example of drying up code through inheritance, the facade pattern, and convention over configuration

modelshow.java

// Get a model from the database, client says
Connection conn = DatabaseConnectionHelper.getConnection(); // make this static
DBFacade db = new DBFacade( conn );
ExampleModel exModel = ExampleModel.find( db, 15 );
exModel.setName('blah').save();
exModel.delete();

// classes
public class SuperModel {

    protected DBFacade db;
    protected Map row;

    public SuperModel( DBFacade db, int id ) {
        this.db = db;
    }
    
    /**
     * Get the name of the table by figuring out the name of this model
     * and using that as the table name (minus Model)
     * ( you could also store a constant in the child table called TABLE_NAME )
     */
    final public String getTable() {
        
        String[] strings = this.getClass().getName().split("\\."); // split the package/class
        String className = strings[1];
        
        // Build the table name
        return className.substring(0, className.length()-5).toLowerCase();
    }
    
    private void populateModel( int id ) {
        Map where = new Map<String, String>();
        where.put( 'id', id.toString() );
        row = this.db.where( where ).get( this.getTable() );
    }
    
    public void delete() {
        Map where = new Map;
        where.put( 'id', this.row.get('id') );
        this.db.where( where ).delete( this.getTable() );
    }
    
    public void save() {
        // need to detect if this is an insert or an update
    }
    
    /**
     * Act as a mini factory in static context
     */

}

public class ExampleModel extends SuperModel {

    public ExampleModel( DBFacade db, int id ) {
        super( db, id );
    }
    
    public static ExampleModel find( DBFacade db, int id ) {
        return new ExampleModel( db, id );
    }

    public String getName() {
        return this.row.get('name');
    }
}

public class DBFacade {
 
    private Connection conn;
    
    public int lastInsertId() {
    
    }
    
    public ArrayList getColumnList() {

    }

    public DBFacade where() {
        
        return this;
    }
    
    public DBFacade select() {
        
        return this;
    }
    
    public Map get( String table ) throws SQLException  {
        
    }

    public DBFacade insert( Map data, String table ) throws SQLException  {
 
        return this;
    }
    
    public DBFacade update( Map data, String table ) throws SQLException {
        
        return this;
    }

    public DBFacade delete( String table ) throws SQLException {

    }
}