Christopher, Thank you for a very informative reply.
I have another question that I hope you will be able to answer. PJA is one of the replacement toolkits: "100% Pure Java and doesn't use any native graphics resource". According to their website (http://www.eteks.com/pja/en/), "When no X11 Display is available on a UNIX machine (also called headless environment) or when GDI resources are low on Windows, it is impossible to compute off-screen images with java.awt.Graphics methods under a JDK version < 1.4, even if your program doesn't need to display these images. Typically, this situation happens for servlets returning dynamically generated images like pies, charts or web counters." I also read through the information from Sun (docs/guide/awt/AWTChanges.html) Am I correct in assuming that if I run J2SE 1.4 with "-Djava.awt.headless=true", native graphics resource will not be used and I will get a pure Java implementation just as if I was running one of the replacement toolkits? Thanks. Mike --- "Christopher K. St. John" <[EMAIL PROTECTED]> wrote: > Mike Duffy wrote: > > > > Is there a problem using running AWT classes on an > > application server? > > > > I'm assuming you mean using the AWT in headless mode > by setting "-Djava.awt.headless=true"? It works, but > you can't use most of the heavyweight components, > like Frames. You'll get an "java.awt.HeadlessException" > You can use code like this, though: > > BufferedImage bi = new > BufferedImage(128,128,BufferedImage.TYPE_INT_RGB); > Graphics2D g = bi.createGraphics(); > g.drawLine(0, 0, 120, 120); > Raster r = bi.getData(); > rsp.setContentType("image/jpeg"); > JPEGImageEncoder ie = > JPEGCodec.createJPEGEncoder(rsp.getOutputStream()); > ie.encode(bi); > > where "rsp" is the servlet response argument in doGet() > or doPost(). There's documentation in the JDK 1.4 > doc bundle: > > docs/guide/awt/AWTChanges.html > > If you're stuck with legacy code that uses heavyweight > components, you'll still need to run xvfb or use one > of the AWT replacement toolkits (check the list archives > for details, a search on "xvfb" will get you the > relevant threads) > > Or do you mean something completely different? > > > -- > Christopher St. John [EMAIL PROTECTED] > DistribuTopia http://www.distributopia.com > > ___________________________________________________________________________ > To unsubscribe, send email to [EMAIL PROTECTED] and include in > the body > of the message "signoff SERVLET-INTEREST". > > Archives: > http://archives.java.sun.com/archives/servlet-interest.html > Resources: > http://java.sun.com/products/servlet/external-resources.html > LISTSERV Help: http://www.lsoft.com/manuals/user/user.html > __________________________________________________ Do You Yahoo!? Yahoo! Tax Center - online filing with TurboTax http://taxes.yahoo.com/ ___________________________________________________________________________ To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff SERVLET-INTEREST". Archives: http://archives.java.sun.com/archives/servlet-interest.html Resources: http://java.sun.com/products/servlet/external-resources.html LISTSERV Help: http://www.lsoft.com/manuals/user/user.html
