Develop Reference

Java - sqlite db file cannot be found

Comment on the edit: I think I had already fixed my original issue (driver could not be found) and now I have the following problem:
EDIT 2: when I replace the url in context.xml with the full path (url=jdbc:sqlite:C:/Dev/workspace/jerseyrestdemo/resources/greetings.sqlite) it works. How can I now make that path relative??
EDIT 3: I followed the instructions inhow to configure JNDI datasource for db connection in tomcat: 1. Delete my project-specific context.xml and put the content into tomcat7/conf/context.xml. There I specified the namespace name=jdbc/greetings.sqlite
<Resource name="jdbc/greetings.sqlite"
auth="Container"
type="javax.sql.DataSource"
maxActive="100"
maxIdle="30"
maxWait="10000"
driverClassName="org.sqlite.JDBC"
url="jdbc:sqlite:resources/greetings.sqlite"
factory="org.apache.tomcat.dbcp.dbcp.BasicDataSourceFactory">
</Resource>
In the DAO class I get the connection via
Context initCtx = new InitialContext();
Context envCtx = (Context) initCtx.lookup("java:comp/env");
DataSource ds = (DataSource) envCtx.lookup("jdbc/greetings.sqlite");
conn = ds.getConnection();
But I still get the error org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (path to 'resources/greetings.sqlite': 'C:\Dev\eclipse\resources' does not exist)
EDIT 4: In the end, I go for storing the db file in the catalina home
/${catalina.home}/databases/greetings.sqlite as explained here. I guess you shouldn't store your db files in the web app project anyways
I have a SQLite db file in resources/greetings.sqlite under my project folder but when I run my webapp on tomcat it cannot find the db file:
java.sql.SQLException: path to 'resources/greetings.sqlite': 'C:\Dev\eclipse\resources' does not exist
at org.sqlite.core.CoreConnection.open(CoreConnection.java:192)
at org.sqlite.core.CoreConnection.<init>(CoreConnection.java:76)
at org.sqlite.jdbc3.JDBC3Connection.<init>(JDBC3Connection.java:25)
at org.sqlite.jdbc4.JDBC4Connection.<init>(JDBC4Connection.java:24)
at org.sqlite.SQLiteConnection.<init>(SQLiteConnection.java:45)
at org.sqlite.JDBC.createConnection(JDBC.java:114)
at org.sqlite.JDBC.connect(JDBC.java:88)
at java.sql.DriverManager.getConnection(DriverManager.java:664)
at java.sql.DriverManager.getConnection(DriverManager.java:270)
at demo.rest.jersey.spring.dao.JdbcGreetingDAO.getRowCount(JdbcGreetingDAO.java:29)
at demo.rest.jersey.spring.GreetingService.randomGreeting(GreetingService.java:29)
at demo.rest.jersey.spring.GreetingService.greet(GreetingService.java:18)
at demo.rest.jersey.spring.SpringRequestResource.getHello(SpringRequestResource.java:28)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
I have copied the jdbc jar into the tomcat/lib directory and added the code below in META-INF/context.xml and WEB-INF/web.xml.
This is what I put into my web.xml
<resource-ref>
<description>Greetings Database</description>
<res-ref-name>jdbc/greetings.sqlite</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
and I have created a file in WebContent/META-INF/context.xml. I assume the relative path in the url field of the Resource is not how it should be.
<?xml version="1.0" encoding="UTF-8"?>
<Context>
<Resource name="jdbc/greetings.sqlite"
auth="Container"
type="javax.sql.DataSource"
driverClassName="org.sqlite.JDBC"
url="jdbc:sqlite:resources/greetings.sqlite"
factory="org.apache.tomcat.dbcp.dbcp.BasicDataSourceFactory">
</Resource>
</Context>
What I would like to avoid is putting the db file in a tomcat subdir but just make it part of the project, so others don't have to bother moving the file to their tomcat dir.
Here is the DAO class
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class JdbcGreetingDAO implements GreetingDAO
{
private Connection getConn() throws SQLException
{
Connection conn = null;
try
{
Context ctx = new InitialContext();
DataSource ds = (DataSource)ctx.lookup("java:comp/env/jdbc/greetings.sqlite");
conn = ds.getConnection();
}
catch(NamingException ne)
{
System.out.println("Cannot get connection");
ne.printStackTrace();
}
return conn;
}
#Override
public void insert(String greeting) throws SQLException
{
Connection conn = getConn();
Statement st = conn.createStatement();
st.executeUpdate(String.format("INSERT INTO greetings (greeting) VALUES (%s)", greeting));
}
}
The DAO is used by a GreetingsService
public class GreetingService
{
#Autowired
private JdbcGreetingDAO dataSource;
public String addGreeting(String greeting) throws SQLException
{
dataSource.insert(greeting);
return greeting;
}
}
Thanks for the help

