NPE in sun.awt.FontConfiguration.getVersion

异常详情

Java在Ubuntu下访问字体方法报NPE。具体堆栈信息如下：

Caused by: java.lang.NullPointerException
         at sun.awt.FontConfiguration.getVersion(FontConfiguration.java:1262) ~[?:?]
         at sun.awt.FontConfiguration.readFontConfigFile(FontConfiguration.java:225) ~[?:?]
         at sun.awt.FontConfiguration.init(FontConfiguration.java:107) ~[?:?]
         at sun.awt.X11FontManager.createFontConfiguration(X11FontManager.java:719) ~[?:?]
         at sun.font.SunFontManager$2.run(SunFontManager.java:367) ~[?:?]
         at java.security.AccessController.doPrivileged(AccessController.java:310) ~[?:?]
         at sun.font.SunFontManager.(SunFontManager.java:312) ~[?:?]
         at sun.awt.FcFontManager.(FcFontManager.java:35) ~[?:?]
         at sun.awt.X11FontManager.(X11FontManager.java:56) ~[?:?]
         at jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:?]
         at jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[?:?]
         at jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[?:?]
         at java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500) ~[?:?]
         at java.lang.reflect.Constructor.newInstance(Constructor.java:481) ~[?:?]
         at sun.font.FontManagerFactory$1.run(FontManagerFactory.java:84) ~[?:?]
         at java.security.AccessController.doPrivileged(AccessController.java:310) ~[?:?]
         at sun.font.FontManagerFactory.getInstance(FontManagerFactory.java:74) ~[?:?]
         at sun.font.SunFontManager.getInstance(SunFontManager.java:247) ~[?:?]
         at sun.font.FontDesignMetrics.getMetrics(FontDesignMetrics.java:265) ~[?:?]
         at sun.java2d.SunGraphics2D.getFontMetrics(SunGraphics2D.java:856) ~[?:?]

解决方案

ubuntu

sudo apt install fontconfig

centos

sudo yum install fontconfig

 Reading package lists… Done
 Building dependency tree       
 Reading state information… Done
 The following additional packages will be installed:
   fontconfig-config fonts-dejavu-core libfontconfig1
 The following NEW packages will be installed:
   fontconfig fontconfig-config fonts-dejavu-core libfontconfig1
 0 upgraded, 4 newly installed, 0 to remove and 0 not upgraded.
 Need to get 1,355 kB of archives.
 After this operation, 3,902 kB of additional disk space will be used.

具体原因

jdk缺少字体, 在生成图片时获取不到font导致NPE。