不懂，前面看了sun的网站也是这样写的http://java.sun.com/products/java-media/2D/reference/faqs/index.htmlQ: I have an application that reads, writes, and processes images (but does not display them) using Java2D. When I run my application on Solaris or Linux, it complains that X11 is not available. What can I do to make my application work in this environment? A: When AWT is initialized, it expects to find an Xserver, regardless of whether it is needed for actual display. Although many image operations using the Image I/O APIs or the JAI optional package might not have any obvious need for display, they often invoke code that needs an AWT resource. For example, calling getGraphics() on a BufferedImage initializes AWT and causes these error messages seen by developers. There is no way to say that a particular API does or does not have this problem; it depends on what particular operations are being invoked, and might also depend on what the application does with the images that is not strictly related to any of the APIs cited above. There are two possible solutions. As of J2SE 1.4 (and above), the preferred solution is to use the "headless AWT toolkit". This feature allows you to use the Java2D API in a server-side application without the need for a display environment. To specify the headless environment, run your application with the following system property: -Djava.awt.headless=true For releases prior to J2SE 1.4 you can provide a "pseudo X-server" to emulate a display environment. One of these Xserver emulators is Xvfb, available for download at http://www.x.org. Another possibility is to start a VNC server (http://www.realvnc.com) and then run your application in that environment. Xvfb does still have one possible use in J2SE 1.4: A server application may need to display to an Xserver, but requires no user interaction. The headless toolkit won't support this situation, but xvfb will. This is a completely hypothetical scenario and it is not clear if any real world application exhibits such a behavior.
我不知道那个java-imaging-utilities底层是怎么实现的。
A: When AWT is initialized, it expects to find an Xserver, regardless of whether it is needed for actual display.
Although many image operations using the Image I/O APIs or the JAI optional package might not have any obvious need for display, they often invoke code that needs an AWT resource. For example, calling getGraphics() on a BufferedImage initializes AWT and causes these error messages seen by developers. There is no way to say that a particular API does or does not have this problem; it depends on what particular operations are being invoked, and might also depend on what the application does with the images that is not strictly related to any of the APIs cited above. There are two possible solutions. As of J2SE 1.4 (and above), the preferred solution is to use the "headless AWT toolkit". This feature allows you to use the Java2D API in a server-side application without the need for a display environment. To specify the headless environment, run your application with the following system property:
-Djava.awt.headless=true
For releases prior to J2SE 1.4 you can provide a "pseudo X-server" to emulate a display environment. One of these Xserver emulators is Xvfb, available for download at http://www.x.org. Another possibility is to start a VNC server (http://www.realvnc.com) and then run your application in that environment. Xvfb does still have one possible use in J2SE 1.4: A server application may need to display to an Xserver, but requires no user interaction. The headless toolkit won't support this situation, but xvfb will. This is a completely hypothetical scenario and it is not clear if any real world application exhibits such a behavior.