Painters (java.awt.Paint interface)

Hello,
I would like to implement a collection of painters (like GradientPaint, TexturePaint ..). Unfortunatelly, I found little information regarding this topic on the web. I found out that I need to implement the java.awt.Paint interface (and everything that it implies: PaintContext etc..). Do you know of any web site that might have some form of collection of this painters, or more complex information like algorithms for simple textures...Mabe I am asking the question wrong, that's why any links to basic resources that I can start with are welcome. I have allready taken a look at :
http://swing-fx.blogspot.com/2008/05/glossy-and-shiny-shapes-with-paint-and.html
http://drj11.wordpress.com/2007/04/02/subclassing-javaawtpaint/
These helped me to understand the logic..but I feel left somwhere in the air with only this information.
Any help is appreciated!
Regards,
Radu Cosmin

Similar Messages

If Statement in java.awt paint

import java.applet.Applet; //bring in the applet class
import java.awt.*; //bring in the graphics class
import java.awt.event.*; //bring in the event class
import java.text.DecimalFormat; //bring in the decimal format class
import java.lang.Float; //bring in the float class
public class Bmi extends Applet implements ActionListener { //begin program and start ActionListener
Label weight, height; //define Label variable
TextField weighttext, heighttext; //define TextField variables
Button calculate; //define button variables
float index, wt, ht, max, min; //define float variables
DecimalFormat fmt2 = new DecimalFormat("#.00"); //set decimal format for reals
public void init() { //begin init()
weight = new Label("Please enter your weight in Kg. (2 decimal places): "); //define content of Label weight
weighttext = new TextField(6); //define size of TextField
height = new Label("Please enter your height in Metres (2 decimal places): "); //define content of Label height
heighttext = new TextField(5); //define size of TextField
calculate = new Button("Calculate!!"); //define content of Button
add(weight); //add Label weight to the GUI
add(weighttext); //add TextField weighttext to the GUI
add(height); //add Label height to the GUI
add(heighttext); //add TextField heighttext to the GUI
add(calculate); //add button calculate to the GUI
calculate.addActionListener(this); //wait for button to be returned
wt = 0; //reset wt to 0
index = 0; //reset index to 0
ht = 0; //reset ht to 0
max = 0; //reset max to 0
min = 0; //reset min to 0
public void actionPerformed( ActionEvent e ) { //run upon return of button
wt = Float.parseFloat(weighttext.getText()); //convert weighttext from String to Float
ht = Float.parseFloat(heighttext.getText()); //covert heighttext from String to Float
repaint(); //refresh paint area
public float indexer() //begin indexer method
 float ind; //delare local variable ind
 ind = wt/(ht*ht); //perform calculation
 return ind; //make indexer() the value of variable ind
} // end of indexer method
public float maxWeight() //begin maxWeight method
 float maxwt; //declare local variable maxwt
 final float UPPER = 25.0f; //declare variable UPPER as a float with a decimal value of 25.0
 maxwt = UPPER*ht*ht; //perform calculation
 return maxwt; //make maxWeight() the value of variable maxwt
} // end of maxWeight method
public float minWeight() //begin minWeight method
 float minwt; //declare local variable minwt
 final float LOWER= 20.0f; //declare variable LOWER as a float with a decimal value of 20.0
 minwt = LOWER*ht*ht; //perform calculation
 return minwt; //make minWeight() the value of variable minwt
} // end of minWeight method
public void paint(Graphics g) //begin paint method, define g as Graphics
 index=indexer(); //covert method indexer() to variable index
 max=maxWeight(); //convert method maxWeight() to variable max
 min=minWeight(); //convert method minWeight() to variable min
 g.setFont(new Font("Verdana", Font.ITALIC, 15)); //define font, weight and size
 g.setColor(new Color(90,90,90)); //set new colour
 g.drawRect(5,100,300,75); //define size of rectangle
 g.setColor(new Color(255,107,9)); //set new colour
 g.drawString("BMI is " + fmt2.format(index) + " for " + fmt2.format(wt) + "kg",20,120); //create string in paint, define its on screen position
 g.drawString("Maximum bodyweight is " + fmt2.format(max) + "kg", 20,140); //create string in paint, define its on screen position
 g.drawString("Minimum bodyweight is " + fmt2.format(min) + "kg", 20,160); //create string in paint, define its on screen position
} // end of paint method
} // end of Bmi classI have written the above code to calculate someones BMI (Body Mass Index). Basically as you can see it recieves a weight and height from the user and calculates the rest. But whilst that good I would like to know how I can make it tell the user something to the effect of "Your overweight" or "Your underweight". The if statement runs like this:
if (wt > max)This forum doesn't quite handle <> properly. The greater and less than symbols. So above you will see > this is the html character code for a greater than symbol so please read it as such.
And then if wt is greater than max then it will say "Your overweight".
But I can't figure out how to include it in the above program. Becuase it won't run in paint, atleast it won't the way I have done it previously. So can you think of any other ways?
Help much appreciated,
Simon

