Java.awt issue in frame.addnotify()

Hi,
Iam new to awt's & many thanks if someone can help me to resolve the below issue.
The below method is called from a servlet & the expected output is a graphical report in the browser.
public void draw()
System.out.println("before Image");
setMAXMISSES();
System.out.println("before Image 1");
frame.setBackground(Color.lightGray);
System.out.println("before Image 2");
frame.setForeground(Color.black);
System.out.println("before Image 3");
frame.setSize(WIDTH,HEIGHT);
System.out.println("before Image 4");
frame.addNotify();
System.out.println("before Image 5");
When I executed the above code ,iam able to see the following in the logs:
before Image
before Image 1
before Image 2
before Image 3
before Image 4
Next to that there is no error/exception but the processing gets stuck up here & the frame.addnotify() method doesn't get executed & we get "page cannot be displayed error " in the browser.
Can anyone suggest & help me out.
Thanks ,
Satchin.

I don't know about swing, but you can try using AWT and compile it with J2SE (set compliance to 1.4). The jar file should work on your mobile device with Personal Profile.

Similar Messages

Very simple Java AWT Frame resize question

In the following code, I create an awt Frame. Unfortunately, when I run the resulting Java application (on Windows) and use the mouse to resize the window, none of the Frame's resize/setSize methods get called. Can anyone explain why this is?
Thanks
Greg
import java.awt.* ;
public class Junk extends Frame {
public static void main (String args[])
Junk j = new Junk ();
j.show ();
public void resize(Dimension arg0)
super.resize(arg0);
public void resize(int arg0, int arg1)
super.resize(arg0, arg1);
public void setSize(Dimension arg0)
super.setSize(arg0);
public void setSize(int arg0, int arg1)
super.setSize(arg0, arg1);
}

When the user resizes the frame with the mouse, the resizing action probably happens entirely on the Frame's peer, without the java.awt.Frame getting involved at all. setSize() and [deprecated] resize() allow an application to programmatically change the size of a Frame, but the Frame just passes the new size to its peer.
If you want to detect when your Frame has been resized, use addComponentListener to register a component listener on the Frame, and then put your code in the componentResized method of the listener.

Deprecation warning for getFontMetrics(java.awt.Font) in java.awt.Toolkit

Hi all,
When I use the following code
JComponent c;
FontMetrics metrics = getToolkit().getFontMetrics(c.getFont());
I get this following warning during compilation:-
warning: getFontMetrics(java.awt.Font) in java.awt.Toolkit has been deprecated
JDK suggests to use getLineMetrics() of the Font class.
But there's an issue with that: if I use getLineMetrics(), there is no API method that I can use to get the width of a string as opposed to FontMetrics which provides stringWidth(String str) method for that purpose. In fact all the methods in FontMetrics are not mapped into LineMetrics.
Could anyone please help or provide me at least some pointers on how to tackle this issue so that I can get rid of the deprecated method along with the existing methods mapped to equivalent APIs? The bottomline is that I should be able to maintain the existing functinality of my application for those part of code that uses getToolkit().getFontMetrics().
Thank you for your help in advance.
-Sanjoy Das

Use Graphics.getFontMetrics(font) instead.
After creation your frame and calling frame.show();
You can access it like that
frame.show();
frame.getGraphics().getFontMetrics(new Font("Arial",0,10));
before showing graphics is null.
Or just create a BufferedImage and ask it for graphics.
BufferedImage img=new BufferedImage(...);
img.getGraphics().getFontMetrics(font);
regards
Stas

Can I build a GUI application with SWING only without [import java.awt.*;]

I have seen several threads (in forums), books and tutorials about SWING and I see that they all mix SWING with AWT (I mean they import both Swing and AWT in their code).
The conclusion that comes out is:
It is good to learn about SWING and forget AWT as it won't be supported later. I have decided to do so, and I never include <<import java.awt.*;>> in my code.
But I see that you cannot do much without <<import java.awt.*;>>. For example this line which changes the background color:
<<frame.getContentPane().setBackground(Color.red)>>
works only with <<import java.awt.*;>>. I have seen that codes in this and other forums import awt to change the background. Why is that?
After all, I wonder, what can I do;
My question is, can I change the background (and of course do all other things listener, buttons etc) without using <<import java.awt.*;>>.
I would like to avoid using <<import java.awt.*;>> and using awt since my program will not work later.
In addition, I believe there is no point to learn awt, which later will not exist.
I know, I must have misunderstood something. I would appreceate it very much, if anyone could give me even a short answer.
Thank you in advance,
JMelsi

Since swing is a layer on top of awt, AWT will exist for as long as swing does.
If sun does ever remove AWT they will have to replace it something else swing can layer on to and you will probably only have to replace your import statements.
The main difference is the way there drawn to the screen.
You can do custom drawing on swing components but you can't on AWT.
If your using a desktop PC system it's probably best to use swing just in case you wish to do some custom drawing.
awt uses less memory than swing and is faster but swing can be extended. awt comes only as standard.
Say for example you wish to implement a JButton with a ProgressBar below the button text, this can be done with swing!

