add合作单位导入

edu-util/src/main/java/com/keao/edu/util/excel/POIUtil.java

@@ -641,6 +641,9 @@ public class POIUtil {
      */
     public static Map<String, List<PictureData>> getXlsPictures(HSSFSheet sheet) throws IOException {
         Map<String, List<PictureData>> map = new HashMap<>();
+        if(sheet.getDrawingPatriarch() == null || sheet.getDrawingPatriarch().getChildren()==null){
+            return map;
+        }
         List<HSSFShape> list = sheet.getDrawingPatriarch().getChildren();
         for (HSSFShape shape : list) {
             if (shape instanceof HSSFPicture) {