Connection object in other classes

i am writing a JDBC application. There will only be one user for this application.
I want to know whether i am doing it the right way.
Main program sets the connection to database and provides a static method getDBConnection()
which returns a Connection object .
All other programs have a public final variable which gets initialized with getDBConnection() method .
Is there any other way other programs can get connection to database?
I would appreciate any suggestions.
Thanks

sorry..
all the other classes have public static variable which gets initialized with static method(getDBConnection) of main class(the method returns a connection)

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How to store Connection object and call it from other programs.

Hi,
I am trying to connect to the database, store the connection object and use this connection object from other standalone java programs.
Can any one tell me how to do this? I've tried in the following way:
In the following program I am connecting to the database and saving the connection object in a variable.
public class GetKT2Connection {
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      if(kt2conn == null) {
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} Here is the program to save connection object in a variable.
public class GetKTConnectionObj {
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   kt2Connection = conn;
   public static Connection getKT2ConnectionObj() {
   try {
      return kt2Connection;
   catch(Exception e){
      System.out.println(e);
return null;
}Now from the following code I am trying to get the connection object that is stored. But this is throwing NullPointerException.
public class Metrics_Migration {
public static void main(String args[]) {
     try {
    java.sql.Connection connection_1 =   GetKTConnectionObj.getKT6ConnectionObj();
     catch(Exception e){
}

kt2Connection is null. You need to store it first, to make it not null. Otherwise it will stay null forever. And why on earth are you trying to do this THIS way?
If you are running the two applications separately, it wont work either.

Getting the connection object in graph

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As part of Denormalizer component's Denormalize property where we have the logic of collapsing/denormalising the records we want to execute a sql query using PreparedStatement which requires Connection object.how do I get the connection object and execute a query.Can some one please share the java doc of the classes I can use.
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Hensome wrote:
1. But how do I use the managed bean within a servlet? Could you write some simple sample codes?
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I was looking at one of the database examples in a Java book I recently purchased. In their example they establish the connection in the class with the main. ( is this referred to as the Moment Interval? ) Anyway, they pass the private Connection connection object to another class called AddRecord which implements an ActionListener. In this class, the AddRecord Constructor changes the name to con which is also declared as private in this class. What they don't show is how to close the connection object now that it has a new name. How do I close the connection object.
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I'm sorry. I meant to say "Where" do I close the connection? If I close the connection in the AddRecord Class, then I won't be able to add another record. And I can't close the connection in the moment interval because I've declared the connection object in class AddRecord as Private. Should I give the connection object package access?
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Hello Sir,
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Like that:
one.java
package co;
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kumar.vijaydahiya wrote:
.It is set in environment variable.path=C:\bea\jdk141_02\bin;.,C:\oraclexe\app\oracle\product\10.2.0\server\bin;. command is:
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Making object accesible from other class?

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Help required: Using objects/methods in other classes

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Say you have a class that has a private string instance variable and you have a accessor and mutator method for this object in that class.
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Kayaman gave you the right answer
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Also When you aks a question a little humility doesnt hurt.
You do need a tutorial first.

How do i create objects of ordinary Classes from a javabean

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Look below Person class definition for continuation.
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How many Connections objects????

Hi
I am creating a GUI application which contains several GUI classes(e.g. frames and dialog boxes) which are instantiated depending on the choice of the user. I also have a Database class which contains the code which enables the connection to the database. The code creating the connection is within the constructor,therefore creating a connection whever I create an instance of the database class.
Most of the GUI classes need to obtain or update information held in a database.
Currently I create an instance of the Database class in every GUI class which needs to access the database. Obviously however every time a new database object is created, a new connection is also created.
I am worried about all these database objects all containing their own connections.
Should I have just one connection object in existence at any one time?
If so,can I declare the Connection variable in the Database class as static?
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Connection object as a key in a hashtable

Hi,
I am debugging some code where a Connection object is used as a key in a hashtable. Is this ok? Will the equals() and hashCode method be defined properly for a Connection object?
Appreciate your help.
Thanks!

I am debugging some code where a Connection object is
used as a key in a hashtable. Is this ok? Will the
equals() and hashCode method be defined properly for a
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Vlad.

Connection object in other classes

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