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Applet Servlet SQL Problem

I have set up an applet servlet communication link, when i call the doPost() method i wish to recieve the data sent by the applet a Java Object, namely Job. I can recieve the job without any problems in the servlet, i want to then store that job in my SQL db, for which i have created a separate class namely DataStore. Which has the ability to store and update data in my db. When i test the db using in a separate class as:

public static void main (String[] args){
DataStore ds = new DataStore();
ds.connect();
Job aJob = new Job(1, "today", "bye");
ds.addJobEntry(aJob);
}

This works fine. HOWEVER, when i invoke the same operation in my servlet using:

      public void doPost(
            HttpServletRequest request,
            HttpServletResponse response)
            throws ServletException, IOException {
            try {
                  response.setContentType("application/x-java-serialized-object");
                  InputStream in = request.getInputStream();
                  ObjectInputStream inputFromApplet = new ObjectInputStream(in);
                  Job newJob = (Job) inputFromApplet.readObject();
inputFromApplet.close();

//add to database
ds = new DataStore();
ds.connect();
ds.addJobEntry(newJob);

            } catch (Exception e) {
                  e.printStackTrace();
            }
      }

It doesnt seem to add the entry to the database!!! PLEASE HELP

Any advice or help will be greatly appreciated

Regards.

ASKER

I think its somthing to do with my SQL driver, i am using Apache tomcat, where must i put the driver classes ?

>>
//add to database
ds = new DataStore();
ds.connect();
ds.addJobEntry(newJob);
>>

This looks wrong, you wouldn't want to create a new connection every time for optimal use, but if you're going to do that, you'll need to close it too

Check the references to those objects you're using by printing them and look in the log file

Put SQl driver in WEB-INF/lib directory, restart tomcat and see what happens
also can you check log file see if there's any error message dunmpped in?

ASKER

nope doesnt work if i do put the *.jar file in the lib folder

this is what im using:
Class.forName("com.mysql.jdbc.Driver");

Check for exceptions in your log file

ASKER

classNotFound

ASKER

i cant get the applet to locate the driver ive tried puttin it everywhere!!
if i put it in http://localhost:8080/JobApp/WEB-INF/lib

what would Class.forName("com.mysql.jdbc.Driver"); be?

Try putting it in

%CATALINA_HOME%\common\lib

too

ASKER

does that mean i have to change this Class.forName("com.sql.jdbc.Driver"); if i put it wer you just told me to put it? because it still doesnt work! i put
mysql-connector-java-3.1.8a-bin.jar in there this is driving me crazy!!

ASKER

this is what im getting!

network: Connecting http://localhost:8080/com/mysql/jdbc/Driver.class with proxy=DIRECT
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
      at sun.applet.AppletClassLoader.findClass(Unknown Source)
      at java.lang.ClassLoader.loadClass(Unknown Source)
      at sun.applet.AppletClassLoader.loadClass(Unknown Source)
      at java.lang.ClassLoader.loadClass(Unknown Source)
      at java.lang.ClassLoader.loadClassInternal(Unknown Source)
      at java.lang.Class.forName0(Native Method)
      at java.lang.Class.forName(Unknown Source)
      at JobApp.DataStore.connect(DataStore.java:25)
ETC......

Ah i see it's being loaded by your applet. In that case put the driver jar in the archive tag:

<applet code="XXX" archive="mysql-connector-java-3.1.8a-bin.jar" ... etc

Make sure it's with the applet in its package root

ASKER

ARGGGGHHH!!! Still not working!!!

this what i have done in ClientApplet.html

<HTML>
<HEAD>
<TITLE>Applet HTML Page</TITLE>
</HEAD>
<BODY>

<H3><HR WIDTH="100%">Job Client Applet<HR WIDTH="100%"></H3>

<P>
<APPLET codebase=.. code="JobApp/ClientApplet.class" archive="mysql-connector-java-3.1.8a-bin.jar" width=500 height=250></APPLET>
</P>

<HR WIDTH="100%"><FONT SIZE=-1><I>@author Rehan Uddin</I></FONT>
</BODY>
</HTML>

>><APPLET codebase=..

better

<APPLET codebase=".."

Do you mean that by the way?

>>code="JobApp/ClientApplet.class"

If that applet's in the package 'JobApp' it should be

code="JobApp.ClientApplet.class"

>>Do you mean that by the way?

