derby.impl.drda.DRDAStatement.prepare(Unknown Source)
at org.apache.derby.impl.drda.DRDAStatement.explicitPrepare(Unknown
Source)
at org.apache.derby.impl.drda.DRDAConnThread.parsePRPSQLSTT(Unknown
Source)
at org.apache.derby.impl.drda.DRDAConnThread.processCommands(Unknown
Source)
at org.apache.derby.impl.drda.DRDAConnThread.run(Unknown Source)
May 12, 2015 5:17:59 PM xls_parser.Main_panel btnokActionPerformed
SEVERE: null
java.sql.SQLSyntaxErrorException: DERBY SQL error: SQLCODE: -20001, SQLSTATE: 42X05, SQLERRMC: APP.UNIQUEWORDLIST42X05
at org.apache.derby.client.am.SQLExceptionFactory40.getSQLException(Unknown
Source)
at org.apache.derby.client.am.SqlException.getSQLException(Unknown
Source)
at org.apache.derby.client.am.Connection.prepareStatement(Unknown Source)
I installed MySQL database & JDBC. I created a database called feedback through MySQL command line client, and I want to access that database through a java program.
Here is the commands I used on MySQL command line client create the database.
create database feedback;
use feedback;
CREATE USER sqluser IDENTIFIED BY 'sqluserpw';
grant usage on *.* to sqluser#localhost identified by 'sqluserpw';
grant all privileges on feedback.* to sqluser#localhost;
CREATE TABLE COMMENTS (id INT NOT NULL AUTO_INCREMENT,
MYUSER VARCHAR(30) NOT NULL);
INSERT INTO COMMENTS values (default, 'lars');
Then, the code in Java:
package de.vogella.mysql.first;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Date;
import javax.swing.JOptionPane;
public class MYSQLACCESS {
private Connection connect = null;
private Statement statement = null;
private PreparedStatement preparedStatement = null;
private ResultSet resultSet = null;
public void readDataBase() throws Exception {
JOptionPane.showMessageDialog(null, "Before try" );
try {
// This will load the MySQL driver, each DB has its own driver
Class.forName("com.mysql.jdbc.Driver");
// Setup the connection with the DB
JOptionPane.showMessageDialog(null, "1" );
connect = DriverManager.getConnection("jdbc:mysql://localhost/feedback?"
+ "user=sqluser&password=sqluserpw");
// Statements allow to issue SQL queries to the database
statement = connect.createStatement();
// Result set get the result of the SQL query
resultSet = statement.executeQuery("select * from FEEDBACK.COMMENTS");
// writeResultSet(resultSet);
String my_user = resultSet.getString("MYUSER");
System.out.println(my_user);
JOptionPane.showMessageDialog(null, my_user );
} catch (Exception e) {
throw e;
}
}
}
The Main Class:
package de.vogella.mysql.first;
import de.vogella.mysql.first.MYSQLACCESS;
public class Main {
public static void main(String[] args) throws Exception {
MYSQLACCESS first_access = new MYSQLACCESS();
first_access.readDataBase();
}
}
However, I get the following exception:
Exception in thread "main" com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException:
Access denied for user 'sqluser'#'localhost' to database 'feedback'
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.Util.getInstance(Util.java:386)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1054)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4237)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4169)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:928)
at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1750)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1290)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2493)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2526)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2311)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:834)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:416)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:347)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at de.vogella.mysql.first.MYSQLACCESS.readDataBase(MYSQLACCESS.java:30)
at de.vogella.mysql.first.Main.main(Main.java:7)
I am following the tutorial in the following link
Any help?
The user sqluser does not have the privileges to access database feedback on the localhost.
Use the mysql command line tool and grant the privileges to the user.