javax.naming.NameNotFoundException: Name [jdbc/FsEDBUser] is not bound in this Context

I've set up JNDI resources before, but I'm coming across an issue I'm not sure how to correct on my apache-tomcat-8.0.36 server.
My context.xml file contains the following:
<ResourceLink name="jdbc/FsEDBAdmin" global="jdbc/FsEDBAdmin" type="javax.sql.DataSource" />
<ResourceLink name="jdbc/FsEDBUser" global="jdbc/FsEDBUser" type="javax.sql.DataSource" />
<Resource name="jdbc/FsEDBAdmin" auth="Container"
type="javax.sql.DataSource" driverClassName="org.postgresql.Driver"
url="jdbc:postgresql://location"
username="user_admin" password="pass"
maxActive="20" maxIdle="10" maxWait="-1"/>
<Resource name="jdbc/FsEDBUser" auth="Container"
type="javax.sql.DataSource" driverClassName="org.postgresql.Driver"
url="jdbc:postgresql://location"
username="user_user" password="pass"
maxActive="20" maxIdle="10" maxWait="-1"/>
My web.xml :
<resource-ref>
<description>Admin Connection</description>
<res-ref-name>jdbc/FsEDBAdmin</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
<resource-ref>
<description>User Connection</description>
<res-ref-name>jdbc/FsEDBUser</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
I'm also using these connections to define a Realm for authentication:
server.xml:
<Realm className="org.apache.catalina.realm.LockOutRealm">
<!-- This Realm uses the UserDatabase configured in the global JNDI
resources under the key "UserDatabase". Any edits
that are performed against this UserDatabase are immediately
available for use by the Realm. -->
<Realm className="org.apache.catalina.realm.UserDatabaseRealm"
resourceName="UserDatabase"/>
<Realm className="org.apache.catalina.realm.DataSourceRealm"
digest="digest_method" dataSourceName="jdbc/FsEDBAdmin" userTable="schema.table_name"
userNameCol="name_col" userCredCol="pass_col"
userRoleTable="schema.table_name" roleNameCol="rolename_col"
localDataSource="true"/>
</Realm>
But when I launch my application I'm getting the error mentioned in the title. I can give a full stack trace if requested.
I'd like to add on, that this was working at one point and the most recent change was the use of the Realm for authentication. Obviously I've made a mistake in defining these resources in one location or another, so another set of eyes to tell me where would be greatly appreciated. Thank you.
EDIT: This is how I'm calling the resource:
import path.to.CommonTools;
import java.sql.Connection;
import java.sql.SQLException;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import org.apache.tomcat.dbcp.dbcp2.BasicDataSource;
/**
*
* #author Michael Potts
*/
public enum Resource {
INSTANCE;
private static BasicDataSource basicAdmin = null;
private static BasicDataSource basicUser = null;
private static final String JNDI_PREFIX = "java:/comp/env";
private static final String ADMIN_DB_NAME = "jdbc/FsEDBAdmin";
private static final String USER_DB_NAME = "jdbc/FsEDBUser";
/**
* Secure method that gives a connection from the pool for an Admin user
* #return java.sql.Connection
* #throws Exception Throws if Context isn't properly defined on Server
*/
public static Connection getAdminConnection() throws Exception {
try {
if(basicAdmin == null) { //1st time load
Context dbContext = (Context) new InitialContext().lookup(JNDI_PREFIX);
basicAdmin = (BasicDataSource) dbContext.lookup(ADMIN_DB_NAME);
}
return basicAdmin.getConnection();
} catch (NamingException | SQLException e) {
throw new RuntimeException("\nInvalid JNDI resource: " + ADMIN_DB_NAME + CommonTools.getStackTrace(e));
}
}
/**
* Secure method that gives a connection from the pool for a standard user
* #return java.sql.Connection
* #throws Exception Throws if Context isn't properly defined on Server
*/
public static Connection getUserConnection() throws Exception {
try {
if(basicUser == null) { //1st time load
Context dbContext = (Context) new InitialContext().lookup(JNDI_PREFIX);
basicUser = (BasicDataSource) dbContext.lookup(USER_DB_NAME);
}
return basicUser.getConnection();
} catch (NamingException | SQLException e) {
throw new RuntimeException("\nInvalid JNDI resource: " + USER_DB_NAME + CommonTools.getStackTrace(e));
}
}
}

