当我尝试使用 src/Default.docx 中的 docx 文件时，它不会让我将它用于 XWPFDocument。docx 文件甚至是我构建路径的一部分。我正在使用 POI API，并且正确安装了所有外部 jar。（如果我使用桌面路径而不是类路径，则此方法有效）
InputStream file = getClass().getClassLoader().getResourceAsStream("Default.docx");
XWPFDocument document = new XWPFDocument(file);
给我：
java.lang.NullPointerException: in is null
at java.util.zip.ZipInputStream.<init>(ZipInputStream.java:64)
at org.apache.poi.openxml4j.opc.ZipPackage.<init>(ZipPackage.java:83)
at org.apache.poi.openxml4j.opc.OPCPackage.open(OPCPackage.java:267)
at org.apache.poi.util.PackageHelper.open(PackageHelper.java:39)
at org.apache.poi.xwpf.usermodel.XWPFDocument.<init>(XWPFDocument.java:120)
at thompsons.printer.Format.<init>(Format.java:15)
at thompsons.printer.Printer.print(Printer.java:15)
at thompsons.ui.MainPanel$3.actionPerformed(MainPanel.java:238)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2028)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2351)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
at java.awt.Component.processMouseEvent(Component.java:6382)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3275)
at java.awt.Component.processEvent(Component.java:6147)
at java.awt.Container.processEvent(Container.java:2083)
at java.awt.Component.dispatchEventImpl(Component.java:4744)
at java.awt.Container.dispatchEventImpl(Container.java:2141)
at java.awt.Component.dispatchEvent(Component.java:4572)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4619)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4280)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4210)
at java.awt.Container.dispatchEventImpl(Container.java:2127)
at java.awt.Window.dispatchEventImpl(Window.java:2489)
at java.awt.Component.dispatchEvent(Component.java:4572)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:710)
at java.awt.EventQueue.access$400(EventQueue.java:82)
at java.awt.EventQueue$2.run(EventQueue.java:669)
at java.awt.EventQueue$2.run(EventQueue.java:667)
at java.security.AccessController.doPrivileged(Native Method)