Thanks very much that works well.
Simon
My code now looks like this: import java.applet.Applet; //bring in the applet class
import java.awt.*; //bring in the graphics class
import java.awt.event.*; //bring in the event class
import java.text.DecimalFormat; //bring in the decimal format class
import java.lang.Float; //bring in the float class
public class Bmi extends Applet implements ActionListener { //begin program and start ActionListener
Label weight, height; //define Label variable
TextField weighttext, heighttext; //define TextField variables
Button calculate; //define button variables
float index, wt, ht, max, min; //define float variables
DecimalFormat fmt2 = new DecimalFormat("#.00"); //set decimal format for reals
public void init() { //begin init()
weight = new Label("Please enter your weight in Kg. (2 decimal places): "); //define content of Label weight
weighttext = new TextField(6); //define size of TextField
height = new Label("Please enter your height in Metres (2 decimal places): "); //define content of Label height
heighttext = new TextField(5); //define size of TextField
calculate = new Button("Calculate!!"); //define content of Button
add(weight); //add Label weight to the GUI
add(weighttext); //add TextField weighttext to the GUI
add(height); //add Label height to the GUI
add(heighttext); //add TextField heighttext to the GUI
add(calculate); //add button calculate to the GUI
calculate.addActionListener(this); //wait for button to be returned
wt = 0; //reset wt to 0
index = 0; //reset index to 0
ht = 0; //reset ht to 0
max = 0; //reset max to 0
min = 0; //reset min to 0
public void actionPerformed( ActionEvent e ) { //run upon return of button
wt = Float.parseFloat(weighttext.getText()); //convert weighttext from String to Float
ht = Float.parseFloat(heighttext.getText()); //covert heighttext from String to Float
repaint(); //refresh paint area
public float indexer() //begin indexer method
 float ind; //delare local variable ind
 ind = wt/(ht*ht); //perform calculation
 return ind; //make indexer() the value of variable ind
} // end of indexer method
public float maxWeight() //begin maxWeight method
 float maxwt; //declare local variable maxwt
 final float UPPER = 25.0f; //declare variable UPPER as a float with a decimal value of 25.0
 maxwt = UPPER*ht*ht; //perform calculation
 return maxwt; //make maxWeight() the value of variable maxwt
} // end of maxWeight method
public float minWeight() //begin minWeight method
 float minwt; //declare local variable minwt
 final float LOWER= 20.0f; //declare variable LOWER as a float with a decimal value of 20.0
 minwt = LOWER*ht*ht; //perform calculation
 return minwt; //make minWeight() the value of variable minwt
} // end of minWeight method
public void you(Graphics g)
String statement;
if(wt > max) statement="You are very fat";
else if(wt < min) statement="You are very thin";
else statement="You are in the recommended weight range for your height";
g.drawString(statement, 20,210);
public void paint(Graphics g) //begin paint method, define g as Graphics
 you(g);
 index=indexer(); //covert method indexer() to variable index
 max=maxWeight(); //convert method maxWeight() to variable max
 min=minWeight(); //convert method minWeight() to variable min
 g.setFont(new Font("Verdana", Font.ITALIC, 15)); //define font, weight and size
 g.setColor(new Color(90,90,90)); //set new colour
 g.drawRect(5,100,300,75); //define size of rectangle
 g.setColor(new Color(255,107,9)); //set new colour
 g.drawString("BMI is " + fmt2.format(index) + " for " + fmt2.format(wt) + "kg",20,120); //create string in paint, define its on screen position
 g.drawString("Maximum bodyweight is " + fmt2.format(max) + "kg", 20,140); //create string in paint, define its on screen position
 g.drawString("Minimum bodyweight is " + fmt2.format(min) + "kg", 20,160); //create string in paint, define its on screen position
} // end of paint method
} // end of BmiThanks again,
Simon

A Bean must implement the java.io.Serializable interface? What makes the di

Hi, I have took an example from sun notes on JavaBeans (you can find the example here http://java.sun.com/developer/onlineTraining/Beans/beans02/page2.html). The code is like this.....
import java.awt.*;
import java.io.Serializable;
public class SimpleBean extends Canvas
                 implements Serializable {
private Color color = Color.green;
//getter method
public Color getColor() {
     return color;
//setter method
public void setColor(Color newColor) {
     color = newColor;
     repaint();
//override paint method
public void paint (Graphics g) {
     g.setColor(color);
     g.fillRect(20,5,20,30);
//Constructor: sets inherited properties
public SimpleBean() {
     setSize(60,40);
     setBackground(Color.red);
}I didn't find any difference in executing the program by implementing the Serializable interface and without implementing. On choosing serialize component in the File Menu, I serialized the component after changing its color (property), and saved as .ser file. And created the .Jar file including .ser file. when I load the jar file and place the bean in the beanbox, it is showing the bean that is updated. This can be done by implemeting Serializable interface and without implementing Serializable interface also. And I have a statement that has been given in the notes provided by SUN. That is ' Bean must implement the Serializable interface. Objects that support this interface can save and restore their state from disk '. I couldnot come up with the summation of this statement.
Anyone who has an idea... please give an explanation.
Thank you.

Maybe you should show us your coding how you saved your beans state.
Are you serious that you save the special object? Or do you save the values of the object into a file and load those values into a new object?

The method add() in java.awt.Container made me in confuse

Here is my two java code file:
//MyContainer.java
package sam.gui;
import java.awt.Dimension;
import java.awt.Graphics;
import javax.swing.JApplet;
import javax.swing.JFrame;
public class MyContainer extends JApplet {
 private MyButton[] myButton = new MyButton[2];
 private static int counter = 0;
 public MyContainer() {
 myButton[0] = new MyButton(5, 5, 200, 30);
 myButton[1] = new MyButton(5, 40, 200, 30);
 for (int i = 0; i < myButton.length; i++) {
 add(myButton);
 public void paint(Graphics g) {
 for (int i = 0; i < myButton.length; i++) {
 System.out.println("MyButton : " + (i+1));
 myButton[i].draw(g);
 public static void main(String[] args) {
 MyContainer container = new MyContainer();
 JFrame f = new JFrame();
 f.getContentPane().add(container);
 f.pack();
 f.setSize(new Dimension(300, 200));
 f.show();
//MyButton.java
package sam.gui;
import java.awt.Color;
import java.awt.Component;
import java.awt.Graphics;
import java.awt.Graphics2D;
public class MyButton extends Component {
 private Color m_rectColor = new Color(128, 73, 0);
 public MyButton(int x, int y, int width, int height) {
 setBounds(x, y, width, height);
 public void draw(Graphics g) {
 Graphics2D g2 = (Graphics2D)g;
 g.setColor(m_rectColor);
 g.fillRect(0, 0,
 getBounds().width, getBounds().height);
 System.out.println("x = " + getBounds().x);
 System.out.println("y = " + getBounds().y);
 System.out.println("width = " + getBounds().width);
 System.out.println("height = " + getBounds().height);
I thinked the runned result should be below:
MyButton : 1
x = 5
y = 5
width = 200
height = 30
MyButton : 2
x = 5
y = 40
width = 200
height = 30But in fact, its result is here:
MyButton : 1
x = 5
y = 5
width = 200
height = 30
MyButton : 2
x = 0
y = 0
width = 292
height = 173I don't know why the result would like this? I have used add(...) method to add two component MyButton to the container MyContainer, But the bounds of the second component is not I want.
So this problem made me go into confuse.

You need to learn how layout managers work. The default layout manager of a JApplet and JFrame is BorderLayout .
/Kaj