Do not forget to flush privileges
usually when having this exception:
Access denied for user 'sqluser'#'localhost' to database 'feedback'
means that this user don't have enough privileges to access the Database, what I would suggest you to do is to go to your SQL shell and write this command:
show grants;
it would show you which users has access to the Database and with their level of privilege
if this user don't seem to have the necessary privilege to access the DB you can grant it to him by writing this query in your SQL Shell
GRANT ALL PRIVILEGES ON *.* TO 'sqluser'#'localhost' WITH GRANT OPTION;
Good Luck;
Here is my code:
package dsnless;
import java.sql.*;
////////////////////////////////////////////////////////////
//This class will be used to fire queries to the database
////////////////////////////////////////////////////////////
public class Query {
public Query(){
String pathToDatabase = "E:/Eclipse Projects/JDBC/src/datasouce/School.mdb";
String database = "jdbc:odbc:Driver="+
"{Microsoft Access Driver(*.mdb,*.accdb)};" +
":DBQ=" + pathToDatabase;
try{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
con = DriverManager.getConnection(database);
}catch(Exception e){
e.printStackTrace();
}
}
public static void main(String[] args) {
new Query();
}
Connection con;
Statement s;
ResultSet r;
}//class Query end
Here is the exception:
java.sql.SQLException: [Microsoft][ODBC Driver Manager] DRIVER keyword syntax error
at sun.jdbc.odbc.JdbcOdbc.createSQLException(Unknown Source)
at sun.jdbc.odbc.JdbcOdbc.standardError(Unknown Source)
at sun.jdbc.odbc.JdbcOdbc.SQLDriverConnect(Unknown Source)
at sun.jdbc.odbc.JdbcOdbcConnection.initialize(Unknown Source)
at sun.jdbc.odbc.JdbcOdbcDriver.connect(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at dsnless.Query.<init>(Query.java:14)
at dsnless.Query.main(Query.java:20)
And there is a new exception, too:
[Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified
at sun.jdbc.odbc.JdbcOdbc.createSQLException(Unknown Source)
at sun.jdbc.odbc.JdbcOdbc.standardError(Unknown Source)
at sun.jdbc.odbc.JdbcOdbc.SQLDriverConnect(Unknown Source)
at sun.jdbc.odbc.JdbcOdbcConnection.initialize(Unknown Source)
at sun.jdbc.odbc.JdbcOdbcDriver.connect(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at dsnless.Query.<init>(Query.java:14)
at dsnless.Query.main(Query.java:20)
Question
Please tell me what is wrong. I suspect it is the String database but stil it is only a guess.
Nailed it, myself
I changed the extensions supported from (*.mdb,*.accdb) to only (*.mdb) and it worked. Any idea as to why that happened???
You have an additional colon here, remove it
String database = "jdbc:odbc:Driver="+
"{Microsoft Access Driver(*.mdb,*.accdb)};" +
":DBQ=" + pathToDatabase;
^
I'm new to GWT. I'm trying to connect my Oracle10g database to GWT server program,
I'm using this code:
public class Database_connect
{
public static void connect()
{
System.out.println("This is a test project");
Connection con=null;
try
{
Class.forName("oracle.jdbc.OracleDriver");
System.out.println("Oracle JDBC driver loaded ok.");
con=DriverManager.getConnection("jdbc:oracle:thin:#127.0.0.1:1521:XE","naren", "naren");
System.out.println("Connected with #localhost:1521:XE.");
System.out.println("We have done it successfully");
}
catch(Exception e)
{
System.out.println(e);
}
}
}
in server file i'm calling the connect() function
public class GreetingServiceImpl extends RemoteServiceServlet implements GreetingService
{
public String greetServer(String input) throws IllegalArgumentException
{
Database_connect.connect();
}
}
but it's showing error.
I don't know what to do now. Anyone help me. Thanks for advance.
the error is
[WARN] failed Server#6e058516
java.net.BindException: Address already in use: bind
at sun.nio.ch.Net.bind0(Native Method)
at sun.nio.ch.Net.bind(Unknown Source)
at sun.nio.ch.Net.bind(Unknown Source)
at sun.nio.ch.ServerSocketChannelImpl.bind(Unknown Source)
at sun.nio.ch.ServerSocketAdaptor.bind(Unknown Source)
at org.mortbay.jetty.nio.SelectChannelConnector.open(SelectChannelConnector.java:205)
at org.mortbay.jetty.nio.SelectChannelConnector.doStart(SelectChannelConnector.java:304)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
at org.mortbay.jetty.Server.doStart(Server.java:233)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672)
at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1093)
at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:836)
at com.google.gwt.dev.DevMode.main(DevMode.java:311)
[ERROR] shell failed in doStartupServer method
You are running the project 2 times i think ..please kill all the java processes in task manager and run the project only once ..