如何配置Google AppEngine以使用矢量图形？
在使用Java8的AppEngine标准环境中尝试使用SVG时出现下一个错误。 当我尝试使用POI（如slide.draw(graphics2D)在XSLFSlide上绘制SVG或使用Batik将SVG转换为PNG时，我收到此错误。 似乎出现问题是因为fontconfig无法找到字体。 在debian发行版中，它通过安装libfontconfig1来解决。 如何在AppEngine上解决它？
java.lang.NullPointerException at sun.awt.FontConfiguration.getVersion(FontConfiguration.java:1264) at sun.awt.FontConfiguration.readFontConfigFile(FontConfiguration.java:219) at sun.awt.FontConfiguration.init(FontConfiguration.java:107) at sun.awt.X11FontManager.createFontConfiguration(X11FontManager.java:774) at sun.font.SunFontManager$2.run(SunFontManager.java:431) at java.security.AccessController.doPrivileged(Native Method) at sun.font.SunFontManager.(SunFontManager.java:376) at sun.awt.FcFontManager.(FcFontManager.java:35) at sun.awt.X11FontManager.(X11FontManager.java:57) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:423) at java.lang.Class.newInstance(Class.java:443) at sun.font.FontManagerFactory$1.run(FontManagerFactory.java:83) at java.security.AccessController.doPrivileged(Native Method) at sun.font.FontManagerFactory.getInstance(FontManagerFactory.java:74) at java.awt.Font.getFont2D(Font.java:491) at java.awt.Font.canDisplay(Font.java:1980) at org.apache.poi.sl.draw.DrawTextParagraph.canDisplayUpTo(DrawTextParagraph.java:756) at org.apache.poi.sl.draw.DrawTextParagraph.getAttributedString(DrawTextParagraph.java:640) at org.apache.poi.sl.draw.DrawTextParagraph.breakText(DrawTextParagraph.java:248) at org.apache.poi.sl.draw.DrawTextShape.drawParagraphs(DrawTextShape.java:159) at org.apache.poi.sl.draw.DrawTextShape.getTextHeight(DrawTextShape.java:220) at org.apache.poi.sl.draw.DrawTextShape.drawContent(DrawTextShape.java:102) at org.apache.poi.sl.draw.DrawSimpleShape.draw(DrawSimpleShape.java:93) at org.apache.poi.sl.draw.DrawSheet.draw(DrawSheet.java:71) at org.apache.poi.sl.draw.DrawSlide.draw(DrawSlide.java:41) at org.apache.poi.xslf.usermodel.XSLFSlide.draw(XSLFSlide.java:307)
我遇到了同样的问题，并设法通过设置"sun.awt.fontconfig"系统属性，明确地告诉AppEngine VM一个特定的字体配置来解决它。 尝试在源代码的最开头的某处插入以下代码（在使用任何字体或图形组件之前）：
String fontConfig = System.getProperty("java.home") + File.separator + "lib" + File.separator + "fontconfig.Prodimage.properties"; if (new File(fontConfig).exists()) System.setProperty("sun.awt.fontconfig", fontConfig);