Custom graphics in java.awt.ScrollPane

Hi all,
I have to draw a custom created image in a scroll pane. As the image is very large I want to display it in a scroll pane. As parts of the image may change within seconds, and drawing the whole image is very time consuming (several seconds) I want to draw only the part of the image that is currently visible to the user.
My idea: creating a new class that extends from java.awt.ScrollPane, overwrite the paint(Graphics) method and do the drawings inside. Unfortunately, it does not work. The background of the scoll pane is blue, but it does not show the red box (the current viewport is not shown in red).
Below please find the source code that I am using:
package graphics;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.ScrollPane;
import java.awt.event.AdjustmentEvent;
public class CMyComponent extends ScrollPane {
 /** Listener to force a component to repaint when a scroll bar changes its
 * position.
 private final class ScrollBarAdjustmentListener implements java.awt.event.AdjustmentListener {
 /** The component to force to repaint. */
 private final Component m_Target;
 /** Default constructor.
 * @param Target The component to force to repaint.
 private ScrollBarAdjustmentListener(Component Target) { m_Target = Target; }
 /** Forces to component to repaint upon adjustment of the scroll bar.
 * @see java.awt.event.AdjustmentListener#adjustmentValueChanged(java.awt.event.AdjustmentEvent)
 public void adjustmentValueChanged(AdjustmentEvent e) { m_Target.paint(m_Target.getGraphics()); }
 public CMyComponent() {
 // Ensure that the component repaints upon changing of the scroll bars
 ScrollBarAdjustmentListener sbal = new ScrollBarAdjustmentListener(this);
 getHAdjustable().addAdjustmentListener(sbal);
 getVAdjustable().addAdjustmentListener(sbal);
 public void paint(Graphics g) {
 setBackground(Color.BLUE);
 g.setColor(Color.RED);
 g.fillRect(getScrollPosition().x, getScrollPosition().y, getViewportSize().width, getViewportSize().height);
 public final static void main(String[] args) {
 java.awt.Frame f = new java.awt.Frame();
 f.add(new CMyComponent());
 f.pack();
 f.setVisible(true);
}