As, if so, this:

>>archive="mysql-connector-java-3.1.8a-bin.jar"

should be

archive="../mysql-connector-java-3.1.8a-bin.jar"

ASKER

ive tried both approaches still nothing!! it still cannot locate the driver for the db

You'll have to get the paths right or it won't

ASKER

i have put everythin everywhere!! and still not working!! is it possible to send u my files so u can check wot i am doing wrong?

Not now sorry - it's 2 am here and i'm turning in!

>> i cant get the applet to locate the driver ive tried puttin it everywhere!!
Why does the applet need the driver?
Where does the exception come from Tomcat (your servlet container) or your Applet?
Also, can you make sure that your jar is not corupt?
do: jar tf mysql-connector-java-3.1.8a-bin.jar ( and search for an entry com/sql/jdbc/Driver.class)

ASKER

The driver class exits, sorry i mean i want to load the driver in the servlet when i do a get post so i can add a new entry to the sql database

If the applet is not making a direct connection to the db then it doesn't need the driver. If the driver is only used by the servlet, then putting it into WEB-INF/lib should be sufficient. From the previous stack trace it appeared that the applet was loading the driver

ASKER

ok i will try it

ASKER

where is the log file situated for tomcat?

ASKER CERTIFIED SOLUTION

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ASKER

this is what i get in catalina.... . txt file

04-May-2005 19:31:33 org.apache.coyote.http11.Http11Protocol init
INFO: Initializing Coyote HTTP/1.1 on http-8080
04-May-2005 19:31:33 org.apache.catalina.startup.Catalina load
INFO: Initialization processed in 1360 ms
04-May-2005 19:31:33 org.apache.catalina.core.StandardService start
INFO: Starting service Catalina
04-May-2005 19:31:33 org.apache.catalina.core.StandardEngine start
INFO: Starting Servlet Engine: Apache Tomcat/5.5.9
04-May-2005 19:31:33 org.apache.catalina.core.StandardHost start
INFO: XML validation disabled
04-May-2005 19:31:35 org.apache.coyote.http11.Http11Protocol start
INFO: Starting Coyote HTTP/1.1 on http-8080
04-May-2005 19:31:36 org.apache.jk.common.ChannelSocket init
INFO: JK: ajp13 listening on /0.0.0.0:8009
04-May-2005 19:31:36 org.apache.jk.server.JkMain start
INFO: Jk running ID=0 time=0/47 config=null
04-May-2005 19:31:36 org.apache.catalina.storeconfig.StoreLoader load
INFO: Find registry server-registry.xml at classpath resource
04-May-2005 19:31:36 org.apache.catalina.startup.Catalina start
INFO: Server startup in 3343 ms

and this is what im doing:
      public void doPost(
            HttpServletRequest request,
            HttpServletResponse response)
            throws ServletException, IOException {
            try {
                  response.setContentType("application/x-java-serialized-object");
                  InputStream in = request.getInputStream();
                  ObjectInputStream inputFromApplet = new ObjectInputStream(in);
                  Job newJob = (Job) inputFromApplet.readObject();
inputFromApplet.close();
try{
//add to database
ds = new DataStore();
ds.connect();
ds.addJobEntry(newJob);
}catch(Exception e){
e.printStackTrace();
}

            } catch (Exception e) {
                  e.printStackTrace();
            }
      }

the *.jar file is in the lib and everywhere i can think ov what am i doing wrong or not doing?

I assume you still get the class not found exception triggered from (new DataStore), right?
Can you post the code for it?
Did you try to configure/user Tomcat DS instead of loading the driver yourself -> see: http://jakarta.apache.org/tomcat/tomcat-5.5-doc/jndi-datasource-examples-howto.html

That looks like the wrong logfile. Try this:

System.err.println("SEARCHFORME");

then look for that String in the file system

ASKER

yes i tried that! this is my datastore code:

public class DataStore extends Thread{
private Connection conn;
/** Creates a new instance of DataStore */

public void connect(){
try {
// Step 1: Load the JDBC driver.
Class.forName("com.mysql.jdbc.Driver");

// Step 2: Establish the connection to the database.
String url = "jdbc:mysql://localhost:3306/jobdb";
conn = DriverManager.getConnection(url,"root","password");
Statement st = conn.createStatement();
} catch (Exception e) {
e.printStackTrace();
}

