=====FAQ===== **1. Can I use the Java-Editor in teaching at school? Can my pupils use it at home?**\\ Yes, the Java-Editor is freeware, especially developed for teaching purposes. **2. Is it possible to execute Java programs with the Java-Editor?**\\ Yes, of course, but the Java JDK has to be installed on your system. **3. If I compile a Java file test.java, the file test.class is generated, but also a file test$.class. Is this a temporary file which I can delete?**\\ The event methods in GUI programs use anonymous classes. For these classes, the compiler creates separate class files with the $ in the name which are necessary to execute the Java program. **4. Is it possible to separate Java files from class files?**\\ Yes, add //-d // as a [[Configuration#compiler|compiler parameter]]. Your class files will then be placed in the specified directory. For the Java interpreter to find the class files, you must also add the directory in the //Classpath-User// of the [[Configuration#interpreter|interpreter]] configuration. **5. Which access rights does the Java-Editor require?**\\ It needs write permissions in the folders where your Java source files are located, and in the [[Configuration#options|temporary files folder]]. **6. Is the Java-Editor network-compatible?**\\ The Java-Editor supports local drives, network drives and the UNC notation for direct network access, e. g. %%\\server\folder\program.java%%. This applies to Java files, the documentation files, and the entire JDK. **7. Can the Java-Editor be installed on a server?**\\ Yes, this is my preferred installation for using it in a classroom. The JDK is installed on each computer, but the Java-Editor is only installed on the server. This way it is convenient to update to a new Java-Editor version, as only the server must be modified. **8. Where does the Java-Editor store configuration data?**\\ During the installation, you decide whether the Java-Editor uses ini-files or the windows registry for configuration data. The configuration in the [[Configuration#Java|Java section]] is protected. It is stored in the HKEY_LOCAL_MACHINE\Software\JavaEditor hive of the registry or in the file JEMachine.ini. User-specific settings are stored separately for each user in the hive KEY_CURRENT_USER\Software\JavaEditor or in the file JEUser.ini. The //Dump// button in the configuration window opens a text file which contains the current storage locations. The Java-Editor looks after a file JEMachine.INI in its folder. If this file exists, it uses ini files, otherwise it uses the windos registry to store configuration data. **9. My Java program doesn't start. What can I do?**\\ If your Java program is compiled without errors but your program does not start, it is likely that runtime errors occur during the execution. You can use the //RunJava.bat// file for further analysing the problem. Open the [[Configuration#interpreter|interpreter]] configuration and click on //RunJava.bat// to edit the batch file which is used to start your Java program. Replace //@ECHO OFF// with //@ECHO ON// and insert PAUSE at the end of the file. Save the modified //RunJava.bat// and select //DOS Window// from the [[:start#window_menu|window menu]]. This opens a console window with the folder of RunJava.bat as current folder. Type in RunJava.bat and analyse the error messages. **10. Is it possible to use a dark background color to relieve the eyes?**\\ Yes, select the //space// element in the [[Configuration#colors|color configuration]] and right click on the desired background color. **11. How can I integrate a jar file with useful classes in my projects?**\\ Select //Edit// for //Classpath-User// in the [[Configuration#interpreter|interpreter configuration]] and add the jar file. **12. Deinstallation doesn't work. What can I do?**\\ If deinstallation with the setup program doesn't work just delete the Java-Editor folder. Then open the registry with //regedit// and delete the hives HKEY_LOCAL_MACHINE\Software\JavaEditor and HKEY_CURRENT_USER\Software\JavaEditor. **13. During compilation the Java-Editor switches between text and graphical screen.**\\ In this case, the fullscreen mode is enabled for the console. You can check this by opening a console by executing the //cmd// command. Press Alt+Return to switch from fullscreen mode to window mode once, then right click on the window title and select //properties//. In the options tab select the window mode to make it permanent. **14. How can I get code completion for foreign classes?**\\ You need the JavaDoc documentation for the foreign classes. Open [[Configuration#documentation|documentation]] in the configuration and use //Edit// for //JavaDoc-Folders//. Add the folder with the JavaDoc documentation. If the JavaDoc documentation is missing, you can create it if you have the source files. Open the source files in the Java-Editor and call the //JavaDoc// command from the start menu. **15. Sometimes the Java-Editor crashes without error message. What can I do?**\\ Look in your current folder. Is there a file hs_err_pid.log? Then the Java virtual machine caused the crash. Update your Java Runtime Environment to the latest version. http://www.java.com/en/download/manual.jsp **16. Why is the GUI-App on my Surface so small?**\\ Swing-Applications are not DPI-aware. A workaround is described at: https://stackoverflow.com/questions/30555401/java-disable-dpi-aware-not-working\\ Use Java FX instead of Swing. **17. Why does the debugger don't show parameters and local variables?**\\ You need the compiler parameter "-g". Set Java compiler parameter to standard ("-deprecation -g) in the configuration. **18. How can I use the serial interface?**\\ The package jSerialComm.jar is integrated via Classpath-User. A description of the API is available at https://fazecast.github.io/jSerialComm/ **19. Why doesn't the download work during the update?**\\ A change in Windows is responsible for the fact that the download no longer works up to version 19.31. Download the current version and install it over your previous version.