Dear all,
I used the last days and tried several things. I think now I have a quite good working solution (just one bug remains) and it is very performant. To give others a chance to see what I have done I post the source code of the main class (a canvas drawing and implementing scrolling) here. As soon as the sourceforge project is accepted, I will publish the whole sources at there. Enjoy. And if you have some idea for my last bug in getElementAtPixel(Point), then please tell me.
package internetrail.graphics.hexgrid;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Point;
import java.awt.Polygon;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;
import java.awt.geom.Area;
import java.awt.image.BufferedImage;
import java.util.WeakHashMap;
import java.util.Map;
/** Hex grid view.
* Visualizes a {@link IHexGridModel}.
* @version 0.1, 03.06.2006
* @author Bjoern Wuest, Germany
public final class CHexGridView extends Canvas implements ComponentListener, IHexGridElementListener {
 /** Serial version unique identifier. */
 private static final long serialVersionUID = -965902826101261530L;
 /** Instance-constant parameter for the width of a hex grid element. */
 public final int CONST_Width;
 /** Instance-constant parameter for 1/4 of the width of a hex grid element. */
 public final int CONST_Width1fourth;
 /** Instance-constant parameter for 3/4 of the width of a hex grid element. */
 public final int CONST_Width3fourth;
 /** Instance-constant parameter for 1.5 times of the width of a hex grid element. */
 public final int CONST_Width1dot5;
 /** Instance-constant parameter for 4 times of the width of a hex grid element. */
 public final int CONST_Widthquad;
 /** Instance-constant parameter for the height of a hex grid element. */
 public final int CONST_Height;
 /** Instance-constant parameter for 1/2 of the height of a hex grid element. */
 public final int CONST_Heighthalf;
 /** Instance-constant parameter for the double height of a hex grid element. */
 public final int CONST_Heightdouble;
 /** The steepness of a side of the hex grid element (calculated for the upper left arc). */
 public final double CONST_Steepness;
 /** The model of this hex grid */
 private final IHexGridModel m_Model;
 /** A cache for already created images of the hex map. */
 private final Map<Point, Image> m_Cache = new WeakHashMap<Point, Image>();
 /** The graphical area to draw the selection ring around a hex element. */
 private final Area m_SelectionRing;
 /** The image of the selection ring around a hex element. */
 private final BufferedImage m_SelectionRingImage;
 /** The current position of the hex grid in pixels (top left visible corner). */
 private Point m_ScrollPosition = new Point(0, 0);
 /** Flag to define if a grid is shown ({@code true}) or not ({@code false}). */
 private boolean m_ShowGrid = true;
 /** Flag to define if the selected hex grid element should be highlighted ({@code true}) or not ({@code false}). */
 private boolean m_ShowSelected = true;
 /** The offset of hex grid elements shown on the screen, measured in hex grid elements. */
 private Point m_CurrentOffset = new Point(0, 0);
 /** The offset of the image shown on the screen, measured in pixels. */
 private Point m_PixelOffset = new Point(0, 0);
 /** The index of the currently selected hex grid element. */
 private Point m_CurrentSelected = new Point(0, 0);
 /** The width of a buffered pre-calculated image in pixel. */
 private int m_ImageWidth;
 /** The height of a buffered pre-calculated image in pixel. */
 private int m_ImageHeight;
 /** The maximum number of columns of hex grid elements to be shown at once on the screen. */
 private int m_MaxColumn;
 /** The maximum number of rows of hex grid elements to be shown at once on the screen. */
 private int m_MaxRow;
 /** Create a new hex grid view.
 * The hex grid view is bound to a {@link IHexGridModel} and registers at
 * that model to listen for {@link IHexGridElement} updates.
 * @param Model The model backing this view.
 public CHexGridView(IHexGridModel Model) {
 // Set the model
 m_Model = Model;
 CONST_Width = m_Model.getElementsWidth();
 CONST_Height = m_Model.getElementsHeight();
 CONST_Width1fourth = CONST_Width/4;
 CONST_Width3fourth = CONST_Width*3/4;
 CONST_Width1dot5 = CONST_Width*3/2;
 CONST_Heighthalf = CONST_Height/2;
 CONST_Widthquad = CONST_Width*4;
 CONST_Heightdouble = CONST_Height*2;
 CONST_Steepness = (double)CONST_Heighthalf / CONST_Width1fourth;
 m_ImageWidth = getSize().width+CONST_Widthquad;
 m_ImageHeight = getSize().height+CONST_Heightdouble;
 m_MaxColumn = m_ImageWidth / CONST_Width3fourth;
 m_MaxRow = m_ImageHeight / CONST_Height;
 // Register this canvas for various notifications
 m_Model.addElementListener(this);
 addComponentListener(this);
 // Create the selection ring to highlight hex grid elements
 m_SelectionRing = new Area(new Polygon(new int[]{-1, CONST_Width1fourth-1, CONST_Width3fourth+1, CONST_Width+1, CONST_Width3fourth+1, CONST_Width1fourth-1}, new int[]{CONST_Heighthalf, -1, -1, CONST_Heighthalf, CONST_Height+1, CONST_Height+1}, 6));
 m_SelectionRing.subtract(new Area(new Polygon(new int[]{2, CONST_Width1fourth+2, CONST_Width3fourth-2, CONST_Width-2, CONST_Width3fourth-2, CONST_Width1fourth+2}, new int[]{CONST_Heighthalf, 2, 2, CONST_Heighthalf, CONST_Height-2, CONST_Height-2}, 6)));
 m_SelectionRingImage = new BufferedImage(CONST_Width, CONST_Height, BufferedImage.TYPE_INT_ARGB);
 Graphics2D g = m_SelectionRingImage.createGraphics();
 g.setColor(Color.WHITE);
 g.fill(m_SelectionRing);
 @Override public synchronized void paint(Graphics g2) {
 // Caculate the offset of indexes to show
 int offsetX = 2 * (m_ScrollPosition.x / CONST_Width1dot5) - 2;
 int offsetY = (int)(Math.ceil(m_ScrollPosition.y / CONST_Height) - 1);
 m_CurrentOffset = new Point(offsetX, offsetY);
 // Check if the image is in the cache
 Image drawing = m_Cache.get(m_CurrentOffset);
 if (drawing == null) {
 // The image is not cached, so draw it
 drawing = new BufferedImage(m_ImageWidth, m_ImageHeight, BufferedImage.TYPE_INT_ARGB);
 Graphics2D g = ((BufferedImage)drawing).createGraphics();
 // Draw background
 g.setColor(Color.BLACK);
 g.fillRect(0, 0, m_ImageWidth, m_ImageHeight);
 // Draw the hex grid
 for (int column = 0; column <= m_MaxColumn; column += 2) {
 for (int row = 0; row <= m_MaxRow; row++) {
 // Draw even column
 IHexGridElement element = m_Model.getElementAt(offsetX + column, offsetY + row);
 if (element != null) { g.drawImage(element.getImage(m_ShowGrid), (int)(column*(CONST_Width3fourth-0.5)), CONST_Height*row, null); }
 // Draw odd column
 element = m_Model.getElementAt(offsetX + column+1, offsetY + row);
 if (element!= null) { g.drawImage(element.getImage(m_ShowGrid), (int)(column*(CONST_Width3fourth-0.5)+CONST_Width3fourth), CONST_Heighthalf*(row*2+1), null); }
 // Put the image into the cache
 m_Cache.put(m_CurrentOffset, drawing);
 // Calculate the position of the image to show
 offsetX = CONST_Width1dot5 + (m_ScrollPosition.x % CONST_Width1dot5);
 offsetY = CONST_Height + (m_ScrollPosition.y % CONST_Height);
 m_PixelOffset = new Point(offsetX, offsetY);
 g2.drawImage(drawing, -offsetX, -offsetY, null);
 // If the selected element should he highlighted, then do so
 if (m_ShowSelected) {
 // Check if the selected element is on screen
 if (isElementOnScreen(m_CurrentSelected)) {
 // Correct vertical offset for odd columns
 if ((m_CurrentSelected.x % 2 == 1)) { offsetY -= CONST_Heighthalf; }
 // Draw the selection circle
 g2.drawImage(m_SelectionRingImage, (m_CurrentSelected.x - m_CurrentOffset.x) * CONST_Width3fourth - offsetX - ((m_CurrentSelected.x + 1) / 2), (m_CurrentSelected.y - m_CurrentOffset.y) * CONST_Height - offsetY, null);
 @Override public synchronized void update(Graphics g) { paint(g); }
 public synchronized void componentResized(ComponentEvent e) {
 // Upon resizing of the component, adjust several pre-calculated values
 m_ImageWidth = getSize().width+CONST_Widthquad;
 m_ImageHeight = getSize().height+CONST_Heightdouble;
 m_MaxColumn = m_ImageWidth / CONST_Width3fourth;
 m_MaxRow = m_ImageHeight / CONST_Height;
 // And flush the cache
 m_Cache.clear();
 public void componentMoved(ComponentEvent e) { /* do nothing */ }
 public void componentShown(ComponentEvent e) { /* do nothing */ }
 public void componentHidden(ComponentEvent e) { /* do nothing */ }
 public synchronized void elementUpdated(IHexGridElement Element) {
 // Clear cache where the element may be contained at
 for (Point p : m_Cache.keySet()) { if (isElementInScope(Element.getIndex(), p, new Point(p.x + m_MaxColumn, p.y + m_MaxRow))) { m_Cache.remove(p); } }
 // Update the currently shown image if the update element is shown, too
 if (isElementOnScreen(Element.getIndex())) { repaint(); }
 /** Returns the model visualized by this grid view.
 * @return The model visualized by this grid view.
 public IHexGridModel getModel() { return m_Model; }
 /** Returns the current selected hex grid element.
 * @return The current selected hex grid element.
 public IHexGridElement getSelected() { return m_Model.getElementAt(m_CurrentSelected.x, m_CurrentSelected.y); }
 /** Sets the current selected hex grid element by its index.
 * If the selected hex grid element should be highlighted and is currently
 * shown on the screen, then this method will {@link #repaint() redraw} this
 * component automatically.
 * @param Index The index of the hex grid element to become the selected one.
 * @throws IllegalArgumentException If the index refers to a non-existing hex
 * grid element.
 public synchronized void setSelected(Point Index) throws IllegalArgumentException {
 // Check that the index is valid
 if ((Index.x < 0) || (Index.y < 0) || (Index.x > m_Model.getXElements()) || (Index.y > m_Model.getYElements())) { throw new IllegalArgumentException("There is no hex grid element with such index."); }
 m_CurrentSelected = Index;
 // If the element is on screen and should be highlighted, then repaint
 if (m_ShowSelected && isElementOnScreen(m_CurrentSelected)) { repaint(); }
 /** Moves the visible elements to the left by the number of pixels.
 * To move the visible elements to the left by one hex grid element, pass
 * {@link #CONST_Width3fourth} as the parameter. The component will
 * automatically {@link #repaint()}.
 * @param Pixels The number of pixels to move to the left.
 * @return The number of pixels moved to the left. This is always between 0
 * and {@code abs(Pixels)}.
 public synchronized int moveLeft(int Pixels) {
 int delta = m_ScrollPosition.x - Math.max(0, m_ScrollPosition.x - Math.max(0, Pixels));
 if (delta != 0) {
 m_ScrollPosition.x -= delta;
 repaint();
 return delta;
 /** Moves the visible elements up by the number of pixels.
 * To move the visible elements up by one hex grid element, pass {@link
 * #CONST_Height} as the parameter. The component will automatically {@link
 * #repaint()}.
 * @param Pixels The number of pixels to move up.
 * @return The number of pixels moved up. This is always between 0 and {@code
 * abs(Pixels)}.
 public synchronized int moveUp(int Pixels) {
 int delta = m_ScrollPosition.y - Math.max(0, m_ScrollPosition.y - Math.max(0, Pixels));
 if (delta != 0) {
 m_ScrollPosition.y -= delta;
 repaint();
 return delta;
 /** Moves the visible elements to the right by the number of pixels.
 * To move the visible elements to the right by one hex grid element, pass
 * {@link #CONST_Width3fourth} as the parameter. The component will
 * automatically {@link #repaint()}.
 * @param Pixels The number of pixels to move to the right.
 * @return The number of pixels moved to the right. This is always between 0
 * and {@code abs(Pixels)}.
 public synchronized int moveRight(int Pixels) {
 int delta = Math.min(m_Model.getXElements() * CONST_Width3fourth + CONST_Width1fourth - getSize().width, m_ScrollPosition.x + Math.max(0, Pixels)) - m_ScrollPosition.x;
 if (delta != 0) {
 m_ScrollPosition.x += delta;
 repaint();
 return delta;
 /** Moves the visible elements down by the number of pixels.
 * To move the visible elements down by one hex grid element, pass {@link
 * #CONST_Height} as the parameter. The component will automatically {@link
 * #repaint()}.
 * @param Pixels The number of pixels to move down.
 * @return The number of pixels moved down. This is always between 0 and
 * {@code abs(Pixels)}.
 public synchronized int moveDown(int Pixels) {
 int delta = Math.min(m_Model.getYElements() * CONST_Height + CONST_Heighthalf - getSize().height, m_ScrollPosition.y + Math.max(0, Pixels)) - m_ScrollPosition.y;
 if (delta != 0) {
 m_ScrollPosition.y += delta;
 repaint();
 return delta;
 /** Checks if the hex grid element of the given index is currently
 * displayed on the screen (even just one pixel).
 * The intention of this method is to check if a {@link #repaint()} is
 * necessary or not.
 * @param ElementIndex The index of the element to check.
 * @return {@code true} if the hex grid element of the given index is
 * displayed on the screen, {@code false} if not.
 public synchronized boolean isElementOnScreen(Point ElementIndex) { return isElementInScope(ElementIndex, m_CurrentOffset, new Point(m_CurrentOffset.x + m_MaxColumn, m_CurrentOffset.y + m_MaxRow)); }
 /** Checks if the hex grid element of the given index is within the given
 * indexes.
 * The intention of this method is to check if a {@link #repaint()} is
 * necessary or not.
 * @param ElementIndex The index of the element to check.
 * @param ReferenceIndexLeftTop The left top index of the area to check.
 * @param ReferenceIndexRightBottom The right bottom index of the area to check.
 * @return {@code true} if the hex grid element of the given index is within
 * the given area, {@code false} if not.
 public synchronized boolean isElementInScope(Point ElementIndex, Point ReferenceIndexLeftTop, Point ReferenceIndexRightBottom) { if ((ElementIndex.x >= ReferenceIndexLeftTop.x) && (ElementIndex.x <= ReferenceIndexRightBottom.x) && (ElementIndex.y >= ReferenceIndexLeftTop.y) && (ElementIndex.y <= (ReferenceIndexRightBottom.y))) { return true; } else { return false; } }
 /** Return the {@link IHexGridElement hex grid element} shown at the given
 * pixel on the screen.
 * Remark: There seems to be a bug in retrieving the proper element,
 * propably caused by rounding errors and unprecise pixel calculations.
 * @param P The pixel on the screen.
 * @return The {@link IHexGridElement hex grid element} shown at the pixel.
 public synchronized IHexGridElement getElementAtPixel(Point P) {
 // @FIXME Here seems to be some bugs remaining
 int dummy = 0; // Variable for warning to indicate that there is something to do :)
 // Calculate the pixel on the image, not on the screen
 int px = P.x + m_PixelOffset.x;
 int py = P.y + m_PixelOffset.y;
 // Determine the x-index of the column (is maybe decreased by one)
 int x = px / CONST_Width3fourth + m_CurrentOffset.x;
 // If the column is odd, then shift the y-pixel by half element height
 if ((x % 2) == 1) { py -= CONST_Heighthalf; }
 // Determine the y-index of the row (is maybe decreased by one)
 int y = py / CONST_Height + m_CurrentOffset.y;
 // Normative coordinates to a single element
 px -= (x - m_CurrentOffset.x) * CONST_Width3fourth;
 py -= (y - m_CurrentOffset.y) * CONST_Height;
 // Check if the normative pixel is in the first quarter of a column
 if (px < CONST_Width1fourth) {
 // Adjustments to the index may be necessary
 if (py < CONST_Heighthalf) {
 // We are in the upper half of a hex-element
 double ty = CONST_Heighthalf - CONST_Steepness * px;
 if (py < ty) { x--; }
 } else {
 // We are in the lower half of a hex-element
 double ty = CONST_Heighthalf + CONST_Steepness * px;
 if (py > ty) {
 x--;
 y++;
 return m_Model.getElementAt(x, y);
}Ah, just to give you some idea: I use this component to visualize a hex grid map with more than 1 million grid elements. And it works, really fast, and requires less than 10 MByte of memory.

