java簡單的從數據庫查詢數據使用POI導出excel文件

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使用java簡單的從數據庫中查詢數據，而後寫入到excel中，數據的類型爲 List<Map<String, Object>>格式的數據。

首先下載POI的jar包，網址：https://poi.apache.org/download.html#POI-3.16-beta2

而後導入jar包到工程下

：

此外還須要 commons-collections4-4.1.jar 和 xmlbeans-2.6.0.jar 兩個額外的jar包，由於我使用的是 3.15 版本的，因此 commons-collections4-4.1.jar  須要使用 4.1 版本的，原來使用的是 4.0 ，報錯了。

這兩個包能夠在這裏下載：

https://mvnrepository.com/artifact/org.apache.xmlbeans/xmlbeans/2.6.0

https://mvnrepository.com/artifact/org.apache.commons/commons-collections4/4.1

導入的類：

import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.ss.usermodel.BorderStyle;
import org.apache.poi.ss.usermodel.FillPatternType;
import org.apache.poi.ss.usermodel.HorizontalAlignment;
import org.apache.poi.ss.usermodel.VerticalAlignment;
import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFCellStyle;
import org.apache.poi.xssf.usermodel.XSSFClientAnchor;
import org.apache.poi.xssf.usermodel.XSSFComment;
import org.apache.poi.xssf.usermodel.XSSFDrawing;
import org.apache.poi.xssf.usermodel.XSSFFont;
import org.apache.poi.xssf.usermodel.XSSFRichTextString;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

 

由於須要解析成爲 .xlsx 格式的 Excel 文件，因此須要的是 XSSFWorkbook.

準備數據：

public static List<Map<String, Object>> getData() {
		List<Map<String, Object>> data = new ArrayList<>();
		// 使用 LinkedHashMap 保證有序，即標題和數據對應上
		Map<String, Object> map1 = new LinkedHashMap<>();
		map1.put("id", 1);
		map1.put("name", "張三");
		map1.put("age", 23);
		map1.put("sex", "男");
		
		Map<String, Object> map2 = new LinkedHashMap<>();
		map2.put("id", 2);
		map2.put("name", "李四");
		map2.put("age", 20);
		map2.put("sex", "女");
		
		Map<String, Object> map3 = new LinkedHashMap<>();
		map3.put("id", 3);
		map3.put("name", "王五");
		map3.put("age", 19);
		map3.put("sex", "男");
		
		Map<String, Object> map4 = new LinkedHashMap<>();
		map4.put("id", 4);
		map4.put("name", "趙六");
		map4.put("age", 18);
		map4.put("sex", "女");
		
		Map<String, Object> map5 = new LinkedHashMap<>();
		map5.put("id", 5);
		map5.put("name", "小七");
		map5.put("age", 22);
		map5.put("sex", "男");
		
		data.add(map1);
		data.add(map2);
		data.add(map3);
		data.add(map4);
		data.add(map5);
	
		return data;
	}

PS : 懶得去鏈接數據庫查詢了，就本身隨便搞了一個。

下面就是把數據寫到 Excel 文件中，只能建立一個 sheet。

/** 
     *  導出Excel
     * @param sheetName 表格 sheet 的名稱
     * @param headers  標題名稱
     * @param dataList 須要顯示的數據集合
     * @param exportExcelName 導出excel文件的名字
     */ 
	public  static void exportExcel(String sheetName, List<Map<String, Object>> dataList,
				String[] headers,String exportExcelName) {

		// 聲明一個工做薄
		XSSFWorkbook  workbook = new XSSFWorkbook();
		// 生成一個表格
		XSSFSheet sheet = workbook.createSheet(sheetName);
		// 設置表格默認列寬度爲15個字節
		sheet.setDefaultColumnWidth(15);
		
		// 生成表格中非標題欄的樣式
		XSSFCellStyle style = workbook.createCellStyle();
		// 設置這些樣式
		style.setFillForegroundColor(HSSFColor.WHITE.index);//背景色
		style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
		style.setBorderBottom(BorderStyle.THIN);
		style.setBorderLeft(BorderStyle.THIN);
		style.setBorderRight(BorderStyle.THIN);
		style.setBorderTop(BorderStyle.THIN);
		style.setAlignment(HorizontalAlignment.CENTER);
		// 生成表格中非標題欄的字體
		XSSFFont font = workbook.createFont();
		font.setColor(HSSFColor.BLACK.index);
		font.setFontHeightInPoints((short) 12);
		font.setBold(true);
		// 把字體應用到當前的樣式
		style.setFont(font);
		