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.

Useless code in java.awt.image.SampleModel.java?

Hey there,
i just looked up the sourcecode of java.awt.image.SampleModel.java in JDK 6
I discovered two issues i'd like to discuss.
1) on lines 736 to 739 this code is stated:
if (iArray != null)
pixels = iArray;
else
pixels = new int[numBands * w * h];
I asked myself, why does this code exist? while the getPixels() method is overwritten twice by double[] getPixels() and float[] getPixels, it is impossible to reach the part of the java code that initializes the pixels-array. One could only step into that line if "null" is given for the i/d/fArray-parameter. but if one would do so, the Java parser couldn't determine, which method is to use. so this part of code is just useless IMHO.
the java developers could get a little more performance out of this method if the if statement would be cut out - especially when reading a lot of very small rasters
or, on the other hand, they could replace this piece of code by an explicit bounds check.
When somebody touches this code, i would appreciate it if the errormessage "index out of bounds!" could be rewritten to be a little more verbose, like: Index out of bounds(x=123; y=456, maxX=100, maxY=400)!(numbers are just examples)
I hope i didn't miss something very basic and could help improving this class a little bit.
2) the local variable Offset(line 734) is coded against code conventions which say, variables shall start with a lowercase letter. Offset obviously doesn't fit that convention.
best regards
kdot

One could only step into that line if "null" is given for the i/d/fArray-parameter. but if one would do so, the Java parser couldn't determine, which method is to use. so this part of code is just useless IMHO. You can have
sampleModel.getPixels(x,y,w,h,(int[]) null, dataBuffer);No ambiguity on which method to use.
the local variable Offset(line 734) is coded against code conventions which say, variables shall start with a lowercase letter. Offset obviously doesn't fit that convention. You're correct, offset is against coding conventions. So are many other examples scattered throughout the jdk source code. For example, Hashtable should be called HashTable. In some cases the coding conventions might not have been established when the original code was written. In other cases it might have been human error. In yet other cases the conventions were probably ignored. The person who wrote the SampleModel class did so some 10+ years ago (Java 1.2). Who knows what he/she was thinking at the time, and in all honesty - does it really matter in this case?
Did you know there are some classes that declare unused local variables (ahem ColorConvertOp)? Some also have unused imports ( *** cough *** BufferedImage *** cough *** ). In essence, the jdk source code is not the epidemy of code correctness. But it's still pretty good.

Java.awt.Dialog in Java 1.6 has a memory leak

When a modal Dialog opens a modal sub-dialog, the Dialog stays in memory after both the sub-dialog and the Dialog itself is disposed.
The field that contains the leaked object is Dialog.modalDialogs (static). The methods which causes the leak are Dialog.modalHide and Dialog.modalShow.
Whenever a modal Dialog is opened, Dialog.modalShow is called, and adds itself to Dialog.modalDialogs.
When it closes, Dialog.modalHide is called and removes one copy of itself from Dialog.modalDialogs. Then Dialog.modalShow is called on all previously blocked modal dialogs. When the sub-dialog is opened and closed, Dialog.modalDialogs contains two references to the main Dialog, and only one of them is removed when Dialog.modalHide for that Dialog is called.
To detect the leak, just put a break point in Dialog.modalHide, after modalDialogs.remove(this);. When opening a Dialog and closing it without opening a sub-dialog, the Dialog.modalDialogs field should be empty. When a sub-dialog was opened and closed before the main Dialog is closed, the Dialog.modalDialogs field contains a reference to the disposed main Dialog.
This leak does not exist in 1.5.0_10 (no Dialog.modalDialogs field). I have searched the bug database, but I have not found this bug there. Could anyone confirm this?
A simple code to reproduce the leak:
import java.awt.Dimension;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowEvent;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
public class Test {
   public static void main(String[] args) {
      final JFrame frame = new JFrame() {
         protected void processWindowEvent(WindowEvent e) {
            super.processWindowEvent(e);
            if (e.getID() == WindowEvent.WINDOW_CLOSING) {
               System.exit(0);
      JButton button = new JButton("Dialog");
      button.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent aE) {
            JButton subButton = new JButton("SubDialog");
            subButton.addActionListener(new ActionListener() {
               public void actionPerformed(ActionEvent aE) {
                  JOptionPane.showMessageDialog(frame, "SubDialog");
            JOptionPane.showMessageDialog(frame, subButton);
      frame.getContentPane().add(button);
      frame.pack();
      // Center the window
      Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
      Dimension frameSize = frame.getSize();
      if (frameSize.height > screenSize.height) {
         frameSize.height = screenSize.height;
      if (frameSize.width > screenSize.width) {
         frameSize.width = screenSize.width;
      frame.setLocation((screenSize.width - frameSize.width) / 2,
            (screenSize.height - frameSize.height) / 2);
      frame.setVisible(true);
}

