how do I create bean at application startup before loading spring context?

Question

I want to create datasource bean programmatically depending on args passed from user then

public class Main {
    public static void main( String[] args ) throws IOException, InterruptedException {     
        //TODO load proper configs depending on args 
        //TODO initiate dataSource bean with UN and PS in args
        ApplicationContext context = new ClassPathXmlApplicationContext( "config/applicationContext-common.xml" );
   }
}

I've done a little googling already and found that I have to create a post processor bean that creates a data source bean and programmatically configures it using the fetched data. What I'd like to see is a real example.

Answer 1

You can try the code below, it should inject dataSource before wiring.

public class Main {
    public static void main( String[] args ) throws IOException, InterruptedException {     
        //TODO load proper configs depending on args 
        //TODO initiate dataSource bean with UN and PS in args
        ApplicationContext context = new ClassPathXmlApplicationContext("config/applicationContext-common.xml") {
          protected void prepareBeanFactory(ConfigurableListableBeanFactory beanFactory) {
           super.prepareBeanFactory(beanFactory);
           beanFactory.registerSingleton("dataSource", dataSource);
          }
        };
   }
}