POI導出自定義樣式EXCEL數據樣式

簡介：

POI是Apache軟件基金會用Java編寫的免費開源的跨平臺的 Java API，Apache POI提供API給Java程序對Microsoft Office格式檔案讀和寫的功能。POI為“Poor Obfuscation Implementation”的首字母縮寫，意為“簡潔版的模糊實現”。所以POI的主要功能是可以用Java操作Microsoft Office的相關文件，但是一般我們都是用來操作Excel相關文件。

需要依賴：

<code>
    org.apache.poi
    poi
    3.17


    org.apache.poi
    poi-ooxml
    3.17
/<code>

導出效果如下，實現在網頁彈出選擇保存路徑，可以合併單元格，設置字體信息，單元格行寬、列高。

<code>private void exportExcel(String parentTitle, String sheetName,
String[] headers, String[] fields, Collection dataset,
OutputStream out, String pattern, String date, int[] columnWidth) {
// 聲明一個工作薄
HSSFWorkbook workbook = new HSSFWorkbook();
// 生成一個表格
HSSFSheet sheet = workbook.createSheet(sheetName);
// 設置表格默認列寬度為15個字節
// sheet.setDefaultColumnWidth((short) 18);
// 設置表格列寬，列寬計算公式為(int)((columnWidth+0.72)*256)
for (int i = 0; i < columnWidth.length; i++) {
sheet.setColumnWidth(i, (int) ((columnWidth[i] + 0.72) * 256));
}
// 聲明一個畫圖的頂級管理器
HSSFPatriarch patriarch = sheet.createDrawingPatriarch();
// 定義註釋的大小和位置,詳見文檔
HSSFComment comment = patriarch.createComment(new HSSFClientAnchor(0,
0, 0, 0, (short) 4, 2, (short) 6, 5));
// 設置註釋內容
comment.setString(new HSSFRichTextString(parentTitle));
// 設置註釋作者，當鼠標移動到單元格上是可以在狀態欄中看到該內容.
comment.setAuthor("billz");
// 主標題
HSSFRow pTitleRow = sheet.createRow(0);
HSSFCell pTitleCell = pTitleRow.createCell(0);
pTitleCell.setCellStyle(getParentTitleStyle(workbook));
pTitleCell.setCellValue(new HSSFRichTextString(parentTitle));
// 跨第1行第1個到第2個單元格的操作為
CellRangeAddress rg = new CellRangeAddress(0, (short) 0, 0,
(short) (headers.length - 1));
sheet.addMergedRegion(rg);
pTitleRow.setHeightInPoints(35);// 目的是想把行高設置成35px
// end
// 顯示時間行，第二行
HSSFRow dateRow = sheet.createRow(1);
sheet.addMergedRegion(new CellRangeAddress(1, 1, headers.length - 2,
headers.length - 1));
dateRow.setHeight((short) 400);
HSSFCell dateCell = dateRow.createCell(headers.length - 2);
dateCell.setCellStyle(getDateStyle(workbook));
dateCell.setCellValue(new HSSFRichTextString(date));
// 產生表格標題行
HSSFRow row = sheet.createRow(2);
row.setHeight((short) 0x279);
for (int i = 0; i < headers.length; i++) {
HSSFCell cell = row.createCell(i);
cell.setCellStyle(getTitleStyle(workbook));
HSSFRichTextString text = new HSSFRichTextString(headers[i]);
cell.setCellValue(text);
}
// 遍歷集合數據，產生數據行
Iterator it = dataset.iterator();
int index = 2;
while (it.hasNext()) {
index++;
row = sheet.createRow(index);
row.setHeight((short) 512);
T t = it.next();
// 利用反射，根據javabean屬性的先後順序，動態調用getXxx()方法得到屬性值
for (int i = 0; i < fields.length; i++) {
HSSFCell cell = row.createCell(i);
cell.setCellStyle(getValueStyle(workbook));
String fieldName = fields[i];
String getMethodName = "get"
+ fieldName.substring(0, 1).toUpperCase()
+ fieldName.substring(1);
try {
Method getMethod = t.getClass().getMethod(getMethodName,
new Class[] {});
Object value = getMethod.invoke(t, new Object[] {});
// 判斷值的類型後進行強制類型轉換
String textValue = null;
if (value instanceof Boolean) {
boolean bValue = (Boolean) value;
textValue = "是";
if (!bValue) {
textValue = "否";
}
} else if (value instanceof Date) {
Date date1 = (Date) value;
SimpleDateFormat sdf = new SimpleDateFormat(pattern);
textValue = sdf.format(date1);
} else if (value instanceof byte[]) {
// 有圖片時，設置行高為60px;
row.setHeightInPoints(60);
// 設置圖片所在列寬度為80px,注意這裡單位的一個換算
sheet.setColumnWidth(i, (short) (35.7 * 80));
// sheet.autoSizeColumn(i);
byte[] bsValue = (byte[]) value;
HSSFClientAnchor anchor = new HSSFClientAnchor(0, 0,
1023, 255, (short) 6, index, (short) 6, index);
anchor.setAnchorType(2);
patriarch.createPicture(anchor, workbook.addPicture(
bsValue, HSSFWorkbook.PICTURE_TYPE_JPEG));
} else if (value instanceof Long) { // long類型的時間字符串轉為固定格式（yy/MM/dd
// hh:mm）String字符串
String dateStr = String.valueOf(value);
String year = dateStr.substring(0, 4) + "/";
String month = dateStr.substring(4, 6) + "/";
String day = dateStr.substring(6, 8) + " ";
String hour = dateStr.substring(8, 10) + ":";
String minute = dateStr.substring(10, 12);
textValue = year + month + day + hour + minute;
} else {
// 其它數據類型都當作字符串簡單處理
textValue = value != null ? value.toString() : "";
}
// 如果不是圖片數據，就利用正則表達式判斷textValue是否全部由數字組成
if (textValue != null) {
Pattern p = Pattern.compile("^//d+(//.//d+)?$");
Matcher matcher = p.matcher(textValue);
if (matcher.matches()) {
// 是數字當作double處理
cell.setCellValue(Double.parseDouble(textValue));
} else {
HSSFRichTextString richString = new HSSFRichTextString(
textValue);
HSSFFont font3 = workbook.createFont();
// font3.setColor(HSSFColor.BLUE.index);
richString.applyFont(font3);
cell.setCellValue(richString);
}
}
} catch (Exception e) {
e.printStackTrace();
} finally {
// 清理資源
}
}
}
try {
workbook.write(out);
} catch (IOException e) {
e.printStackTrace();
}
}/<code>