问题描述
添加AWT的动机：在前端添加一个对话框，允许用户将文件保存在所需的位置。
当我在本地运行（在 Eclipse 中使用 Tomcat7.0）时代码工作正常，而在使用 Tomact 7.0 JDK 1.7 的虚拟服务器上运行时失败并抛出 awt headless 异常。
No X11 disPLAY variable was set,but this program performed an operation which is required
尝试了以下修复，但仍然无效
System.setProperty(“java.awt.headless”,“false”);
System.out.println(java.awt.GraphicsEnvironment.isHeadless());
请帮助如何在 Java 中解决此问题.. 在 Unix 服务器中 X11forwarding 已启用
选项 1：尝试将无头值设为 true 并获得相同的无头异常
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.java.Sample#0' defined in ServletContext resource [/WEB-INF/manage-servlet.xml]: Bean instantiation via constructor Failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.java.Sample]: Constructor threw exception; nested exception is java.awt.HeadlessException:
选项 2：将无头值添加为 false 并低于异常
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.java.Sample#0' defined in ServletContext resource [/WEB-INF/manage-servlet.xml]: Bean instantiation via constructor Failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.java.Sample]: Constructor threw exception; nested exception is java.lang.InternalError: Can't connect to X11 window server using ':0.0' as the value of the disPLAY variable. at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:279)
选项 3：将显示变量添加为 false 并在启动脚本中添加命令 false 然后它也因以下异常而失败
java.lang.NoClassDefFoundError: Could not initialize class sun.awt.X11GraphicsEnvironment java.lang.class.forName0(Native Method) java.lang.class.forName(Class.java:195) java.awt.GraphicsEnvironment.createGE(GraphicsEnvironment.java:102) java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEnvironment.java:81) java.awt.Window.initGC(Window.java:467)
System.setProperty("java.awt.headless","false");
JFileChooser fileChooser = new JFileChooser(); fileChooser.setDialogTitle("Users"); int userSelection = fileChooser.showSaveDialog(this); if (userSelection == JFileChooser.APPROVE_OPTION) { File filetoSave = fileChooser.getSelectedFile(); FileOutputStream fileout = new FileOutputStream(filetoSave.getAbsolutePath()); AUDIT.info("Save as file: " + filetoSave.getAbsolutePath());
我厌倦了这种无头异常处理，却没有办法解决这个问题。
解决方法
我在加载 Java UI 时也遇到了同样的错误。下面的命令修复了我的 CentOS 7.x 版本的问题。
导出显示=:0