Servlets & connection

We develop servlets and creation of connection was replaced in init() method. But if many people work at the same time
then Excpetion "not streaming mode" was generated.
public class viewReport extends HttpServlet
Connection conn;
public void init(ServletConfig config) throws ServletException
try
{super.init(config);
Class.forName (oracle.jdbc.driver.OracleDriver);
conn = DriverManager.getConnection (jdbc:oracle:thin:@Uran:1521:ORCL,
"scott", "tiger");
conn.setAutoCommit(false);
catch(Exception err)
If we remove
conn = DriverManager.getConnection (jdbc:oracle:thin:@Uran:1521:ORCL,
"scott", "tiger");
in the doGet() and doPost() methods nothing exception was trown.
Therefore it is necessary that One request = One connection. Is it true?
On the site Sun I read that we can create connection in the init() method. But this is not true in fact.
Thank you
null

"...I thought it would be easier if I just used a connectionpool.java file that i got from a book..."
I guess you'll find out. Depends on how good the book is, I guess.
.class files for Web apps always go in the WEB-INF/classes directory, of course. If they have a package statement, which they must for Tomcat, the package directory structure must be reproduced under WEB-INF/classes.
That's runtime. Compiling is different. The error is telling you that you didn't put that class in the CLASSPATH when you compiled:
http://java.sun.com/j2se/1.4.2/docs/tooldocs/windows/classpath.html
MOD

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Hi,
I tried almost all the midlets servlet connection examples on various tutorial sites including sun's, they all run perfectly fine on J2ME wireless toolkit emulator but when I download them on Seimens SL45i with WAP connection , J2ME compliant and on O2 XDA pda with GPRS and CrEme virtual java machine and me4se library for MIDlet support its not working. If I connect PDA with PC using MS active sync, the MIDLet is able to connect with servlet or normal web page and retrive data from that perfectly, but when I remove the pda from docking station and run MIDlet, its not able to connect with servlet. Is there something more you have to do to access GPRS or WAP feauture of PDA/mobile phone.
I am using normal HttpConnection to connect with the servlet.
Thanks in advance
Dhiraj

I'm playing with some sockets.
can you please help me?!
J2ME uses only HTTP connections?
and what are the sockets? what is the difference between CLDC socket and J2SE Socket?
is there any other way to communicate with a Servlet?
and very important..
is there a difference if it's using GPRS or 3G?
would the http connection work for all? and just the connection speed would change?
help me!!

Exmpl of Servlet connect with ORacle

Hi folks,
Can anyone send me example of Java Servlet connectivity with Oracle.
i m not able to connect servlet with oracle.
u guys can reply me on [email protected]
thanks
dal hit

No.
The code for connecting to Oracle from a Servlet is no different from connecting to Oracle from any other Java application. So tell you what, you show us what you've tried and the error message(s) and we'll help you debug it.
99.999% of the time it's a failure to put the driver Jar file into the classpath, the specifics of which vary from application server to application server. Which one are you using?
u guys can reply me on [email protected]
We can, but we won't. This is not your personal bugfixing service. Pay if you want that kind of help. If you want it for free, do it through the forums or go away.
Probably you'll never read this response, but that's your problem not mine.

Servlet connection to mssql

i want to connect servlet to mssql database on server.....i hv already created database from mssql server 2005....i hv written code for servlet.....but i dint getting wht should i write in Class.forname(); wht will be the URl also.....i hv sqljdbc.jar....how to do connection with database...

try
java.lang.Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
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ex.printStackTrace();
}

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When i try to connect my servlet with oracle it didnt detect oracle driver. My Simple java class was connect successfully but when i move to servlet i didnt work. Classnotfoundexception Occur tell me what i do and where i place classes12.zip folder in tomcat server.
Thank You
Regards
Uzair

Rename the classes12.zip to be classes12.jar
Tomcat only reads jar files, not zip files.
It should be in one of the following (in my order of preference):
- web-inf/lib
- TOMCAT/shared/lib
- TOMCAT/common/lib
Cheers,
evnafets