So the solution for me was to remove ALL ENTRIES except the base Resource definitions in context.xml. This includes removing ResourceLink entries. So if you've tried everything and you're getting this error like I am just ignore all documentation and just define in Context.xml.

no suitable driver exception in connection pooling

I am trying to implement connection pooling using servlet. I know there are lots of similar questions has been asked but none is able to help.
Here is exception :
java.sql.SQLException: Cannot create JDBC driver of class for connect URL null at
org.apache.tomcat.dbcp.dbcp2.BasicDataSource.createConnectionFactory(BasicDataSource.java:2160)
at
org.apache.tomcat.dbcp.dbcp2.BasicDataSource.createDataSource(BasicDataSource.java:2032)
at
org.apache.tomcat.dbcp.dbcp2.BasicDataSource.getConnection(BasicDataSource.java:1532)
at
connection.CityInfoServlet.showCityInformation(CityInfoServlet.java:104)
at connection.CityInfoServlet.doGet(CityInfoServlet.java:76) at
javax.servlet.http.HttpServlet.service(HttpServlet.java:622) at
javax.servlet.http.HttpServlet.service(HttpServlet.java:729) at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
at
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
at
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
at
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:521)
at
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1096)
at
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:674)
at
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
at
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source) Caused by:
java.sql.SQLException: No suitable driver at
java.sql.DriverManager.getDriver(Unknown Source) at
org.apache.tomcat.dbcp.dbcp2.BasicDataSource.createConnectionFactory(BasicDataSource.java:2144)
... 27 more
I don't know why this exception show :
Caused by: java.sql.SQLException: No suitable driver.
I added jar file in WEB-INF/lib folder.
Here is my Servlet Code :
package connection;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.sql.DataSource;
#WebServlet("/CityInfoServlet")
public class CityInfoServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
DataSource dataSource = null;
public void init( ServletConfig config ) {
try{
Context initContext = new InitialContext();
Context envContext = (Context) initContext.lookup("java:/comp/env");
dataSource = (DataSource) envContext.lookup("jdbc/worldDB");
}
catch( Exception exe )
{
exe.printStackTrace();
}
}
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{
response.setContentType("text/html");
PrintWriter out = response.getWriter();
String title = "City Information From Mysql Database";
out.print("<html><body bgcolor=\"#f0f0f0\">");
out.print("<h1 align=\"center\">" + title + "</h1>\n");
showCityInformation(out);
out.print("</body></html>");
}
private void showCityInformation( PrintWriter out )
{
Connection connection = null;
PreparedStatement preparedStatement = null;
try {
String sql = "select * from city limit ?";
connection = dataSource.getConnection();
preparedStatement = connection.prepareStatement(sql);
preparedStatement.setInt(1, 10);
ResultSet rs = preparedStatement.executeQuery();
while( rs.next() )
{
int id = rs.getInt(1);
String name = rs.getString(2);
String countryCode = rs.getString(3);
String district = rs.getString(4);
int population = rs.getInt(5);
out.print("ID: " + id + "<br>");
out.print("Name: " + name+ "<br>");
out.print("CountryCode: " + countryCode+ "<br>");
out.print("District: " + district+ "<br>");
out.println("Population: " + population+ "<br>");
out.println("--------------------------------------"+ "<br>");
}
rs.close();
}
catch( Exception e )
{
e.printStackTrace();
}
finally
{
try {
if( preparedStatement != null ) {
preparedStatement.close();
}
}
catch( SQLException sqlException ){
sqlException.printStackTrace();
}
try
{
if( connection != null )
{
connection.close();
}
}
catch( SQLException sqlException )
{
sqlException.printStackTrace();
}
}
}
}
This is context.xml file
<?xml version="1.0" encoding="UTF-8"?>
<Context>
<Resource name="jdbc/worldDB" auth="Container" type="javax.sql.DataSource"
maxTotal="100" maxIdle="30" maxWaitMillis="10000"
username="root" password="12345" driverClassName="com.mysql.jdbc.Driver"
url="jdbc:mysql://localhost:3306/world"/>
</Context>

