/* The DataStructureException class Anderson, Franceschi */

public class DataStructureException extends Exception { public DataStructureException( String s ) { super( s ); } }

/* StackArray * Anderson, Franceschi */

import java.awt.Graphics; import javax.swing.JFrame; import java.awt.Color;

public class StackArray { public static final int CAPACITY = 10;

private int[] stack; private int top;

public StackArray() { stack = new int[CAPACITY]; top = -1; }

public int get(int index) { return stack[index]; }

public int getTop() { return top; }

/** * push method * * @param value value to be pushed onto the stack * @return true if successful, false if unsuccessful */ public boolean push(int value) { // ***** 1. Student code starts here ***** // stack is an int array instance variable representing // the array that stores our stack

// top is an instance variable representing // the index of the top of the stack // CAPACITY is a constant instance variable representing // the size of the array stack // The push method adds the argument value // to the top of the stack, if it is possible // code the push method here // Part 1 student code starts here:

return true; // replace this dummy return statement

// Part 1 student code ends here. }

/** * pop method * * @return the value of the top element of the stack, if successful */ public int pop() throws DataStructureException { // ***** 2. Student code restarts here ***** // stack is an int array instance variable representing // the array that stores our stack

// top is an instance variable representing // the index of the top of the stack // CAPACITY is a constant instance variable representing // the size of the array stack // The pop method deletes the element // at the top of the stack, if it is possible // Code the pop method here // Part 2 student code starts here:

return 0; // replace this dummy return statement

// Part 2 student code ends here. } }

/* StackArrayDrawing * Anderson, Franceschi */

import java.awt.Graphics; import javax.swing.JFrame; import java.awt.Color;

public class StackArrayDrawing { public static final int XSTART = 200; public static final int YSTART = 300; public static final int WIDTH = 100; public static final int HEIGHT = 25;

private StackArray sa;

private boolean pushSuccess; private boolean popSuccess; private int pushedValue; private int poppedValue;

private boolean operation; // true for push, false for pop private String description = ""; private boolean started;

public StackArrayDrawing( ) { sa = new StackArray( ); }

public void setPushSuccess( boolean newPushSuccess ) { started = true; pushSuccess = newPushSuccess; }

public void setPopSuccess( boolean newPopSuccess ) { popSuccess = newPopSuccess; }

public void setPushedValue( int newPushedValue ) { pushedValue = newPushedValue; }

public void setPoppedValue( int newPoppedValue ) { poppedValue = newPoppedValue; }

public void setOperation( boolean newOperation ) { operation = newOperation; }

public void setStarted( boolean newStarted ) { started = newStarted; }

public boolean push( int value ) { return ( sa.push( value ) ); }

public int pop( ) throws DataStructureException { return( sa.pop( ) ); }

public void draw( Graphics g ) { // draw the empty stack and indices g.setColor( Color.BLUE ); drawEmptyStack( g );

// draw the stack contents g.setColor( Color.RED ); drawStackContents( g );

// draw top g.setColor( Color.BLACK ); drawTop( g );

// determine operation if ( operation ) // push { if ( pushSuccess ) { description = "successfully pushed " + pushedValue; } else { description = "failed to push " + pushedValue; } } else // pop { if ( popSuccess ) { description = "successfully popped " + poppedValue; } else { description = "failed to pop"; } } if ( !started ) description = ""; drawDescription( g ); }

public void drawEmptyStack( Graphics g ) { for ( int i = 0; i < StackArray.CAPACITY; i++ ) { g.drawRect( XSTART, YSTART - i * HEIGHT, WIDTH, HEIGHT ); g.drawString( "" + i, XSTART - WIDTH / 4, (int) ( YSTART - ( i - 0.7 ) * HEIGHT ) ); } }

public void drawStackContents( Graphics g ) { int i = 0; g.setColor( Color.BLACK ); for ( i = 0; i <= sa.getTop( ); i++ ) { g.drawString( "" + sa.get( i ), XSTART + WIDTH / 2 - 5, (int) ( YSTART - ( i - 0.7 ) * HEIGHT ) ); } g.setColor( Color.RED ); for ( i = sa.getTop( ) + 1; i < StackArray.CAPACITY; i++ ) { g.drawString( "" + sa.get( i ), XSTART + WIDTH / 2 - 5, (int) ( YSTART - ( i - 0.7 ) * HEIGHT ) ); } }

public void drawTop( Graphics g ) { g.drawString( "top", XSTART - WIDTH / 2, (int) ( YSTART - ( sa.getTop( ) - 0.7 ) * HEIGHT ) ); }

public void drawDescription( Graphics g ) { g.drawString( description, XSTART + WIDTH + 20, YSTART / 2 ); } }

/* StackPractice * Anderson, Franceschi */

import java.awt.*; import javax.swing.*; import java.awt.event.*;

public class StackPractice extends JFrame { Container contents; // GUI components private JButton push; private JButton pop;

private ButtonHandler bh;

private StackArrayDrawing sad;

private static StackPractice app; private boolean firstTime = true;

public StackPractice( ) { super( "Push or pop" ); contents = getContentPane( ); contents.setLayout( new FlowLayout( ) );

sad = new StackArrayDrawing( );

push = new JButton( "push" ); contents.add( push ); pop = new JButton( "pop" ); contents.add( pop );

bh = new ButtonHandler( ); push.addActionListener( bh ); pop.addActionListener( bh );

setSize( 500,400 ); setVisible( true ); }

private void animate( boolean pushSuccess, int pushedValue ) { sad.setPushSuccess( pushSuccess ); sad.setPushedValue( pushedValue ); try { repaint( ); Thread.sleep( 200 ); } catch ( InterruptedException e ) { System.out.println( "IE Exception " + e.getMessage( ) ); System.out.println( e.toString( ) ); } }

private void animate( int poppedValue ) { sad.setPopSuccess( true ); sad.setPoppedValue( poppedValue ); try { repaint( ); Thread.sleep( 200 ); } catch ( InterruptedException e ) { System.out.println( "IE Exception " + e.getMessage( ) ); System.out.println( e.toString( ) ); } }

private void animate( ) { sad.setPopSuccess( false ); try { repaint( ); Thread.sleep( 200 ); } catch ( InterruptedException e ) { System.out.println( "IE Exception " + e.getMessage( ) ); System.out.println( e.toString( ) ); } }

public void paint( Graphics g ) { if ( firstTime ) firstTime = false; super.paint( g ); sad.draw( g ); }

public static void main( String [] args ) { app = new StackPractice( ); app.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE ); }

private class ButtonHandler implements ActionListener { private boolean success = false;

public void actionPerformed( ActionEvent e ) { sad.setStarted( true ); if ( e.getSource( ) == push ) { sad.setOperation( true ); int insertValue = getValue( ); success = sad.push( insertValue ); animate( success, insertValue ); } else // ( e.getSource( ) == pop ) { sad.setOperation( false ); try { int popped = sad.pop( ); animate( popped ); } catch( DataStructureException dse ) { System.out.println( dse.getMessage( ) ); animate( ); } } } }

public int getValue( ) { int value = 0; boolean goodInput = false; while ( !goodInput ) { try { String answer = JOptionPane.showInputDialog ( null, "Enter an integer value" ); value = Integer.parseInt( answer ); goodInput = true; } catch( Exception e ) { } } return value; } }