導出信息到excel表

public String exp() throws Exception {
try {
List<Document> documents = new DocumentFacade().find(document);
if(documents != null && documents.size() > 0) {
WritableCellFormat wcformat = new WritableCellFormat();
wcformat.setAlignment(jxl.format.Alignment.CENTRE);
wcformat.setVerticalAlignment(jxl.format.VerticalAlignment.CENTRE);
wcformat.setBorder(Border.LEFT,BorderLineStyle.THIN);
wcformat.setBorder(Border.RIGHT,BorderLineStyle.THIN);
wcformat.setBorder(Border.TOP,BorderLineStyle.THIN);
wcformat.setBorder(Border.BOTTOM,BorderLineStyle.THIN);
wcformat.setWrap(true);
OutputStream os = getOutputStream();
workbook = Workbook.createWorkbook(os);
WritableSheet ws = workbook.createSheet("sheet0", 0);
int index = 0;

ws.addCell(new Label(index,1,"文檔 編號",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"公司",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"部門",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"文檔類別",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"文檔名稱",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"文檔編號",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"關聯編碼",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"關鍵字",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"文檔描述",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"鏈接",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"在線鏈接",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"備註",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"版本",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"創建人",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"創建日期",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"更新人",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"更新日期",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"查看",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"查看日期",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"狀態",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"分類Id",wcformat));
ws.setColumnView(index,20);
index++;
ws.addCell(new Label(index,1,"發行日期",wcformat));
ws.setColumnView(index,20);
index++;




int row = 2;
for(int i=0; i<documents.size();i++) {
row++;
int m = 0;
if(documents.get(i).getDocId() != null) 
ws.addCell(new jxl.write.Number(m,row,documents.get(i).getDocId(),wcformat));
m++;
if(documents.get(i).getComId() != null) 
ws.addCell(new jxl.write.Number(m,row,documents.get(i).getComId(),wcformat));
m++;
if(documents.get(i).getDeptId() != null) 
ws.addCell(new jxl.write.Number(m,row,documents.get(i).getDeptId(),wcformat));
m++;
if(documents.get(i).getCategoryCode() != null) 
ws.addCell(new jxl.write.Label(m,row,documents.get(i).getCategoryCode(),wcformat));
m++;
if(documents.get(i).getDocName() != null) 
ws.addCell(new jxl.write.Label(m,row,documents.get(i).getDocName(),wcformat));
m++;
if(documents.get(i).getDocNo() != null) 
ws.addCell(new jxl.write.Label(m,row,documents.get(i).getDocNo(),wcformat));
m++;
if(documents.get(i).getRelateCode() != null) 
ws.addCell(new jxl.write.Label(m,row,documents.get(i).getRelateCode(),wcformat));
m++;
if(documents.get(i).getDocKey() != null) 
ws.addCell(new jxl.write.Label(m,row,documents.get(i).getDocKey(),wcformat));
m++;
if(documents.get(i).getDocDesc() != null) 
ws.addCell(new jxl.write.Label(m,row,documents.get(i).getDocDesc(),wcformat));
m++;
if(documents.get(i).getUri() != null) 
ws.addCell(new jxl.write.Label(m,row,documents.get(i).getUri(),wcformat));
m++;
if(documents.get(i).getOnLineUri() != null) 
ws.addCell(new jxl.write.Label(m,row,documents.get(i).getOnLineUri(),wcformat));
m++;
if(documents.get(i).getRemark() != null) 
ws.addCell(new jxl.write.Label(m,row,documents.get(i).getRemark(),wcformat));
m++;
if(documents.get(i).getVersion() != null) 
ws.addCell(new jxl.write.Label(m,row,documents.get(i).getVersion(),wcformat));
m++;
if(documents.get(i).getCreateBy() != null) 
ws.addCell(new jxl.write.Number(m,row,documents.get(i).getCreateBy(),wcformat));
m++;
if(documents.get(i).getCreateDate() != null) 
ws.addCell(new jxl.write.DateTime(m,row,documents.get(i).getCreateDate(),wcformat));
m++;
if(documents.get(i).getLastUpd() != null) 
ws.addCell(new jxl.write.Number(m,row,documents.get(i).getLastUpd(),wcformat));
m++;
if(documents.get(i).getLastUpdDate() != null) 
ws.addCell(new jxl.write.DateTime(m,row,documents.get(i).getLastUpdDate(),wcformat));
m++;
if(documents.get(i).getReviewBy() != null) 
ws.addCell(new jxl.write.Number(m,row,documents.get(i).getReviewBy(),wcformat));
m++;
if(documents.get(i).getReviewDate() != null) 
ws.addCell(new jxl.write.DateTime(m,row,documents.get(i).getReviewDate(),wcformat));
m++;
if(documents.get(i).getStatus() != null) 
ws.addCell(new jxl.write.Number(m,row,documents.get(i).getStatus(),wcformat));
m++;
if(documents.get(i).getParentId() != null) 
ws.addCell(new jxl.write.Number(m,row,documents.get(i).getParentId(),wcformat));
m++;
if(documents.get(i).getIssueDate() != null) 
ws.addCell(new jxl.write.DateTime(m,row,documents.get(i).getIssueDate(),wcformat));
m++;


}
}
this.setMsg(MSG.S_EXP);
}
catch(Exception e) {
this.setMsg(MSG.F_EXP);
Logger.getLogger(this.getClass()).error("DocumentListAction execute Exception", e);
return ERROR;
}
return EXCEL;
}