Cannot create JDBC driver of class for connect URL null
The URL for the connection isn't set, so the JDBC libraries can't determine what driver to load.

I think that..
1 - you have to copy suitable driver to Server/lib folder
2 - If you have to created DataSource Connection context.xml on your project META-INF then modify
3 - WEB.xml of you project like this (add this)
<resource-ref>
<description>MySQLDatasource</description>
<res-ref-name>jdbc/worldDB</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
Then you can run this app http://localhost:8080/app_name - ok
but if you want to call this app from http://localhost:8080
then you have to
1 - add Context tag to your Server/conf/server.xml file
2 - add this line to your Server/conf/context.xml
<Resource name="jdbc/worldDB" auth="Container" type="javax.sql.DataSource"
maxTotal="100" maxIdle="30" maxWaitMillis="10000"
username="root" password="12345" driverClassName="com.mysql.jdbc.Driver"
url="jdbc:mysql://localhost:3306/world"/>
3 - restart server
then it will find this connection from Server context.

NoInitialContextException Error Tomcat

I've been trying to find a solution here but I cant...
I have the following code and i get this error.
Am I missing something? Thank you :)
Code
package src;
import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.Wrapper;
import java.util.Hashtable;
import java.util.Properties;
import java.io.*;
import javax.*;
import javax.activation.DataSource;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import oracle.jdbc.pool.OracleDataSource;
public class TestServlet {
#SuppressWarnings("unused")
public static void main(String[] argv) throws SQLException, NamingException {
Context initialContext = new InitialContext();
if ( initialContext == null){System.out.println("initialContext null");}
else {System.out.println("initialContext");}
// Get DataSource
Context environmentContext = (Context)initialContext.lookup("java:/comp/env");
if ( environmentContext == null){System.out.println("envContext null.");}
else {System.out.println("envContext");}
DataSource ds = (DataSource)environmentContext.lookup("jdbc/testdb");
System.out.println("\n -------- Oracle JDBC Connection Testing ------");
try {
Connection jdbcConnection = ((Statement) ds).getConnection();
OracleDataSource ods = ((Wrapper) ds).unwrap(OracleDataSource.class);
jdbcConnection.close();
} catch (SQLException e) {
System.out.println("Connection Failed! Check output console");
e.printStackTrace();
return;
}
String message = "You are connected!";
System.out.println(message);
}
}
context.xml
<Context>
<Resource name="jdbc/testdb"
auth="Container"
type="javax.sql.DataSource"
maxActive="100"
maxIdle="30"
maxWait="10000"
username="dba01"
password="qvE-g7Cacontext.xml"
driverClassName="com.mysql.jdbc.Driver"
url="jdbc:oracle:thin:#10.0.1.6:1521:xe"/>
</Context>
Error
Exception in thread "main" javax.naming.NoInitialContextException: Need to specify class name in environment or system property, or as an applet parameter, or in an application resource file: java.naming.factory.initial
at javax.naming.spi.NamingManager.getInitialContext(Unknown Source)
at javax.naming.InitialContext.getDefaultInitCtx(Unknown Source)
at javax.naming.InitialContext.getURLOrDefaultInitCtx(Unknown Source)
at javax.naming.InitialContext.lookup(Unknown Source)
at src.TestServlet.main(TestServlet.java:34)
Please let me know if you need more information!