Sorry, I just found the bug in the bugdatabase (with google of course,):
[http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6497929]

Java.awt.createFont(...) in Applet

I'm trying to dynamically load a truetype-font in an applet with Font.createFont(...) .
Unfortunately I'm always getting
java.lang.SecurityException: Unable to create temporary fileAnd, surprise, surprise, Font.createFont() requires a temporary file wich I found not to be documented in javadoc but in the source of Font.java (see last line of the next code example):
public static Font createFont ( int fontFormat, InputStream fontStream )
      throws java.awt.FontFormatException, java.io.IOException {
      if ( fontFormat != Font.TRUETYPE_FONT ) {
          throw new IllegalArgumentException ( "font format not recognized" );
      File fontFile = null;
      fontFile = File.createTempFile ( "font", ".ttf", null );Has anybody faced the same problem or an idea of how to solve this issue with little additional work?

has really nobody got an idea?

Java.awt.IllegalComponentStateException in JTable

Hi folks,
I am trying to write a JTable cell validation. Input data in a cell, if failure, prompt message and set focus & editing back to the cell. I've tried InputVerifier() but it doesn't work since I can easily use the mouse click to shift to other cells in the same table.
What I am trying to do now is to define my DefaultCellEditor. I record the row & index position when getting focus. In the lost focus event, do the validation and set the focus & editing back if failure. Seems it works fine. However, when I randomly click different cells in the table quickly. It prompts:
"java.awt.IllegalComponentStateException: component must be showing on the screen to determine its location"
Here is my stack dump:
     at java.awt.Component.getLocationOnScreen_NoTreeLock(Component.java:1487)
     at java.awt.Component.getLocationOnScreen(Component.java:1461)
     at javax.swing.Autoscroller.mouseDragged(Autoscroller.java:79)
     at javax.swing.JComponent.processMouseMotionEvent(JComponent.java:2759)
     at java.awt.Component.processEvent(Component.java:4822)
     at java.awt.Container.processEvent(Container.java:1525)
     at java.awt.Component.dispatchEventImpl(Component.java:3526)
     at java.awt.Container.dispatchEventImpl(Container.java:1582)
     at java.awt.Component.dispatchEvent(Component.java:3367)
     at javax.swing.plaf.basic.BasicTableUI$MouseInputHandler.repostEvent(BasicTableUI.java:475)
     at javax.swing.plaf.basic.BasicTableUI$MouseInputHandler.mouseDragged(BasicTableUI.java:554)
     at java.awt.AWTEventMulticaster.mouseDragged(AWTEventMulticaster.java:258)
     at java.awt.AWTEventMulticaster.mouseDragged(AWTEventMulticaster.java:257)
     at java.awt.AWTEventMulticaster.mouseDragged(AWTEventMulticaster.java:257)
     at java.awt.Component.processMouseMotionEvent(Component.java:5069)
     at javax.swing.JComponent.processMouseMotionEvent(JComponent.java:2763)
     at java.awt.Component.processEvent(Component.java:4822)
     at java.awt.Container.processEvent(Container.java:1525)
     at java.awt.Component.dispatchEventImpl(Component.java:3526)
     at java.awt.Container.dispatchEventImpl(Container.java:1582)
     at java.awt.Component.dispatchEvent(Component.java:3367)
     at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:3359)
     at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3091)
     at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3004)
     at java.awt.Container.dispatchEventImpl(Container.java:1568)
     at java.awt.Window.dispatchEventImpl(Window.java:1581)
     at java.awt.Component.dispatchEvent(Component.java:3367)
     at java.awt.EventQueue.dispatchEvent(EventQueue.java:445)
     at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:191)
     at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:144)
     at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
     at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:130)
     at java.awt.EventDispatchThread.run(EventDispatchThread.java:98)
Also, enclosed is my modified DefaultCellEditor class. Your input will be greatly appreicated. Thanks.
class NewDefaultCellEditor extends DefaultCellEditor {
public NewDefaultCellEditor(JTextField jTextField) {
super(jTextField);
this.setClickCountToStart(1);
jTextField.addFocusListener(new FocusAdapter() {
JTable tbl;
int row;
int column;
public void focusGained(FocusEvent e) {
tbl = (JTable)((JTextField)e.getSource()).getParent();
row = tbl.getEditingRow();
column = tbl.getEditingColumn();
public void focusLost(FocusEvent e) {
/*** Put validation here, execute the following if failed ***/
tbl.editCellAt(row, column);
((JTextField)e.getSource()).requestFocus();