Problem in java.awt.print

Hi here is my code .
I am generating page dynamically and passing to printer.
Printing Functionalities working file. But I am taking some data from database (Access). And in this code for example i have 4 records in Database and i am generating 4 pages (each page for resord).
I am getting only 2 records. And for other two records i am getting blank page.
Reason is My ResultSet object is moving to next record twice.
I mean if i have 6 records i get only 3 pages.
If i have 10 records i get only 5 pages and If i have 1 record i dont get any page.
How shall i solve this problem.
Thanx in advance.
import java.awt.*;
import java.awt.print.*;
import java.sql.*;
public class SubbuBook extends Thread implements Printable {
Connection con;
     Statement stmt;
     static ResultSet rsValue;
     public void run() {
          dataConnection();
          PrinterJob job = PrinterJob.getPrinterJob();
          Book bk = new Book();
          job.setPageable(bk);
          if (job.printDialog()) {
     try {
          bk.append(new SubbuBook(),job.defaultPage(), 4);
          job.print();
          }catch (Exception e) {
          System.out.println("Exception "+e);
     System.exit(0);
public int print(Graphics g, PageFormat pf, int pageIndex) throws PrinterException {
     Font fntHeading = new Font("Helvetica",Font.BOLD,24);
Font fntRow = new Font("Helvetica",Font.PLAIN,14);
     try{
     if(rsValue.next()) {
          g.setFont(fntHeading);
          g.setColor(Color.red);
          g.drawString("Main Report",200,100);
          g.setColor(Color.blue);
          g.drawLine(100,150,500,150);
          g.drawLine(100,150,100,500);
          g.drawLine(100,500,500,500);
          g.drawLine(500,100,500,500);
          g.drawLine(200,150,200,500);
          g.setFont(fntRow);
          g.setColor(Color.black);
          g.drawString("Program Id",120,200);
          g.drawString(rsValue.getString("prog_id"),250,200);
          g.drawString("Program Name",120,250);
          g.drawString(rsValue.getString("prog_name"),250,250);
          g.drawString("Artist Name",120,300);
          g.drawString(rsValue.getString("Artist"),250,300);
     }catch(Exception ae) {
     System.out.println("Exception inside Paint"+ae);
     return Printable.PAGE_EXISTS;
private void dataConnection() {
     try{
     Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
     con=DriverManager.getConnection("jdbc:odbc:artist");
     stmt=con.createStatement();
     rsValue=stmt.executeQuery("select * from artist order by Prog_name");
     System.out.println("Connection is Proper");
     }catch(Exception e){
          System.out.println("Exception at Connection"+e);

I am not sure this..
Instead of if pls give while and check:
try{
while(rsValue.next()) {
g.setFont(fntHeading);
g.setColor(Color.red);
g.drawString("Main Report",200,100);

Using of JLoox components in Swing/AWT Paint

I am facing problem in using JLoox components in Swing/AWT Paint method.I am able to use the JLoox components in Constructor of Swing JFrame and facing problem while using the JLoox components in Paint method.If anybody used JLoox please suggest the way to use it.

