Question

Currently I made a connection to a database in this way:

MyClass.java

try {
    DataSource datasource = JNDILoader.getDataSourceObject(pathToSource);
    Class.forName("net.sourceforge.jtds.jdbc.Driver");
    connection = datasource.getConnection();
    stmt = connection.prepareStatement("{call storageProcedureXXX(?,?)}");
    stmt.setString(1, "X");
    stmt.setString(2, "Y");            
    result = stmt.executeQuery();
}catch (SQLException){
    //TODO
}catch(Exception){
    //TODO
} 

That works for 1 class that makes the requests for the data, but , would be better if I create a singleton class and get the connection from it? (performance?, maintenability?, simplicity?). Which option would be better: Singleton vs StorageProcedures per each request?.

Note: At the end, the application (Restful Web Service) will need to connect to different databases to load data for different specialized classes, even , the classes would need loads data from plain text.

Answer 1

First of all you are mixing two different things: singleton and stored procedures. Singleton is design pattern, and stored procedures are procedures executed on database, typically encapsulating some business logic.

What you wrote is not really preferred way of connecting to database. If you have many request and create one connection for each request son you will have problems with too many connections to database. You should use connection pool. The most famous for Java is DBCP. Another one is c3p0.

For connection on different databases you should use something like Hibernate.