JAVA create JTable using Vector() and one class

Note: This example assumes that a connection class already exists. 

/**

 * Fields

 **/

     // Connection variables.

     Connection conn = null;

     PreparedStatement pst = null;

     static ResultSet rst = null;

     private Vector columnNames = new Vector();

     private Vector data = new Vector();

     private JTable tblData = new JTable();

     private DefaultTableModel model;

    

     private JPanel pnl_Data = new JPanel();

     …

     …                              

     …

/**

 *Constructor

 **/

public Class(){

     Connect_to_database ctb = new Connect_to_database();

     conn = ctb.ConnectDb();

    

     createTable();

     …

     …   

     …

    

     pnl_Data.setBorder(new TitledBorder(null, "Data", TitledBorder.CENTER, TitledBorder.TOP, null, Color.BLUE));

     pnl_Data.setBackground(Color.WHITE);

     pnl_Data.setBounds(570, 11, 636, 850);

     contentPane.add(pnl_Data);

}

/**

 * Load table Data Method

 **/

public void reloadData(){

     columnNames.clear();

     data.clear();

          

     try {

           String sql = "SELECT * FROM User_tb“;

          

           pst = conn.prepareStatement(sql);

           rst = pst.executeQuery();

           ResultSetMetaData md = rst.getMetaData();

           int columns = md.getColumnCount();

               

           for (int i = 1; i <= columns; i++) {

                columnNames.addElement( md.getColumnName(i) );

           } while (rst.next()) {

                Vector row = new Vector(columns);

                for (int i = 1; i <= columns; i++){

                     row.addElement( rst.getObject(i) );

                }

                data.addElement( row );

           }

           rst.close();

           pst.close();

     } catch (Exception e) {

           System.out.println("Error at reloadData()" + e);

     }

}

/**

 * Create table method

 **/

public void createTable() {

     reloadData();

               

     try {

           model = new DefaultTableModel(data, columnNames);

           tblData = new JTable(model);

                    

           tblData.setBounds(10, 829, 616, -802);

           JScrollPane scroll = new JScrollPane(tblData, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);

           tblData.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);

           scroll.setBorder(null);

           tblData.setBorder(null);

           scroll.setPreferredSize(new Dimension(610, 809));

           pnl_Data.add(scrollCPL);

     } catch (Exception e) {

           System.out.println("Error at createTable()" + e);

     }

}

by: Michael Lashley

Sum/Addition Minijava Program

//By Michael Lashley 

//The following program states what the followiing code does for example, it sums all the numbers 
//in an array and returns the overall total. 

//Class is created
class AdditionTestMini
{
    public static void main(String[] a){ 
System.out.println(((new Sum()).init()).sumAdd());
    }
}

//class is created for the sum of enteries 
class Sum
{
    int[] data;
        
    //below the line of code "getLenght" returns the length of the array (number of elements in the array).
    public int getLength()
    {
        return data.length;
    }

    //this method initials values to specific positions in the array.
    public Sum init()
    {  
        
int index;
        data = new int[5];
        data[0] = 4;
        data[1] = 6;
        data[2] = 8;
        data[3] = 12;
        data[4] = 14;
        return this;               
    }

    //this method calculates/add together the value of all elements in the array stated above.
    public int sumAdd()
    {
        int i;
        int total; 
        int current;
        current = 0;/
        total = 0;
        i = 0;

        //this while loop checks the condition, that the current position in the array is less than the length of the array.
        while (i < (data.length)){
                current = data[i];
                total = total + current;
                i = i + 1;
        }  
        return total;    
    }    
}

MiniJava Grammar

This image shows a reconstructed version of the standard mini java grammar which avoids left-recursion and ambiguity. During my Language Processors module I had the pleasure of working with this mini java grammar firstly to write a program using this grammar, secondly to complete write a .jj file which will parse a selected list of mini java programs and lastly to program a type checker and interpreter for the grammar. Compared to standard java mini java should be simpler but having learnt standard java first it was a challenge getting to grips with a this grammar, nonetheless I enjoyed every second of this module...

Functional Programming Code

 

-----------------------------------------------------------------------------
-- |
-- Module      :  MyAnimation
-- Copyright   :  (c) Michael Lashley 2012
-- License     :  NA
-- Maintainer  :  Michael Lashley
-- Stability   :  experimental
-- Portability :  portable
--
-- A animation called "The Impossible".
-- This animation is a series of squares which change scale while spining
-- around a central orbit/gravitational pull.
--
-----------------------------------------------------------------------------

 

module MyAnimation where

 

-- Import libraries functions from the Animation .hs file.

 

import Animation

 

-- The spin function takes two inputs of type int and returns an animation.
-- This function applies functions from the Animation library to each rect object created by the list in the Picture function.

 

spin :: Int -> Int -> Animation
spin i j =
  rotate (spinner k)
   (rotate (ever z)
    (translate (ever (-x/2, -x/2))
     (withGenPaint (cycleSmooth (x/10) [c, yellow, lime, purple, cyan, grey, olive]) (cycleSmooth 7 [0.2, 1])
      (rect (cycleSmooth 10 [x/2, 1.5]) (cycleSmooth 5 [6*x, 20])))))

 where
    x = fromIntegral j
    c = hsl (fromIntegral i * 45) 1 0.5
    z = fromIntegral(i `mod` 2) * 45
    k = -10 + 0.5*fromIntegral i

 

-- The picture function returns and animation.
-- This function calls the Spin function in a list compression with defined variables i and x.

 

picture :: Animation
picture =

 withPaint (ever black)
   (rect (ever 800) (ever 600)) `plus`

 translate (ever (400, 300))
 (combine [spin i x | i <- [0..16], x <- [350, 150..50]])

 

-- "test" is a function that writes/creates a .svg file when called.
-- The test.svg file invokes the Picture function there for starting the animation.

 

test :: IO ()
test = writeFile "test.svg" (svg 800 600 picture)

Functional Programming Animation

Note: The image below will play best on web browsers Chrome and Firefox.

This animation was created using the Haskell programming language.