Your use in a JTable isn't too clear to me, but I feel you're overthinking the basic requirement:
I have an extended JComboBox which is meant to display its information only. Thus it
- does not allow any selection
- shows the first item of the list in the TextField only and not once more in the listI don't see the need for duplicating the model and using a popup menu listener.
import java.awt.Component;
import javax.swing.*;
public class DisplayOnlyComboBoxDemo {
public static void main(String[] args) throws Exception {
    SwingUtilities.invokeLater(new Runnable() {
      @Override
      public void run() {
        new DisplayOnlyComboBoxDemo().makeUI();
public void makeUI() {
    JFrame frame = new JFrame();
    frame.add(new DisplayOnlyComboBox("One", new String[]{"Two", "Three", "Four", "Five"}));
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.pack();
    frame.setLocationRelativeTo(null);
    frame.setVisible(true);
class DisplayOnlyComboBox extends JComboBox {
private String firstItem;
public DisplayOnlyComboBox(String firstItem, String[] items) {
    super(items);
    this.firstItem = firstItem;
    setRenderer(new DefaultListCellRenderer() {
      @Override
      public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
        super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
        if (index == -1) {
          setText(DisplayOnlyComboBox.this.firstItem);
        return this;
}db

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?

Java.awt.Container.add(Container.java:345) how can i handle this

dear all,
i want to design an outlook for a chat applet. but this seems to tough as i am getting a run time error
my code is:
import java.awt.*;
import java.awt.event.*;
import java.net.*;
import java.io.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.net.*;
import java.io.*;
import javax.swing.*;
* the import that are required for this class
public class outer extends Frame //implements ActionListener, Runnable
private TextField txtusername,txtpassword,txtroomname;
private Label lblusername,lblpassword,lblroomname,lbllistofrooms;
Button okBtn,exitBut;
Color backColor=null,btnBackClr=null,btnForeClr=null;
String[] roomsavailable = {" one ", " two ", " three", " four"};
private JList rooms = new JList(roomsavailable);
/** the costructor*/
public outer()
{ // super(st);
backColor=new Color(200,200,255);
btnBackClr=new Color(225,240,255);
btnForeClr=new Color(205,205,205);
setBackground(backColor);
setLayout(null);
lblusername = new Label("Username");
lblusername.reshape(insets().left+5,insets().top+10,60,20);
add(lblusername);
txtusername=new TextField();
txtusername.reshape(insets().left+75,insets().top+10,60,20);
add(txtusername);
lblpassword = new Label("Password");
lblpassword.reshape(insets().left+5,insets().top+30,60,20);
add(lblpassword);
txtpassword=new TextField();
txtpassword.reshape(insets().left+75,insets().top+30,60,20);
add(txtpassword);
lblroomname = new Label("Select Room");
lblroomname.reshape(insets().left+5,insets().top+50,60,20);
add(lblroomname);
txtroomname=new TextField();
txtroomname.reshape(insets().left+75,insets().top+50,60,20);
add(txtroomname);
okBtn=new Button("Login");
okBtn.reshape(insets().left+25,insets().top+80,60,20);
add(okBtn);
// okBtn.addActionListener(this);
exitBut=new Button("EXIT");
exitBut.reshape(insets().left+50,insets().top+80,60,20);
add(exitBut);
// exitBut.addActionListener(this);
public static void main(String[] args)
// Create a JFrame
JFrame frame = new JFrame("client side");
// Create a outer class object
outer outerobj = new outer();
// Add the outer to the JFrame
frame.getContentPane().add(outerobj, BorderLayout.WEST);
// Set Jframe size
frame.setSize(800, 400);
//set resizable true
frame.setResizable(true);
// Set JFrame to visible
frame.setVisible(true);
// set the close operation so that the Application terminates when closed
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
when i compile it it compiles but gives run time error like this
RUN TIME error:
Exception in thread "main" java.lang.IllegalArgumentException: adding a window
to a container
at java.awt.Container.addImpl(Container.java:434)
at java.awt.Container.add(Container.java:345)
at outer.main(outer.java:75)
Press any key to continue...
i know erroe in this line
frame.getContentPane().add(outerobj, BorderLayout.WEST);
but how shall i add to get the proper layout by getting benifit of insets method
reply soon
please

