導出功能實現

工具類：

import java.io.*;
import java.lang.reflect.*;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.text.SimpleDateFormat;
import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.ss.util.CellRangeAddress;


public class ExportExcel {

    /**
     * 功能: 導出爲Excel工做簿
     * 參數: sheetName[工做簿中的一張工做表的名稱]
     * 參數: titleName[表格的標題名稱]
     * 參數: headers[表格每一列的列名]
     * 參數: dataSet[要導出的數據源]
     * 參數: resultUrl[導出的excel文件地址]
     * 參數: pattern[時間類型數據的格式]
     */
    public static void exportExcel(String sheetName,String titleName,String[] headers,Collection<?> dataSet,String resultUrl,String pattern) {

        doExportExcel(sheetName,titleName,headers,dataSet,resultUrl,pattern);

    }

    /**
     * 功能:真正實現導出
     */
    private static void doExportExcel(String sheetName,String titleName,String[] headers,Collection<?> dataSet,String resultUrl,String pattern) {

        // 聲明一個工做薄
        HSSFWorkbook workbook = new HSSFWorkbook();

        // 生成一個工做表
        HSSFSheet sheet = workbook.createSheet(sheetName);
        // 設置工做表默認列寬度爲20個字節
        sheet.setDefaultColumnWidth((short) 20);
        //在工做表中合併首行並居中
        sheet.addMergedRegion(new CellRangeAddress(0,0,0,headers.length-1));

        // 建立[標題]樣式
        HSSFCellStyle titleStyle = workbook.createCellStyle();
        // 設置[標題]樣式
        titleStyle.setFillForegroundColor(HSSFColor.LIGHT_BLUE.index);
        titleStyle.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
        titleStyle.setBorderBottom(HSSFCellStyle.BORDER_THIN);
        titleStyle.setBorderLeft(HSSFCellStyle.BORDER_THIN);
        titleStyle.setBorderRight(HSSFCellStyle.BORDER_THIN);
        titleStyle.setBorderTop(HSSFCellStyle.BORDER_THIN);
        titleStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        //建立[標題]字體
        HSSFFont titleFont = workbook.createFont();
        //設置[標題]字體
        titleFont.setColor(HSSFColor.WHITE.index);
        titleFont.setFontHeightInPoints((short) 24);
        titleFont.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
        // 把[標題字體]應用到[標題樣式]
        titleStyle.setFont(titleFont);

        // 建立[列首]樣式
        HSSFCellStyle headersStyle = workbook.createCellStyle();
        // 設置[列首]樣式
        headersStyle.setFillForegroundColor(HSSFColor.LIGHT_ORANGE.index);
        headersStyle.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
        headersStyle.setBorderBottom(HSSFCellStyle.BORDER_THIN);
        headersStyle.setBorderLeft(HSSFCellStyle.BORDER_THIN);
        headersStyle.setBorderRight(HSSFCellStyle.BORDER_THIN);
        headersStyle.setBorderTop(HSSFCellStyle.BORDER_THIN);
        headersStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        //建立[列首]字體
        HSSFFont headersFont = workbook.createFont();
        //設置[列首]字體
        headersFont.setColor(HSSFColor.VIOLET.index);
        headersFont.setFontHeightInPoints((short) 12);
        headersFont.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
        // 把[列首字體]應用到[列首樣式]
        headersStyle.setFont(headersFont);

        // 建立[表中數據]樣式
        HSSFCellStyle dataSetStyle = workbook.createCellStyle();
        // 設置[表中數據]樣式
        dataSetStyle.setFillForegroundColor(HSSFColor.GOLD.index);
        dataSetStyle.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
        dataSetStyle.setBorderBottom(HSSFCellStyle.BORDER_THIN);
        dataSetStyle.setBorderLeft(HSSFCellStyle.BORDER_THIN);
        dataSetStyle.setBorderRight(HSSFCellStyle.BORDER_THIN);
        dataSetStyle.setBorderTop(HSSFCellStyle.BORDER_THIN);
        dataSetStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        dataSetStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
        // 建立[表中數據]字體
        HSSFFont dataSetFont = workbook.createFont();
        // 設置[表中數據]字體
        dataSetFont.setBoldweight(HSSFFont.BOLDWEIGHT_NORMAL);
        dataSetFont.setColor(HSSFColor.BLUE.index);
        // 把[表中數據字體]應用到[表中數據樣式]
        dataSetStyle.setFont(dataSetFont);