Yes I have used JLOOX since last 2 years.
There is a LxGraph derived from LxAbstract and LxView derived from LxAbstractView. This LxAbstractView is in turn derived from JComponent. LxGraph is a model for LxView (same apporch like MVC). You create components (i.e. LxRectangle, LxCircle, LxLine, LxLink, etc) and add it to either graph or in view). Finally this view (i.e. LxView) is added to a java container (JPanel, JScrollBar, etc.) You cannot pass JLoox component into JFrame constructor.
-regards,
Pratap

Can I draw *.bmp, *.png in java.awt.canvas ?

In paint method of my program, I get image from Toolkit like this:
public class CanCanvas extends Canvas{
//In loadImage method
Toolkit.getDefaultToolkit().getImage(
 getClass().getClassLoader().getResource(
 resource.getString("bg.jpg")));
//.... In paint method
if (image != null && image.size() > 0) {
 for (int j = 0; j < image.size(); j++) {
 Image image1 = (Image) image.elementAt(j);
 Rectangle rectangle = (Rectangle) imgLocation.elementAt(j);
 g.drawImage(image1, rectangle.x, offset + rectangle.y,
 rectangle.width, rectangle.height, null);
 i = i <= rectangle.y + rectangle.height + 7 ? rectangle.y
 + rectangle.height + 7 : i;But there is something very strange, if my image is *.jpg or *.gif, it runs ok, otherwise -*.bmp, *.png-, it can't draw the image.
Would anyone tell me why ? Is the reason java.awt.canvas ?
Thanks in advance ^ ^

If you'd bother to read the documentation of the methods you're using, you'd know:
http://java.sun.com/j2se/1.4.2/docs/api/java/awt/Toolkit.html#getImage(java.lang.String)
Returns an image which gets pixel data from the specified file, whose format can be either GIF, JPEG or PNG.

How to move image in Java Awt.

Hi ,
I am developing a simple application using Java awt.
I have created a application which displays a image. now i want it to move automatically using a timer or something.
How can i do it. if i have to change the x and y position of the image in which function should i do it?
Which is the function which is called for every frame?
Thanks
Glen.

public void paint(Graphics g)?
Are you making a game by any chance?

How can i display multiple Pictures in a java.awt.Container best?

hi,
I just started with a new Project, it works just like a FileManager.
On entering a directory all the files in it shall be displayed in a scrollable area. Displayed means here a Graphical representation of the file, in case of a picture a small preview version of it.
I put together a javax.swing.JScrollPane with a java.awt.Container and viewport. The Container has a FlowLayout.
Now for every image in a Directory I create a Component-class in witch I overwrote the public void paint(Graphics g) to display a scaled version of the image, this scaled version is created in the Constructor of my Component-class.
this works fine for just a few images, but if i try to open a directory with a lot of pictures it takes a long time at the beginning and sometimes it just kills the application.
so i changed in a way that only when a Component is in view of the visible rectangle of the scroll pane the scaled image will be created, and when the component gets out of view the image is set to null.
now it is running without killing the application, but it takes way too long to scroll now, because the images are loaded all the time.
so i figured i must be doing something wrong, so what is the best way to get small previews for up to a few hundred files and then display them in a scrollable area? (like in Windows Explorer if you activate the miniature preview)
if anyone can give me some hints, that would be great
thanks shirasuresh

This might give you some ideas:
import java.awt.*;
import javax.swing.*;
public abstract class LazyIcon implements Icon {
    private int width;
    private int height;
    private Image image;
    public LazyIcon(int width, int height) {
        this.width = width;
        this.height = height;
    protected abstract Image createImage();
    public int getIconHeight() {
        return width;
    public int getIconWidth() {
        return height;
    public void paintIcon(Component comp, Graphics g,int x, int y) {
        if (image == null)
            image = createImage();
        g.drawImage(image, x, y, comp);
}You could also do this with a custom component class, but I like the JLabel + Icon combination.
Any if you want to get fancy, you could load images in another thread, at low priority, so when the user is just sitting there, your code is preparing the panel for scrolling ;-)
Message was edited by:
BigDaddyLoveHandles

How can I create a java.awt.Image from ...

Hi all,
How can I create a java.awt.Image from a drawing on a JPanel?
Thanks.

JPanel p;
BufferedImage image =
new BufferedImage(p.getWidth(), p.getHeight, BufferedImage.TYPE_INT_RGB);
Graphics2D g = image.createGraphics();
p.paint(g);
g.dispose();

How to restrict the maximum size of a java.awt.ScrollPane

Dear all,
I would like to implement a scroll pane which is resizable, but not to a size exceeding the maximum size of the java.awt.Canvas that it contains.
I've sort of managed to do this by writing a subclass of java.awt.ScrollPane which implements java.awt.event.ComponentListener and has a componentResized method that checks whether the ScrollPane's viewport width (height) exceeds the content's preferred size, and if so, resizes the pane appropriately (see code below).
It seems to me, however, that there ought to be a simpler way to achieve this.
One slightly weird thing is that when the downsizing of the pane happens, the content can once be moved to the left by sliding the horizontal scrollbar, but not by clicking on the arrows. This causes one column of gray pixels to disappear and the rightmost column of the content to appear; subsequent actions on the scrollbar does not have any further effect. Likewise, the vertical scrollbar can also be moved up once.
Also, I would like a java.awt.Frame containing such a restrictedly resizable scrollpane, such that the Frame cannot be resized by the user such that its inside is larger than the maximum size of the scrollpane. The difficulty I encountered with that is that setSize on a Frame appears to set the size of the window including the decorations provided by the window manager (fvwm2, if that matters), and I haven't been able to find anything similar to getViewportSize, which would let me find out the size of the area inside the Frame which is available for the scrollpane which the frame contains.
Thanks in advance for hints and advice.
Here's the code of the componentResized method:
public void componentResized(java.awt.event.ComponentEvent e)
 java.awt.Dimension contentSize = this.content.getPreferredSize();
 this.content.setSize(contentSize);
 java.awt.Dimension viewportSize = getViewportSize();
 System.err.println("MaxSizeScrollPane: contentSize = " + contentSize);
 System.err.println("MaxSizeScrollPane: viewportSize = " + viewportSize);
 int dx = Math.max(0, (int) (viewportSize.getWidth() - contentSize.getWidth()));
 int dy = Math.max(0, (int) (viewportSize.getHeight() - contentSize.getHeight()));
 System.err.println("MaxSizeScrollPane: dx = " + dx + ", dy = " + dy);
 if ((dx > 0) || (dy > 0))
 java.awt.Dimension currentSize = getSize();
 System.err.println("MaxSizeScrollPane: currentSize = " + currentSize);
 setSize(new java.awt.Dimension(((int) currentSize.getWidth()) - dx, ((int) currentSize.getHeight()) - dy));
 System.err.println();
}Best regards, Jan

