Thread: Error:java.lang.ClassNotFoundException: org.postgresql.Driver

    IMVHO, I completely got rid of issues like this when I started using Maven (or Gradle or equivalent).

    I'd recommend you to do the same (and by the way, use a more modern version of the driver).

   
    Álvaro

-- 
Álvaro Hernández Tortosa


-----------
8Kdata

Hi All,

I am working on java project to insert and fetch data from postgresql database. While using jbdc I am getting error

"java.lang.ClassNotFoundException: org.postgresql.Driver
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:264)
    at SqlConnection.sql_connection(SqlConnection.java:29)
    at ServerConnection.run(ServerConnection.java:205)
    at java.lang.Thread.run(Thread.java:745)
"

FYI I am using multiple source files. Main function is defined in one file and I am using postgresql connection in another file

Here is my src 

"private static final String DB_URL =
                          "jdbc:postgresql://127.0.0.1:5432/testdb";

        public int sql_connection(String outletid, String messageid, String checkid,int msgarry,String message,PrintStream os)
        {
                        String []lines = message.split("\\?");
                        String [] separated = lines[0].split("\\|");
                                //for(int i=0;i<4;i++)
                                  //System.out.println("received  msg from client :"+separated[i]);
                        msgformation pack = new msgformation();
                        System.out.println("sizes---: " +separated.length+" ---Arry Received: "+ msgarry);
                        if(separated.length==msgarry){
                                try{
                                        System.out.println("Connecting to database...");
                                        Properties password = new Properties();
                                        password.put("user","postgress");
                                        password.put("password","postgress");
                                        password.put("host","localhost");
                                        Class.forName("org.postgresql.Driver");
                                        //DriverManager.register(org.postgresql.Driver());
                                        ServerMain.conn = DriverManager.getConnection(DB_URL,password);

"

I have exported class path as

"export CLASSPATH=./Server.jar:~/Downloads/postgresql-9.3-1103.jdbc3.jar"

 
Server.jar is main executable file.

So please help me to solve this issue.

Thanks & Regards,

M. Nithin Chakravrthi

Software Engineer

EmbDes Technologies Pvt Ltd

#124,2nd Floor,Hosur Main Road, Madiwala,| Bangalore-68 | Karnataka, India

Tel: 080-25537562 | Mob: +91-8050597236  

Website | Email | Map

    IMVHO, I completely got rid of issues like this when I started using Maven (or Gradle or equivalent).

    I'd recommend you to do the same (and by the way, use a more modern version of the driver).

   
    Álvaro

-- 
Álvaro Hernández Tortosa


-----------
8Kdata

Hi All,

I am working on java project to insert and fetch data from postgresql database. While using jbdc I am getting error

"java.lang.ClassNotFoundException: org.postgresql.Driver
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:264)
    at SqlConnection.sql_connection(SqlConnection.java:29)
    at ServerConnection.run(ServerConnection.java:205)
    at java.lang.Thread.run(Thread.java:745)
"

FYI I am using multiple source files. Main function is defined in one file and I am using postgresql connection in another file

Here is my src 

"private static final String DB_URL =
                          "jdbc:postgresql://127.0.0.1:5432/testdb";

        public int sql_connection(String outletid, String messageid, String checkid,int msgarry,String message,PrintStream os)
        {
                        String []lines = message.split("\\?");
                        String [] separated = lines[0].split("\\|");
                                //for(int i=0;i<4;i++)
                                  //System.out.println("received  msg from client :"+separated[i]);
                        msgformation pack = new msgformation();
                        System.out.println("sizes---: " +separated.length+" ---Arry Received: "+ msgarry);
                        if(separated.length==msgarry){
                                try{
                                        System.out.println("Connecting to database...");
                                        Properties password = new Properties();
                                        password.put("user","postgress");
                                        password.put("password","postgress");
                                        password.put("host","localhost");
                                        Class.forName("org.postgresql.Driver");
                                        //DriverManager.register(org.postgresql.Driver());
                                        ServerMain.conn = DriverManager.getConnection(DB_URL,password);

"

I have exported class path as

"export CLASSPATH=./Server.jar:~/Downloads/postgresql-9.3-1103.jdbc3.jar"

 
Server.jar is main executable file.

So please help me to solve this issue.

Thanks & Regards,

M. Nithin Chakravrthi

Software Engineer

EmbDes Technologies Pvt Ltd

#124,2nd Floor,Hosur Main Road, Madiwala,| Bangalore-68 | Karnataka, India

Tel: 080-25537562 | Mob: +91-8050597236  

Website | Email | Map

Nithin Chakravarthi wrote:
> Hi All,
>
> I am working on java project to insert and fetch data from postgresql database.
> While using jbdc I am getting error
>
> "*java.lang.ClassNotFoundException: org.postgresql.Driver
>      at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
>
> ~
 > ~
 > ~
>
> //DriverManager.register(org.postgresql.Driver());
>                                          ServerMain.conn =
> DriverManager.getConnection(DB_URL,password);
>
> "
> *
> I have exported class path as
>
> *"export CLASSPATH=./Server.jar:~/Downloads/postgresql-9.3-1103.jdbc3.jar"
> *
>
> Server.jar is main executable file.
>
> So please help me to solve this issue.
> //
> Thanks & Regards,
> *M. Nithin Chakravrthi*
> Software Engineer

Hello Nithin,

Yes you can use Maven or other to build your jar or can
use the basics which is valuable in understanding the
process by compiling directly, and creating the jar
with the commands, javac, jar. Insure these are on your
execution path.