        //建立標題行-增長樣式-賦值
        HSSFRow titleRow = sheet.createRow(0);
        HSSFCell titleCell = titleRow.createCell(0);
        titleCell.setCellStyle(titleStyle);
        titleCell.setCellValue(titleName);

        // 建立列首-增長樣式-賦值
        HSSFRow row = sheet.createRow(1);
        for (short i = 0; i < headers.length; i++) {

            @SuppressWarnings("deprecation")
            HSSFCell cell = row.createCell(i);
            cell.setCellStyle(headersStyle);
            HSSFRichTextString text = new HSSFRichTextString(headers[i]);
            cell.setCellValue(text);

        }

        // 建立表中數據行-增長樣式-賦值
        Iterator<?> it = dataSet.iterator();
        int index = 1;
        while (it.hasNext()) {
            index++;
            row = sheet.createRow(index);   
            Object t = it.next();
            // 利用反射，根據javabean屬性的前後順序，動態調用getXxx()方法獲得屬性值
            Field[] fields = t.getClass().getDeclaredFields();
            for (short i = 0; i < fields.length; i++) {
                @SuppressWarnings("deprecation")
                HSSFCell cell = row.createCell(i);
                cell.setCellStyle(dataSetStyle);
                Field field = fields[i];
                String fieldName = field.getName();
                String getMethodName = "get"+ fieldName.substring(0, 1).toUpperCase()+ fieldName.substring(1);
                try {
                    @SuppressWarnings("rawtypes")
                    Class tCls = t.getClass();
                    @SuppressWarnings("unchecked")
                    Method getMethod = tCls.getMethod(getMethodName,new Class[] {});
                    Object value = getMethod.invoke(t, new Object[] {});

                    // 若是是時間類型,按照格式轉換
                    String textValue = null;
                    if (value instanceof Date) {
                        Date date = (Date) value;
                        SimpleDateFormat sdf = new SimpleDateFormat(pattern);
                        textValue = sdf.format(date);
                    } else {
                        // 其它數據類型都看成字符串簡單處理
                        textValue = value.toString();
                    }

                    // 利用正則表達式判斷textValue是否所有由數字組成
                    if (textValue != null) {
                        Pattern p = Pattern.compile("^\\d+(\\.\\d+)?$");
                        Matcher matcher = p.matcher(textValue);
                        if (matcher.matches()) {
                            // 是數字看成double處理
                            cell.setCellValue(Double.parseDouble(textValue));
                        } else {
                            // 不是數字作普通處理
                            cell.setCellValue(textValue);
                        }
                    }

                    OutputStream out=null;
                    try {
                        out = new FileOutputStream(resultUrl);
                        workbook.write(out);
                    } catch (IOException e) {
                        e.printStackTrace();
                    }finally{
                        try {
                            out.close();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }

                } catch (SecurityException e) {
                    e.printStackTrace();
                } catch (NoSuchMethodException e) {
                    e.printStackTrace();
                } catch (IllegalArgumentException e) {
                    e.printStackTrace();
                } catch (IllegalAccessException e) {
                    e.printStackTrace();
                } catch (InvocationTargetException e) {
                    e.printStackTrace();
                } finally {
                    //清理資源
                    try {
                        workbook.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
        }
    }
}

測試類：

@Test
public void tet(){
   String sheetName="repayment";
   String titleName="repayment";
   String[] headers = { "SqlNo", "ALoan_no", "term_no", "Application_no","PeriodSupply","Principal","Interest","Surplus_principal","EffectiveState","isRepaid","repayment_date" };
   //List<Book> dataSet = service.selectBookList();
   List<Repayment> queryall = repaymentMapper.queryall();
   String resultUrl="E:\\test1.xls";
   String pattern="yyyy-MM-dd";
   ExportExcel.exportExcel(sheetName, titleName, headers, queryall, resultUrl, pattern);
}

controller層代碼

@ResponseBody
@RequestMapping("/export")
public String save() throws Exception
{
    String sheetName="repayment";
    String titleName="repayment";
    String[] headers = { "SqlNo", "ALoan_no", "term_no", "Application_no","PeriodSupply","Principal","Interest","Surplus_principal","EffectiveState","isRepaid","repayment_date" };
    //List<Book> dataSet = service.selectBookList();
    List<Repayment> queryall = repaymentMapper.queryall();
    String resultUrl="E:\\book1.xls";
    String pattern="yyyy-MM-dd";
    ExportExcel.exportExcel(sheetName, titleName, headers, queryall, resultUrl, pattern);

    return "success";
}