import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
public class ScrollPaneTest
 GraphicCanvas canvas;
 CustomScrollPane scrollPane;
 private Panel getScrollPanel()
 canvas = new GraphicCanvas();
 scrollPane = new CustomScrollPane();
 scrollPane.add(canvas);
 // GridBagLayout allows scrollPane to remain at
 // its preferred size during resizing activity
 Panel panel = new Panel(new GridBagLayout());
 GridBagConstraints gbc = new GridBagConstraints();
 panel.add(scrollPane, gbc);
 return panel;
 private WindowListener closer = new WindowAdapter()
 public void windowClosing(WindowEvent e)
 System.exit(0);
 private Panel getUIPanel()
 int w = canvas.width;
 int h = canvas.height;
 int visible = 100;
 int minimum = 200;
 int maximum = 500;
 final Scrollbar
 width = new Scrollbar(Scrollbar.HORIZONTAL, w,
 visible, minimum, maximum),
 height = new Scrollbar(Scrollbar.HORIZONTAL, h,
 visible, minimum, maximum);
 AdjustmentListener l = new AdjustmentListener()
 public void adjustmentValueChanged(AdjustmentEvent e)
 Scrollbar scrollbar = (Scrollbar)e.getSource();
 int value = scrollbar.getValue();
 if(scrollbar == width)
 canvas.setWidth(value);
 if(scrollbar == height)
 canvas.setHeight(value);
 canvas.invalidate();
 scrollPane.validate();
 width.addAdjustmentListener(l);
 height.addAdjustmentListener(l);
 Panel panel = new Panel(new GridBagLayout());
 GridBagConstraints gbc = new GridBagConstraints();
 gbc.insets = new Insets(2,2,2,2);
 gbc.weightx = 1.0;
 addComponents(new Label("width"), width, panel, gbc);
 addComponents(new Label("height"), height, panel, gbc);
 gbc.anchor = GridBagConstraints.CENTER;
 return panel;
 private void addComponents(Component c1, Component c2, Container c,
 GridBagConstraints gbc)
 gbc.anchor = GridBagConstraints.EAST;
 c.add(c1, gbc);
 gbc.anchor = GridBagConstraints.WEST;
 c.add(c2, gbc);
 public static void main(String[] args)
 ScrollPaneTest test = new ScrollPaneTest();
 Frame f = new Frame();
 f.addWindowListener(test.closer);
 f.add(test.getScrollPanel());
 f.add(test.getUIPanel(), "South");
 f.pack();
 f.setLocation(200,200);
 f.setVisible(true);
 f.addComponentListener(new FrameSizer(f));
class GraphicCanvas extends Canvas
 int width, height;
 public GraphicCanvas()
 width = 300;
 height = 300;
 public void paint(Graphics g)
 super.paint(g);
 Graphics2D g2 = (Graphics2D)g;
 g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
 RenderingHints.VALUE_ANTIALIAS_ON);
 int dia = Math.min(width, height)*7/8;
 g2.setPaint(Color.blue);
 g2.draw(new Rectangle2D.Double(width/16, height/16, width*7/8, height*7/8));
 g2.setPaint(Color.green.darker());
 g2.draw(new Ellipse2D.Double(width/2 - dia/2, height/2 - dia/2, dia-1, dia-1));
 g2.setPaint(Color.red);
 g2.draw(new Line2D.Double(width/16, height*15/16-1, width*15/16-1, height/16));
 public Dimension getPreferredSize()
 return new Dimension(width, height);
 public Dimension getMaximumSize()
 return getPreferredSize();
 public void setWidth(int w)
 width = w;
 repaint();
 public void setHeight(int h)
 height = h;
 repaint();
class CustomScrollPane extends ScrollPane
 Dimension minimumSize;
 public Dimension getPreferredSize()
 Component child = getComponent(0);
 if(child != null)
 Dimension d = child.getPreferredSize();
 if(minimumSize == null)
 minimumSize = (Dimension)d.clone();
 Insets insets = getInsets();
 d.width += insets.left + insets.right;
 d.height += insets.top + insets.bottom;
 return d;
 return null;
 public Dimension getMinimumSize()
 return minimumSize;
 public Dimension getMaximumSize()
 Component child = getComponent(0);
 if(child != null)
 return child.getMaximumSize();
 return null;
class FrameSizer extends ComponentAdapter
 Frame f;
 public FrameSizer(Frame f)
 this.f = f;
 public void componentResized(ComponentEvent e)
 Dimension needed = getSizeForViewport();
 Dimension size = f.getSize();
 if(size.width > needed.width || size.height > needed.height)
 f.setSize(needed);
 f.pack();
 * returns the minimum required frame size that will allow
 * the scrollPane to be displayed at its preferred size
 private Dimension getSizeForViewport()
 ScrollPane scrollPane = getScrollPane(f);
 Insets insets = f.getInsets();
 int w = scrollPane.getWidth() + insets.left + insets.right;
 int h = getHeightOfChildren() + insets.top + insets.bottom;
 return new Dimension(w, h);
 private ScrollPane getScrollPane(Container cont)
 Component[] c = cont.getComponents();
 for(int j = 0; j < c.length; j++)
 if(c[j] instanceof ScrollPane)
 return (ScrollPane)c[j];
 if(((Container)c[j]).getComponentCount() > 0)
 return getScrollPane((Container)c[j]);
 return null;
 private int getHeightOfChildren()
 Component[] c = f.getComponents();
 int extraHeight = 0;
 for(int j = 0; j < c.length; j++)
 int height;
 if(((Container)c[j]).getComponent(0) instanceof ScrollPane)
 height = ((Container)c[j]).getComponent(0).getHeight();
 else
 height = c[j].getHeight();
 extraHeight += height;
 return extraHeight;
}