See Example Files:

   https://github.com/danap/myjsqlview

   make, build, myjsqlview.mf

   make - Compiles your source files to the specified directly.
          Use the -classpath to defines libraries, jars, required
          in the compile.

   build - Creates your jar file with included jars, your case
           and other files.

   myjsqlview.mf - specifiy the inclusion here the main class and
                   required jar, postgresql driver here.

Use the .bat files for Win, .sh for Unix/Linux.

Alternative, just place the postgresql driver in the jre/lib/ext
folder.

danap.

Zitat aus Nithin Chakravarthi's Nachricht :
> *"export CLASSPATH=./Server.jar:~/Downloads/postgresql-9.3-1103.jdbc3.jar"*

java does not expand the "~" denoting your home dir, use `pwd`
instead to let the shell do that or name the full filename
with absolute directory.

On 3/29/2016 12:16 PM, M. Dietrich wrote:
> Zitat aus Nithin Chakravarthi's Nachricht :
>> *"export
>> CLASSPATH=./Server.jar:~/Downloads/postgresql-9.3-1103.jdbc3.jar"*
>
> java does not expand the "~" denoting your home dir, use `pwd`
> instead to let the shell do that or name the full filename
> with absolute directory.

I'd suggest:

     export
CLASSPATH=./Server.jar:$HOME/Downloads/postgresql-9.3-1103.jdbc3.jar

that $HOME will get expanded when the 'set' is being done, so the value
of $CLASSPATH will contain ...:/home/whatever/Downloads/...




--
john r pierce, recycling bits in santa cruz

Nithin Chakravarthi wrote:
> Hi All,
>
> I am working on java project to insert and fetch data from postgresql database.
> While using jbdc I am getting error
>
> "*java.lang.ClassNotFoundException: org.postgresql.Driver
>      at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
>
> ~
 > ~
 > ~
>
> //DriverManager.register(org.postgresql.Driver());
>                                          ServerMain.conn =
> DriverManager.getConnection(DB_URL,password);
>
> "
> *
> I have exported class path as
>
> *"export CLASSPATH=./Server.jar:~/Downloads/postgresql-9.3-1103.jdbc3.jar"
> *
>
> Server.jar is main executable file.
>
> So please help me to solve this issue.
> //
> Thanks & Regards,
> *M. Nithin Chakravrthi*
> Software Engineer

Hello Nithin,

Yes you can use Maven or other to build your jar or can
use the basics which is valuable in understanding the
process by compiling directly, and creating the jar
with the commands, javac, jar. Insure these are on your
execution path.

See Example Files:

   https://github.com/danap/myjsqlview

   make, build, myjsqlview.mf

   make - Compiles your source files to the specified directly.
          Use the -classpath to defines libraries, jars, required
          in the compile.

   build - Creates your jar file with included jars, your case
           and other files.

   myjsqlview.mf - specifiy the inclusion here the main class and
                   required jar, postgresql driver here.

Use the .bat files for Win, .sh for Unix/Linux.

Alternative, just place the postgresql driver in the jre/lib/ext
folder.

danap.

Zitat aus Nithin Chakravarthi's Nachricht :
> *"export CLASSPATH=./Server.jar:~/Downloads/postgresql-9.3-1103.jdbc3.jar"*

java does not expand the "~" denoting your home dir, use `pwd`
instead to let the shell do that or name the full filename
with absolute directory.

On 3/29/2016 12:16 PM, M. Dietrich wrote:
> Zitat aus Nithin Chakravarthi's Nachricht :
>> *"export
>> CLASSPATH=./Server.jar:~/Downloads/postgresql-9.3-1103.jdbc3.jar"*
>
> java does not expand the "~" denoting your home dir, use `pwd`
> instead to let the shell do that or name the full filename
> with absolute directory.

I'd suggest:

     export
CLASSPATH=./Server.jar:$HOME/Downloads/postgresql-9.3-1103.jdbc3.jar

that $HOME will get expanded when the 'set' is being done, so the value
of $CLASSPATH will contain ...:/home/whatever/Downloads/...




--
john r pierce, recycling bits in santa cruz

Zitat aus John R Pierce's Nachricht :
> On 3/29/2016 12:16 PM, M. Dietrich wrote:
>> Zitat aus Nithin Chakravarthi's Nachricht :
>>> *"export
>>> CLASSPATH=./Server.jar:~/Downloads/postgresql-9.3-1103.jdbc3.jar"*
>> java does not expand the "~" denoting your home dir, use `pwd`
>> instead to let the shell do that or name the full filename
>> with absolute directory.
> I'd suggest:
>
>      export CLASSPATH=./Server.jar:$HOME/Downloads/postgresql-9.3-1103.jdbc3.jar
>
> that $HOME will get expanded when the 'set' is being done, so the value
> of $CLASSPATH will contain ...:/home/whatever/Downloads/...

correct, pwd does not do the job, sorry ;)

Zitat aus John R Pierce's Nachricht :
> On 3/29/2016 12:16 PM, M. Dietrich wrote:
>> Zitat aus Nithin Chakravarthi's Nachricht :
>>> *"export
>>> CLASSPATH=./Server.jar:~/Downloads/postgresql-9.3-1103.jdbc3.jar"*
>> java does not expand the "~" denoting your home dir, use `pwd`
>> instead to let the shell do that or name the full filename
>> with absolute directory.
> I'd suggest:
>
>      export CLASSPATH=./Server.jar:$HOME/Downloads/postgresql-9.3-1103.jdbc3.jar
>
> that $HOME will get expanded when the 'set' is being done, so the value
> of $CLASSPATH will contain ...:/home/whatever/Downloads/...

correct, pwd does not do the job, sorry ;)