1，先把要导出的模板转成xml格式，然后加到项目中，将后缀名改成.vm

2.以下是工具类，两种（一个是导出指定位置，一个是浏览器下载）

工具类代码如下：

public class VelocityUtil {  /**
* 将内容写到vm模板中,存放在指定目录下
* VelocityContext 传送内容类
* list 数据集合
* colMap 列名字
* templetePath 模板
* */public static void createDoc(List list, String templetePath,String docpath,Map<String,String> colMap) throws Exception { VelocityContext vc = new VelocityContext();  //传到vm的内容String classpath = VelocityUtil.class.getResource("/").getPath(); Properties ps = new Properties();  ps.setProperty(VelocityEngine.FILE_RESOURCE_LOADER_PATH, classpath.substring(0, classpath.length()-8) + "template/import");// 这是模板所在路径  VelocityEngine ve = new VelocityEngine();  ve.init(ps);  Template template = ve.getTemplate(templetePath+".vm", "utf-8");  File srcFile = new File(docpath);//输出路径  FileOutputStream fos = new FileOutputStream(srcFile);  BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(fos, "utf-8"));  Set<String> cols = colMap.keySet();List<String> colspan = new ArrayList<>();for (String col : cols) {colspan.add(colMap.get(col).replace("\"", ""));
}vc.put("list", list);//数据集合vc.put("cols", colspan);//列集合template.merge(vc, writer);  writer.flush();  writer.close();  fos.close();  }  /*** 由浏览器下载导出的表格* @param list* @param templeteName 模板名称* @param excelName 导出表格名称* @param response* @param colMap 列*/
public static void createDoc(List list, String templeteName, String excelName,
HttpServletResponse response, Map<String, String> colMap) {
try {
VelocityContext vc = new VelocityContext();  //传到vm的内容String classpath = VelocityUtil.class.getResource("/").getPath(); Properties ps = new Properties();  ps.setProperty(VelocityEngine.FILE_RESOURCE_LOADER_PATH, classpath.substring(0, classpath.length()-8) + "template/import");// 这是模板所在路径  VelocityEngine ve = new VelocityEngine();  ve.init(ps);  Template template = ve.getTemplate(templeteName+".vm", "utf-8");List<String> helpList = new ArrayList<String>(colMap.keySet());
Collections.sort(helpList, new Comparator<String>() {
public int compare(String a, String b) {
return a.compareTo(b);
}
});
Set<String> cols = new TreeSet<String>(helpList);List<String> colsEN = new ArrayList<>();List<String> colsCN = new ArrayList<>();for (String col : cols) {colsCN.add(colMap.get(col).replace("\"", ""));colsEN.add(col.split("_")[1]);
}vc.put("list", list);//数据集合vc.put("colsCN", colsCN);//列集合vc.put("colsEN", colsEN);//列集合response.addHeader("Cache-Control","no-cache");  response.setCharacterEncoding("UTF-8");  response.setContentType("application/vnd.ms-excel;charset=UTF-8");  response.addHeader("Content-Disposition","attachment;filename=" + new String(excelName.getBytes(),"ISO8859-1"));  PrintWriter write = response.getWriter();//解析模版  template.merge(vc, write);if(write != null){  write.flush();  write.close();  }  
} catch (Exception e) {
e.printStackTrace();
}
}
}