ORA-12519 with servlet connect

Hi,
I'm facing a strange behaviour on my tomcat webserver with a servlet. I'm using Oracle 10g as the database and try to access it with my servlet.
The doPost-method throws the following exception while trying to establish the connection to the RDBMS:
"SQLException:
Connecting not possible:
Listener refused the connection with the following error:
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After starting my servlet, the connection to the database for other applications blocks with the same error message
for a few minutes. After these few minutes connecting to the database is possible again!!! Restarting the database and the listener also helps...
public void doPost( HttpServletRequest request, HttpServletResponse response ) throws IOException, ServletException {
Connection conn = null;
response.setContentType( "text/html" );
PrintWriter out = response.getWriter();
String connStr = "jdbc:oracle:thin:@localhost:1521:DBTEN";
try{
Class.forName("oracle.jdbc.driver.OracleDriver");
}catch( ClassNotFoundException cnf ){
out.println( "CNFException: "+cnf.getMessage() );
//retrieve Connection
try{
conn = DriverManager.getConnection( connStr, "scott", "tiger" );
}catch( SQLException sqle ){
out.println( "SQLException: Connecting not possible: "+sqle.getMessage()+" " );
When I put that part in a 'normal' main program everything is ok. I can connect to the database and access tables with select statements and everything is ok.
public static void main(String[] args) {
Connection conn = null;
//retrieve Connection
try{
String connStr = "jdbc:oracle:thin:@localhost:1521:DBTEN";
try{
Class.forName("oracle.jdbc.driver.OracleDriver");
}catch(ClassNotFoundException cnf){
System.out.println( "CNFException: "+cnf.getMessage() );
conn = DriverManager.getConnection( connStr, "scott", "tiger" );
}catch( SQLException sqle ){
System.out.println( "SQLException:"+sqle.getMessage() );
Does anyone have an idea what the problem is in this case?
Regards,
Lars

"Note: The use of the DriverManager class to establish a connection to a database is deprecated." --
http://download-uk.oracle.com/docs/cd/B25329_01/doc/appdev.102/b25320/getconn.htm
To open a connection use something like this:
OracleDataSource ods = new OracleDataSource();
ods.setUser("username");
ods.setPassword("password");
ods.setURL("jdbc:oracle:thin:@localhost:1521:XE");
ods.getConnection();
Instead of this:
Class.forName("oracle.jdbc.OracleDriver");
DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:XE", "username", "password");

JDBC/Servlets Connectivity Problems.

Hi,
I'm new to Java development.
I'm trying to run this simple Servlet on
OS : Sun Solaris 2.6
Web Server : Netscape Enterprise Server
Database : Oracle 8i
JDK2 and JSDK2 installed on the Server.
JDBC Driver : Native Oracle JDBC Driver
This program works perfect on the Server if I run it as a program (Not a Servlet). However when running it as a Servlet, JUST DOESN't do ANYTHING. Doesn't return any error nor does execute the SQL Command.
Also how can I enable tracing to Trap errors generated on the Server by the Servlet.
Thanks for all your help....
Here's the Pogram:
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import java.sql.*;
import oracle.jdbc.driver.*;
public class CreateTable1 extends HttpServlet {
public void init(ServletConfig config)
throws ServletException {
super.init(config);
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
ServletOutputStream out = response.getOutputStream();
out.println("<html>");
out.println("<head><title>CR2Reat Table Server</title></head>");
out.println("<body>");
out.println(" Before Create...");
try {
DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
Connection con = DriverManager.getConnection("jdbc:oracle:kprb:@oracle","uername","password");
Statement statement = con.createStatement();
statement.executeUpdate("CREATE TABLE kj_newCont1" +
"(title_id NUMBER, title_name VARCHAR2(50)," +
"rating CHAR(5), price NUMBER(7,2), quantity NUMBER," +
"type_id INTEGER, category_id INTEGER)");
catch (SQLException sqle) {
System.err.println(sqle.getMessage());
catch (Exception e) {
System.err.println(e.getMessage());
out.println(" AfterClose");
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out.close();
public String getServletInfo() {
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null

To run servlets you must have a special server to run them like JRun or Java Web Server visit www.allaire.com to download JRun
You must also download the servlet.jar
java.sun.com
you must configure your CLASSPATH too
CLASSPATH=".:<path>classes12_01.zip":".:<path>servelet.jar"
I'm using Red Hat Linux 6.2 I think this can Help you

Servlet connection refused: connect

here my problem can any one help
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     at com.evermind.server.http.HttpRequestHandler.run(HttpRequestHandler.java:119)
     at com.evermind.server.http.HttpRequestHandler.run(HttpRequestHandler.java:112)
     at oracle.oc4j.network.ServerSocketReadHandler$SafeRunnable.run(ServerSocketReadHandler.java:260)
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I am using Jdeveloper 10.1.3.0.4