		// 設置表格標題欄的樣式
		XSSFCellStyle titleStyle = workbook.createCellStyle();
		titleStyle.setFillForegroundColor(HSSFColor.BLUE_GREY.index);
		titleStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND);
		titleStyle.setBorderBottom(BorderStyle.THIN);
		titleStyle.setBorderLeft(BorderStyle.THIN);
		titleStyle.setBorderRight(BorderStyle.THIN);
		titleStyle.setBorderTop(BorderStyle.THIN);
		titleStyle.setAlignment(HorizontalAlignment.CENTER);
		titleStyle.setVerticalAlignment(VerticalAlignment.CENTER);
		// 設置標題欄字體
		XSSFFont titleFont = workbook.createFont();
		titleFont.setColor(HSSFColor.WHITE.index);
		titleFont.setFontHeightInPoints((short) 12);
		titleFont.setBold(true);
		// 把字體應用到當前的樣式
		titleStyle.setFont(titleFont);
		
		// 產生表格標題行
		XSSFRow row = sheet.createRow(0);
		for (short i = 0; i < headers.length; i++) {
			XSSFCell cell = row.createCell(i);
			cell.setCellStyle(titleStyle);
			XSSFRichTextString text = new XSSFRichTextString(headers[i]);
			cell.setCellValue(text);
		}
		
        // 遍歷集合數據，產生數據行
		Iterator<Map<String, Object>> it = dataList.iterator();
		int index = 0;
		while (it.hasNext()) {
			index++;
			row = sheet.createRow(index);
			Map<String, Object> data = it.next();
			int i = 0;
			for(String key : data.keySet()){
				XSSFCell cell = row.createCell(i);
				cell.setCellStyle(style);
				XSSFRichTextString text = new XSSFRichTextString(data.get(key)+"");
				cell.setCellValue(text);
				i++;
			}
		}
		try {
            
            OutputStream out = null;	
			String tmpPath = "G:\\excel\\" + exportExcelName + ".xlsx";
			out = new FileOutputStream(tmpPath);
			workbook.write(out);
		} catch (IOException e) {
			e.printStackTrace();
		}finally{
			if(workbook != null){
				try {
					workbook.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if(out != null){
				try {
					out.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}

 

測試：

public static void main(String[] args) {
		List<Map<String, Object>> data = MyExecl.getData();
		String sheetName = "學生表";
		String[] headers = {"ID","名稱","年齡","性別"};
		String exportExcelName = "student";
		MyExecl.exportExcel(sheetName, data, headers, exportExcelName);
	}

 

結果：

 

重構上面的代碼，封裝一下

/**
    * 建立每一個 sheet 頁的數據
    */
    private void createSheetData(HSSFWorkbook aWorkbook, String[] aTitles, String aSheetName,
                                 List<String[]> aRowData) {
        HSSFSheet tmpSheet = aWorkbook.createSheet(aSheetName);
        // 設置sheet的標題
        HSSFRow tmpTitileRow = tmpSheet.createRow(0);
        for (int i = 0; i < aTitles.length; i++) {
            tmpTitileRow.createCell(i).setCellValue(aTitles[i]);
        }
        // 遍歷填充每行的數據
        HSSFRow tmpRow = null;
        int tmpRowNumber = 1;
        for (String[] rowData : aRowData) {
            tmpRow = tmpSheet.createRow(tmpRowNumber);
            for (int i = 0; i < rowData.length; i++) {
                tmpRow.createCell(i).setCellValue(rowData[i]);
            }
            tmpRowNumber++;
        }
    }

    /**
     * 設置響應頭
     */
    private void setResponseHeader(HttpServletResponse aResponse, String aFileName){
       try {
           try {
               aFileName = new String(aFileName.getBytes(), "ISO8859-1");
           } catch (UnsupportedEncodingException e) {
               e.printStackTrace();
           }
           aResponse.setContentType("application/octet-stream;charset=ISO8859-1");
           aResponse.setHeader("Content-Disposition", "attachment;filename=" + aFileName);
           aResponse.addHeader("Pargam", "no-cache");
           aResponse.addHeader("Cache-Control", "no-cache");
       } catch (Exception e) {
        e.printStackTrace();
        }
    }

測試：

/**
     * 經過頁面導出
     * @param aResponse
     * @throws IOException
     */
    public void export(HttpServletResponse aResponse) throws IOException {
        HSSFWorkbook tmpWorkbook = new HSSFWorkbook();
        String[] tmpUserTitles = {"姓名", "性別", "年齡", "工做"};
        List<String[]> tmpUsers = getUsers();
        createSheetData(tmpWorkbook, tmpUserTitles, "用戶信息", tmpUsers);
        setResponseHeader(aResponse, "用戶信息表.xls");
        OutputStream tmpOutputStream = aResponse.getOutputStream();
        tmpWorkbook.write(tmpOutputStream);
        tmpOutputStream.flush();
        tmpOutputStream.close();
    }

