POI以SAX方式解析Excel2007大文件(包含空单元格的处理) Java生成CSV文件实例详解

package com.saicfc.pmpf.internal.manage.utils;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletResponse;

import org.apache.commons.beanutils.BeanUtils;

/**
 * 文件操作
 */
public class CSVUtils {

    /**
     * 生成为CVS文件
     * 
     * @param exportData 源数据List
     * @param map csv文件的列表头map
     * @param outPutPath 文件路径
     * @param fileName 文件名称
     * @return
     */
    @SuppressWarnings("rawtypes")
    public static File createCSVFile(List exportData, LinkedHashMap map, 
            String outPutPath, String fileName) {
        File csvFile = null;
        BufferedWriter csvFileOutputStream = null;
        try {
            File file = new File(outPutPath);
            if (!file.exists()) {
                file.mkdir();
            }
            // 定义文件名格式并创建
            csvFile = File.createTempFile(fileName, ".csv", new File(outPutPath));
            System.out.println("csvFile：" + csvFile);
            // UTF-8使正确读取分隔符","
            csvFileOutputStream = new BufferedWriter(
                    new OutputStreamWriter(
                            new FileOutputStream(csvFile), "UTF-8"),1024);
            System.out.println("csvFileOutputStream：" + csvFileOutputStream);
            // 写入文件头部
            for (Iterator propertyIterator = map.entrySet().iterator(); 
                    propertyIterator.hasNext();) {
                java.util.Map.Entry propertyEntry = 
                        (java.util.Map.Entry) propertyIterator.next();
                csvFileOutputStream.write(
                        "" + (String) propertyEntry.getValue() != null ?
                                (String) propertyEntry.getValue() : "" + "");
                if (propertyIterator.hasNext()) {
                    csvFileOutputStream.write(",");
                }
            }
            csvFileOutputStream.newLine();
            // 写入文件内容
            for (Iterator iterator = exportData.iterator(); iterator.hasNext();) {
                Object row = (Object) iterator.next();
                for (Iterator propertyIterator = map.entrySet().iterator(); 
                        propertyIterator.hasNext();) {
                    java.util.Map.Entry propertyEntry = 
                            (java.util.Map.Entry) propertyIterator.next();
                    csvFileOutputStream.write((String) BeanUtils.getProperty(
                            row, (String) propertyEntry.getKey()));
                    if (propertyIterator.hasNext()) {
                        csvFileOutputStream.write(",");
                    }
                }
                if (iterator.hasNext()) {
                    csvFileOutputStream.newLine();
                }
            }
            csvFileOutputStream.flush();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                csvFileOutputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return csvFile;
    }

    /**
     * 下载文件
     * 
     * @param response
     * @param csvFilePath 文件路径
     * @param fileName 文件名称
     * @throws IOException
     */
    public static void exportFile(HttpServletResponse response, 
            String csvFilePath, String fileName)
            throws IOException {
        response.setContentType("application/csv;charset=UTF-8");
        response.setHeader("Content-Disposition", "attachment; filename=" + 
                    URLEncoder.encode(fileName, "UTF-8"));

        InputStream in = null;
        try {
            in = new FileInputStream(csvFilePath);
            int len = 0;
            byte[] buffer = new byte[1024];
            response.setCharacterEncoding("UTF-8");
            OutputStream out = response.getOutputStream();
            while ((len = in.read(buffer)) > 0) {
                out.write(new byte[] { (byte) 0xEF, (byte) 0xBB, (byte) 0xBF });
                out.write(buffer, 0, len);
            }
        } catch (FileNotFoundException e) {
            System.out.println(e);
        } finally {
            if (in != null) {
                try {
                    in.close();
                } catch (Exception e) {
                    throw new RuntimeException(e);
                }
            }
        }
    }

    /**
     * 删除该目录filePath下的所有文件
     * 
     * @param filePath 文件目录路径
     */
    public static void deleteFiles(String filePath) {
        File file = new File(filePath);
        if (file.exists()) {
            File[] files = file.listFiles();
            for (int i = 0; i < files.length; i++) {
                if (files[i].isFile()) {
                    files[i].delete();
                }
            }
        }
    }

    /**
     * 删除单个文件
     * 
     * @param filePath 文件目录路径
     * @param fileName 文件名称
     */
    public static void deleteFile(String filePath, String fileName) {
        File file = new File(filePath);
        if (file.exists()) {
            File[] files = file.listFiles();
            for (int i = 0; i < files.length; i++) {
                if (files[i].isFile()) {
                    if (files[i].getName().equals(fileName)) {
                        files[i].delete();
                        return;
                    }
                }
            }
        }
    }

    /**
     * 测试数据
     * 
     * @param args
     */
    @SuppressWarnings({ "rawtypes", "unchecked" })
    public static void main(String[] args) {
        List exportData = new ArrayList<Map>();
        Map row1 = new LinkedHashMap<String, String>();
        row1.put("1", "11");
        row1.put("2", "12");
        row1.put("3", "13");
        row1.put("4", "14");
        exportData.add(row1);
        row1 = new LinkedHashMap<String, String>();
        row1.put("1", "21");
        row1.put("2", "22");
        row1.put("3", "23");
        row1.put("4", "24");
        exportData.add(row1);
        LinkedHashMap map = new LinkedHashMap();
        map.put("1", "第一列");
        map.put("2", "第二列");
        map.put("3", "第三列");
        map.put("4", "第四列");

        String path = "c:/export/";
        String fileName = "文件导出";
        File file = CSVUtils.createCSVFile(exportData, map, path, fileName);
        String fileName2 = file.getName();
        System.out.println("文件名称：" + fileName2);
    }
}

　　public static void main(String[] args) {
        String name = "银行退款数据";
        List exportData = new ArrayList();
        LinkedHashMap datamMap = null;
        for (Iterator iterator = refundList.iterator(); iterator.hasNext();) {
            HashMap map = (HashMap) iterator.next();
            datamMap = new LinkedHashMap();
            datamMap.put("1", map.get("merOrderId"));
            datamMap.put("2", DateUtil.convertDateToString("yyyyMMdd", 
                    (Date) map.get("orderTime")));
            BigDecimal amount = (BigDecimal) map.get("amount");
            String amountString = amount.divide(new BigDecimal(10)).toPlainString();
            datamMap.put("3", amountString);
            datamMap.put("4", map.get("remark") != null ? map.get("remark") : "");
            exportData.add(datamMap);
        }
        LinkedHashMap map = new LinkedHashMap();
        map.put("1", "订单号");
        map.put("2", "支付日期");
        map.put("3", "退货现金金额（整数金额 单位：分）");
        map.put("4", "退货原因");
        File file = CSVUtils.createCSVFile(exportData, map, filePath, name);// 生成CSV文件
        fileName = file.getName();
        CSVUtils.exportFile(response, filePath + fileName, fileName);// 下载生成的CSV文件
    }