Servlet connecting to MS SQL

Hi guys....... i am having problems connecting to MS SQL server. I think this may be due to the configuration of the USERID and PASSWORD during the ODBC setting, but after much meddling, it still didnt work. Below is e code i used.
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import com.internetcds.jdbc.tds.*;
public class sample extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws IOException, ServletException
try {
System.out.println("Before Class " );
PrintWriter out=null;
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System.out.println("Before Connection " );
java.sql.Connection Conn = (java.sql.Connection)java.sql.DriverManager.getConnection("jdbc:freetds:sqlserver:SQLServer","sa","password");
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java.sql.ResultSet rs = st.executeQuery();
while(rs.next()) {
System.out.println(rs.getString(1));
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i haven got any error compiling
but it dun seem to be able to read this line
java.sql.DriverManager.getConnection("jdbc:freetds:sqlserver:SQLServer","sa","password");
I dun think i downloaded any driver, but i did download the .jar file for it though
Experts Please advice........ thanx

IMHO you don't have to import the com.internetcds.jdbc.tds.* because you import it via
Class.forName("com.internetcds.jdbc.tds.Driver");.
Please print the stacktrace.
Use
} catch(Exception e) {
e.printStackTrace()
}instead
} catch(Exception e) {
e.printStackTrace()
}and post the error message.
Be sure that the lib from com.internetcds is in a directory from your webserver where it is loaded.
Dietmar

Applet Servlet Connection

Hi,
I am trying to develop a chatroom application. I am using a applet as client which communicates with a servlet by recieving and sending a serialized object.
This is done by using the URLConnection class.
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Thanks

Maybe you should open a socket connection from the applet to the servlet instead of using URLConnection. There is a tutorial on sockets on the java.sun.com site.

Applet to servlet connection failed using plugin 1.3

Hi,
I tried to send a serialized object from an Applet to a Servlet. It worked well until I installed the Java plugin version 1.3.
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here is my code example:
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since the Apache server is listening on port 80 I thought it is not necessary to use the port number. I tried now with the new URL:
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Problem with servlet connection

Hi guys,
Im gettin an nullpointer exception when connect to a servlet. Some "abstract" code:
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servletConnection.setUseCaches(false);
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usereceivedvalues();
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Some ideas ? Thankss.

I think your problem is in servlet. You can try the servlet without midlet in a IExplorer browser.
ps1=con.prepareStatement("SELECT * FROM userLogin where uID=?");
ps1.setString(1,uID);
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Servlet -- Connection

Hello to all, I',m presently working on an application involving servlets and odbc driver which is on a TomCat enviroment. I have 18 servlets that are called depending on what is needed to do, as for the connection, there is only one made .. once the user logs in. For the rest of the connection, I'm reusing the method from MyLogin.java (servlet) ...... ....
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This process works fine for one user, but when there are 2 or more on line ..... I'm getting error messages!!
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It seems to me that your problem may be solved by using threads... but I'm no expert.

Problem create servlet connecting mysql

Hello,
I'm trying to create a servlet with JBuilder foundation.
I've a java file, not included in the package of the JBuilder project and i want to deploi it on the Tomcat server (version 5.0). I 'Make' it and i deploy the .class.
When i execute it I've the following driver error :
java.sql.SQLException: No suitable driver
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Thank you........
My code:
import java.io.*;
import java.util.*;
import java.net.*;
import sun.beans.editors.IntEditor;
import net.homeip.trv.util.*;
import com.mysql.jdbc.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import com.mysql.jdbc.Statement;
import com.mysql.jdbc.ResultSet;
import java.util.Locale;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import javax.servlet.*;
import javax.servlet.http.*;
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public void doGet(HttpServletRequest request,
HttpServletResponse response) throws IOException, ServletException
response.setContentType("text/html");
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//-------------------------------start MySQL connection-----------------------------
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String password = "root";
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catch (ClassNotFoundException ex2)
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I've to deploy it in the same place of .class ?No, you should create a war (or ear) file, and place the driver jar in the correct location of that file.
http://java.sun.com/j2ee/tutorial/1_3-fcs/doc/WebComponents3.html
Kaj

Rtp servlet connection

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desktop. Generally we use servlet request in order to start a servlet for processing.
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waynres wrote:
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