You need an initial context factory. For Tomcat it is org.apache.naming.java.javaURLContextFactory:
System.setProperty(Context.INITIAL_CONTEXT_FACTORY,
"org.apache.naming.java.javaURLContextFactory");

So is it the code deployed on the server? It seems you try to access the Context using standard java as you call static main (so I guess you are calling TeestServlet.main from your runtime). The context will be setup by the web server (Tomcat), so it is availble only after you deploy your web application to it.

Please note that driverClassName that you are using is incorrect.
It should be "oracle.jdbc.OracleDriver" if you are trying to connect to Oracle Database.
<Context>
<Resource name="jdbc/testdb"
auth="Container"
type="javax.sql.DataSource"
maxActive="100"
maxIdle="30"
maxWait="10000"
username="dba01"
password="qvE-g7Cacontext.xml"
driverClassName="com.mysql.jdbc.Driver"
url="jdbc:oracle:thin:#10.0.1.6:1521:xe"/>
</Context>

Access denied when attempting to connect to mysql from servlet in myeclipse

I'm trying to run a simple servlet/mysql webapp using tomcat server in my eclipse.
when I try to connect to the database from a servlet, I get the following error:
org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create
PoolableConnectionFactory (Access denied for user ''#'localhost' (using password: YES))
below is the script that I executed:
The servlet:
import java.io.IOException;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import javax.annotation.Resource;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.sql.DataSource;
public class EmployeeServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
#Resource(name = "jdbc/testDB")
DataSource ds;
public EmployeeServlet() {
super();
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
try {
Connection con = ds.getConnection();
Statement stmt = con.createStatement();
String query = "select * from Employee";
ResultSet rs = stmt.executeQuery(query);
PrintWriter out = response.getWriter();
response.setContentType("text/html");
out.print("<center><h1>Employee Details</h1></center>");
out.print("<html><body>");
out.print("<table border=\"1\" cellspacing=10 cellpadding=5>");
out.print("<tr><th>Employee ID</th>");
out.print("<th>Employee Name</th>");
out.print("<th>Salary</th>");
out.print("<th>Department</th></tr>");
while (rs.next()) {
out.print("<tr>");
out.print("<td>" + rs.getInt("emp_id") + "</td>");
out.print("<td>" + rs.getString("emp_name") + "</td>");
out.print("<td>" + rs.getDouble("salary") + "</td>");
out.print("<td>" + rs.getString("dept_name") + "</td>");
out.print("</tr>");
}
out.print("</table></body></html>");
} catch (SQLException e) {
e.printStackTrace();
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
}
}
content of context.xml file:
<?xml version="1.0" encoding="UTF-8"?>
<Context crossContext="true">
<WatchedResource>WEB-INF/web.xml</WatchedResource>
<Resource name="jdbc/testDB" auth="Container"
type="javax.sql.DataSource"
maxActive="100" maxIdle="30" maxWait="10000"
username="root" password="root"
driverClassName="com.mysql.jdbc.Driver"
url="jdbc:mysql://localhost/mysql">
</Context>

try connecting to mysql from any other tool / from command prompt with all the information you used in your code to connect to the same. Try including the port also in the connection url. Default port is 3306

Use mysql's GRANT query to give you permissions to access the database if you are accessing db from remote client.

seems port number missing in the url:
jdbc:mysql://localhost:<port>/mysql