AbstractDbAccessBatch

Class Information

Package: com.onepg.bat

Class Name: AbstractDbAccessBatch (Abstract Class)

Description

Base class for database access batch processing.

Base class for batch processing that includes database connections.
Automatically handles database connection acquisition and closing.
Provides common processing (logging, exception handling, etc.) for each batch.
Subclasses define specific batch processing by implementing the doExecute method.
When a subclass calls the callMain method of this class from the main method, the doExecute method is executed.
Arguments to the subclass main method are assumed to be passed as-is to the callMain method in URL parameter format.
Arguments in URL parameter format are converted to map format and passed to the doExecute method as an IoItems instance.
When an error occurs in the subclass doExecute method, it is assumed to throw an Exception.
The return value of the callMain method on successful completion is 0.
The return value of the callMain method when an Exception is thrown in the doExecute method is 1.

[Implementation Example] public class ExampleBatch extends AbstractDbAccessBatch {
   public static void main(String[] args) {
     System.exit((new ExampleBatch()).callMain(args));
   }


    
      Constants and Variables
      
        
          traceCode
          
            protected String traceCode
          
          
            Trace code. 
          
        
        
          logger
          
            protected LogWriter logger
          
          
            Log writer. 
          
        
      
    
    
      Method List
      
        doExecute (Abstract Method)
        
          protected void doExecute(IoItems args)
        
        
          Main processing.


Subclasses implement specific batch processing.


        
        
          Parameters
          
            
              
                Name
                Type
                Description
              
            
            
              
                args
                IoItems
                arguments
              
            
          
        
      
      
        callMain
        
          protected int callMain(String[] args)
        
        
          Invokes main processing.


Converts arguments from URL parameter format to map format, executes log start processing, and then calls the doExecute method.
Accepts multiple arguments as an array to handle length limitations per command line argument.
The converted arguments are passed to the doExecute method as an IoItems instance.
If an Exception is thrown in the doExecute method, the processing is considered to have terminated abnormally.
Commits when the processing completes successfully.
Rolls back when the processing terminates abnormally. (The rollback itself is performed by Connection#close())
Always closes the database connection after processing ends.


        
        
          Parameters
          
            
              
                Name
                Type
                Description
              
            
            
              
                args
                String[]
                arguments
              
            
          
        
        
          Return Value
          int - 0 on successful completion, 1 on abnormal termination
        
      
      
        getDbConn
        
          protected Connection getDbConn()
        
        
          Retrieves database connection.


Returns the current database connection.
The connection is valid only within the callMain method.


        
        
          Return Value
          Connection - the database connection