You can't add a frame to a frame.
Try chaing the class definition from
public class outer extends Frameto
public class outer extends PanelPlease note to format your code (you'll get a faster response) use [ code]
Object names should always start with a capital letter. outer --> Outer

Java 7 update 51 cause the following error: java.util.HashMap cannot be cast to java.awt.RenderingHints

Since I installed Java 7 update 51 accessing the EMC VNX Unisphere Console cause the following error: java.util.HashMap cannot be cast to java.awt.RenderingHints.
I rolled back to Apple Java 1.6 -005 now I am getting the following error: plug-in failure.
I think this is cused by the fact that the EMC console application has been written for java 7 and not java 6. Has anybody faced and solved the "java.util.HashMap cannot be cast to java.awt.RenderingHints." error ?

Hi Yaakov,
The error is thrown from the eclipselink.jar:2.5.1 which is a JPA provider .
Is the above jar bundled in the Oracle Product you are working upon or was this downloaded from external site ?
If the jar is bundled with the Oracle Product, go ahead a log a SR with Oracle Support with Toplink product group to drill down on the issue, as the issue is happening internally or thrown by the Eclipselink implementation and we've no control....
Hope it helps!!
Thanks,
Vijaya

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;
}

Java.awt availability in CDC Toolkit ?

Hi guys and girls,
I've just tried out the Sun Java Toolkit for CDC 1.0 .. I tried making a simple app which uses awt components, such as Frame, Label, Button .. but the Label and Button just wont compile. I always thought that CDC has all the lib for the j2se's java.awt.
Quoted from CDC FAQ :
CDC currently supports three profiles. Foundation Profile provides basic application support APIs without any additional support for GUIs. Personal Basis Profile includes all of the APIs contained in Foundation Profile and adds support for lightweight AWT GUI components and the xlet application model. Personal Profile includes all of the APIs contained in Personal Basis Profile and adds support for full AWT compatibility and the applet application model.
Do i miss something .. ? Please help pointing out for me ..
I understand that there's swing from the AGui. So i tried making a new project with a simple class containing a simple JFrame, containing a JPanel which contains a button, which can be clicked to trigger a message type JOptionPane. But when the JOptionPane appears, it fills up the entire screen, i dont quite understand what is wrong.
Here's the code :
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class HelloWorld {
      * @param args
     public static void main(String[] args) {
          final JFrame frame = new JFrame("Ahiak");
          final JPanel panel = new JPanel(new FlowLayout());
          JButton but = new JButton("Click Me !");
          panel.add(but);
          frame.getContentPane().add(panel);
          but.addActionListener(new ActionListener() {
               public void actionPerformed(ActionEvent e) {
                    JOptionPane.showMessageDialog(panel, "hahah !");
          frame.setVisible(true);
}Please show some compassion and click the reply button, lol -_-

I don't know about swing, but you can try using AWT and compile it with J2SE (set compliance to 1.4). The jar file should work on your mobile device with Personal Profile.

Extends.java.awt.Window

Hi I've tried the following below (/** My Code **/) and get a compilation error: Window is not public in java.awt.Window; cannot be accessed from outside package.
I did set the JDK1.4 path in the autoexec.bat. The API 1.4 describes Window like:
public class Window
extends Container
/** My Code **/
import java.awt.*;
class WarningWindow extends Window
/** With the below code everything compiles **/
import java.awt.*;
class WarningWindow extends Container
/** END My Code **/
Can someone please tell me why I get this above error and how can I manage to import the Window class.
Thank You
L

Hello,
The problem is that Window constructor is not declared as public.
But i don't know why JDK1.4 refuse that.
By setting "package java.awt;" you'll access all these method but that is NOT a good solution (you should use Dialog, Frame or Container).
But there is still something strange... Why JDK1.4 refuses compiling that ??????

Java.awt issue in frame.addnotify()

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