}
public void createTable(){

}

public void addJobEntry(Job addJob){
String insert = "INSERT INTO jobtable " + "VALUES (?)";
try {
PreparedStatement ps = conn.prepareStatement(insert);
ByteArrayOutputStream bout = new ByteArrayOutputStream();
ObjectOutputStream out = new ObjectOutputStream(bout);
out.writeObject(addJob);
byte[] bytes = bout.toByteArray();
ByteArrayInputStream in = new ByteArrayInputStream(bytes);
ps.setBinaryStream(1, in, bytes.length);
ps.executeUpdate();
} catch (Exception e) {
e.printStackTrace();
}
}

public ArrayList getJobList(){
ArrayList jobList = new ArrayList();
int i = 0;
String query = "SELECT Job FROM jobtable";
try{
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery(query);

while (rs.next()){
ByteArrayOutputStream out = new ByteArrayOutputStream();
InputStream in = rs.getBinaryStream(1);
int buf = -1;

while ((buf = in.read()) > -1) {
out.write(buf);
}

in.close();
ObjectInputStream ois = new ObjectInputStream(new ByteArrayInputStream(out.toByteArray()));
Object retrievedObject = ois.readObject();
Job recievedJob = (Job) retrievedObject;
jobList.add(i, recievedJob);
i++;
}
} catch (Exception e) {
e.printStackTrace();
}
return jobList;
}

public void updateJob(Job oldJob, Job newJob){
String query = "SELECT * FROM jobtable";
try{
Statement stmt = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
ResultSet rs = stmt.executeQuery(query);

while (rs.next()){
ByteArrayOutputStream out = new ByteArrayOutputStream();
InputStream in = rs.getBinaryStream(1);
int buf = -1;

while ((buf = in.read()) > -1) {
out.write(buf);
}

in.close();
ObjectInputStream ois = new ObjectInputStream(new ByteArrayInputStream(out.toByteArray()));
Object retrievedObject = ois.readObject();
Job recievedJob = (Job) retrievedObject;
if ((recievedJob.getJobNumber()) == (oldJob.getJobNumber())){
rs.deleteRow();
addJobEntry(newJob);
}
}
} catch (Exception e) {
e.printStackTrace();
}
}

ASKER

does this mean anything?

http://archives.postgresql.org/pgsql-interfaces/1999-05/msg00181.php

>> yes i tried that!

An the result was ...?

Did you try adding the jar to your war WEB-INF/lib?
Did you check if the jar is not corrupted?
Did you try using the Tomcat DS aproach instead?

ASKER

>>Did you try adding the jar to your war WEB-INF/lib?
yes
>>Did you check if the jar is not corrupted?
yes downloaded fresh copy n checked and Driver does exist

>>Did you try using the Tomcat DS aproach instead?
Yes dont knw if what i did is correct this is my server.xml file

<Context path="/JobApp" docBase="JobApp" ************** have i got this correct? the name of my folder is JobApp and the name ov my package is JobApp
debug="5" reloadable="true" crossContext="true">

<Logger className="org.apache.catalina.logger.FileLogger"
prefix="localhost_DBTest_log." suffix=".txt"
timestamp="true"/>

<Resource name="jdbc/JobApp"
auth="Container"
type="javax.sql.DataSource"/>

<ResourceParams name="jdbc/JobApp">
<parameter>
<name>factory</name>
<value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
</parameter>


<parameter>
<name>maxActive</name>
<value>100</value>
</parameter>


<parameter>
<name>maxIdle</name>
<value>30</value>
</parameter>


<parameter>
<name>maxWait</name>
<value>10000</value>
</parameter>


<parameter>
<name>username</name>
<value>root</value>
</parameter>
<parameter>
<name>password</name>
<value>password</value>
</parameter>


<parameter>
<name>driverClassName</name>
<value>com.mysql.jdbc.Driver</value>
</parameter>


<parameter>
<name>url</name>
<value>jdbc:mysql://localhost:3306/jobdb?autoReconnect=true</value>
</parameter>
</ResourceParams>
</Context>

</Host>

</Engine>

</Service>

</Server>

<Context path="/JobApp" docBase="JobApp" ************** have i got this correct? the name of my folder is JobApp and the name ov my package is JobApp
debug="5" reloadable="true" crossContext="true">

docBase="/JobApp" -> this should be the full path to your web application.
path="/JobApp" -> this is the web application context name: probably should be path="JobApp"
see: http://jakarta.apache.org/tomcat/tomcat-5.5-doc/config/context.html

Before you go any further, i'd get your logging organised, or you're not going to be able to diagnose anything...

ASKER

where is my log? where should i b looking?

>> where is my log?

That's the point - you need to find out. If it's configured you should be able to search the file system to find it. If it isn't you need to configure it. See your Tomcat docs

:-)