Rendering of an 8Bit-tiff with java.awt produces crap

Hi Folks,
i do a downsampling of tiff images. The source tiffs are colored 8 Bit greyscale with a 256 color-table. Now i have 2 possibilities to resample with java.awt:
1. the target-tiff is of 24Bit true color:
BufferedImage objDownsample = new BufferedImage(iTargetWidth, iTargetHeight, BufferedImage.TYPE_INT_RGB);The result is a perfect looking, but oversized tiff with 16 million colors each pixel.
2. the target-tiff is of 8Bit like the source-tiff:
BufferedImage objDownsample = new BufferedImage(iTargetWidth, iTargetHeight, BufferedImage.TYPE_BYTE_INDEXED,(IndexColorModel)image.getColorModel());The result is a small sized tiff image of 8Bit. Problem: it now has visible vertical stripes of two colors (which both composed result the source-color i assume).
Does anybody know what's wrong here and how to retrieve the 8Bit color-image without stripes?
Here comes the whole source:
 private BufferedImage resize(int newHeight, int newWidth, BufferedImage image) {
 int iTargetHeight = newHeight;
 int iTargetWidth = newWidth;
 //Create a BufferedImage that fits
 BufferedImage objDownsample = new BufferedImage(iTargetWidth, iTargetHeight, BufferedImage.TYPE_BYTE_INDEXED,(IndexColorModel)image.getColorModel());
 //A map with all necessary rendering hints to optimize the quality of the image
 Map<java.awt.RenderingHints.Key, java.lang.Object> obj_Map = new HashMap<java.awt.RenderingHints.Key, java.lang.Object>();
 obj_Map.put(RenderingHints.KEY_DITHERING, RenderingHints.VALUE_DITHER_ENABLE);
 obj_Map.put(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
 obj_Map.put(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
 // Draw the scaled image
 Graphics2D graphics2D = objDownsample.createGraphics();
 graphics2D.addRenderingHints(obj_Map);
 graphics2D.drawImage(image, 0, 0, iTargetWidth, iTargetHeight, null);
 return objDownsample;
 }Thanks
Albrecht

As far as I can tell, this solution only allows compositing within the component that is currently being painted. What would be nice is if I could add a custom composite to say .. a JLabel, which paints based on the colors of the underlying pixel data (ie. from its parent container). In this way you could make a JLabel that always inverts the color of what's underneath.
Here, painting to the screen using a composite allows me to get the pixels underneath as the destination raster, the pixels in the JLabel as the source raster, and what actually gets painted which is the destination output raster.
If I paint to a BufferedImage instead, the composite's 'destination raster' is the new BufferedImage's default values which are all black. Thus compositing over this would not have the desired effects described above (inverting the underlying image for instance). The missing piece when rendering to the BufferedImage is first copying the underlying screen data into a BufferedImage before painting to it. How do I do that? Something tells me it's very difficult.

Cannot resolve symbol java.awt.graphics

// DrawRectangleDemo.java
import java.awt.*;
import java.lang.Object;
import java.applet.Applet;
public class DrawRectangleDemo extends Applet
 public void paint (Graphics g)
 // Get the height and width of the applet's drawing surface.
 int width = getSize ().width;
 int height = getSize ().height;
 int rectWidth = (width-50)/3;
 int rectHeight = (height-70)/2;
 int x = 5;
 int y = 5;
 g.drawRect (x, y, rectWidth, rectHeight);
 g.drawString ("drawRect", x, rectHeight + 30);
 x += rectWidth + 20;
 g.fillRect (x, y, rectWidth, rectHeight);
 // Calculate a border area with each side equal tp 25% of
 // the rectangle's width.
 int border = (int) (rectWidth * 0.25);
 // Clear 50% of the filled rectangle.
 g.clearRect (x + border, y + border,
 rectWidth - 2 * border, rectHeight - 2 * border);
 g.drawString ("fillRect/clearRect", x, rectHeight + 30);
 x += rectWidth + 20;
 g.drawRoundRect (x, y, rectWidth, rectHeight, 15, 15);
 g.drawString ("drawRoundRect", x, rectHeight + 30);
 x=5;
 y += rectHeight + 40;
 g.setColor (Color.yellow);
 for (int i = 0; i < 4; i++)
 g.draw3DRect (x + i * 2, y + i * 2,
 rectWidth - i * 4, rectHeight - i * 4, false);
 g.setColor (Color.black);
 g.drawString ("draw3DRect", x, y, + rectHeight + 25);
 x += rectWidth + 20;
 g.setColor (Color.yellow);
 g.fill3DRect (x, y, rectWidth, rectHeight, true);
 g.setColor (Color.black);
 g.drawString ("fill3DRect", x, y, + rectHeight + 25);
Help me with this codes. I typed correctly but there still errors.
--------------------Configuration: JDK version 1.3.1 <Default>--------------------
D:\Program Files\Xinox Software\JCreator LE\MyProjects\DrawRectangleDemo.java:56: cannot resolve symbol
symbol : method drawString (java.lang.String,int,int,int)
location: class java.awt.Graphics
 g.drawString ("draw3DRect", x, y, + rectHeight + 25);
^
D:\Program Files\Xinox Software\JCreator LE\MyProjects\DrawRectangleDemo.java:64: cannot resolve symbol
symbol : method drawString (java.lang.String,int,int,int)
location: class java.awt.Graphics
 g.drawString ("fill3DRect", x, y, + rectHeight + 25);
^
2 errors
Process completed.
-------------------------------------------------------------------------------------------------------------------------------

cannot resolve symbol
symbol : method drawString (java.lang.String,int,int,int)
This is telling you that you are trying to invoke the drawString() method with 4 parameters: String, int, int, int
If you look at the API the drawString() method need 3 parameters: String, int, int - so you have an extra int
location: class java.awt.Graphics
g.drawString ("draw3DRect", x, y, + rectHeight + 25);
Now is you look at your code you will find that you have 3 ',' in you method call. (I don't think you want the ',' after the y.

Can't find class when i use java.awt.Panel

I got a Pocket PC with CE 3.0
I made my first PJava application just a few hours ago. And it works fine. But when i introduce a Panel to improve the interface then application fails on the Pocket PC with the error message "could not find class application". When i remove the Panel it works fine again.
I thought that java.awt.* is part of PJava. And even if not i should be able to introduce even a java.lang.* class to the PJava application if i use the JAR.
Any suggestion?

you should provide more detail about your deployment procedures.
There are many ways to get this message. AWT in fact is part of pJava and works fine for most of us. So I assume the deployment is the problem. Have you checked the actual content of the JAR? Have you provided a path statement? How do you call your app (shortcut?)

Painters (java.awt.Paint interface)

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