    /**
     * 導出，不經過頁面導出
     */
    public void export() throws IOException {
        HSSFWorkbook tmpWorkbook = new HSSFWorkbook();
        String[] tmpUserTitles = {"姓名", "性別", "年齡", "工做"};
        List<String[]> tmpUsers = getUsers();
        createSheetData(tmpWorkbook, tmpUserTitles, "用戶信息", tmpUsers);
        String[] tmpAddressTitles = {"城市", "區域"};
        List<String[]> getAddress = getAddress();
        createSheetData(tmpWorkbook, tmpAddressTitles, "地址信息", getAddress);
        OutputStream tmpOutputStream = new FileOutputStream("E:\\" + System.currentTimeMillis() + ".xls");
        tmpWorkbook.write(tmpOutputStream);
        tmpOutputStream.flush();
        tmpOutputStream.close();
    }

	/**
	* 測試數據
	*/
    private List<String[]> getAddress(){
        List<String[]> address = new ArrayList<>();
        for(int i = 1; i <= 5; i++){
            String[] addr = new String[2];
            addr[0] = "四川";
            addr[1] = "高新 - " + i;
            address.add(addr);
        }
        return address;
    }
	/**
	* 測試數據
	*/
    private List<String[]> getUsers(){
        List<String[]> users = new ArrayList<>();
        for(int i = 0; i < 10; i++){
            String[] user = new String[4];
            user[0] = "zhangsan - " + i;
            user[1] = "男";
            user[2] = "2" + i;
            user[3] = "Java - " + i;
            users.add(user);
        }
        return users;
    }

給單元格添加批註

@SuppressWarnings("resource")
	private void download(HttpServletResponse resp) throws IOException 
	{
		XSSFWorkbook  workbook = new XSSFWorkbook();
		XSSFSheet sheet = workbook.createSheet("用戶表");
		XSSFRow row = sheet.createRow(0);
		
        XSSFDrawing p=sheet.createDrawingPatriarch();
       
        XSSFCell cel0 = row.createCell(13);
        XSSFComment comment=p.createCellComment(new XSSFClientAnchor(0,0,0,0,(short)0,0,(short)2,4));
        comment.setString(new XSSFRichTextString("選填項\r\n最多512個字符"));
		cel0.setCellValue("名稱");
		cel0.setCellComment(comment);
		
		XSSFCell cel1 = row.createCell(14);
		XSSFComment comment1=p.createCellComment(new XSSFClientAnchor(0,0,0,0,(short)1,0,(short)3,4));
		comment1.setString(new XSSFRichTextString("選填項\r\n最多512個字符"));
		cel1.setCellValue("年齡");
		cel1.setCellComment(comment1);
		
		// 批註相關
		XSSFCell tmpCell = null;
		XSSFComment tmpComment = null;
		XSSFRichTextString tmpVal = new XSSFRichTextString("選填項\r\n最多512個字符");
		int dx1 = 80;
		int dx2 = 140;
		short col1 = 15; // 批註開始的列，即15列
		short col2 = 17; // 批註結束的列，即17列
		// 動態建立列和列上的批註
		for(int i = 1; i <= 5; i++)
		{
			tmpCell = row.createCell(row.getLastCellNum());
			tmpComment = p.createCellComment(new XSSFClientAnchor(dx1,0,dx2,0, col1,0, col2,4));
			tmpCell.setCellValue("擴展裂-" + i);
			tmpComment.setString(tmpVal);
			col1++;
			col2++;
		}
		
		setResponseHeader(resp, "用戶表.xlsx");
	    OutputStream tmpOutputStream = resp.getOutputStream();
	    workbook.write(tmpOutputStream);
        tmpOutputStream.flush();
        tmpOutputStream.close();
	}

 

注意： 建立批註的類 XSSFClientAnchor 的構造參數有四個 ：

public XSSFClientAnchor(int dx1, int dy1, int dx2, int dy2, int col1, int row1, int col2, int row2){....}

它們的做用以下：

    dx1，dy1 ：起始單元格中的 x, y 座標.

    dx2，dy2 ：結束單元格中的 x , y 座標

    col1，row1 ：指定起始的單元格，下標從0開始

    col2,，row2 ：指定結束的單元格 ，下標從0開始