java 匯出csv格式（支援list的實體類）
阿新 • • 發佈：2019-01-04
做的網頁專案，要匯出pdf使用itext工具，要是excel就使用jxl的jar包，匯出csv格式的話，就可以使用如下工具類，參考的博主是http://blog.csdn.net/xuxu198899223/article/details/38079885?utm_source=tuicool&utm_medium=referral，他支援傳入的資料是map的形式的，實際在專案中不太常用，一般都是實體類的Arraylist形式，這樣支援擴充套件，如下我在他的基礎上修改的程式碼（保留他原來的程式碼）：
1.實體類：
2.工具類，匯出csv格式：/** * * @author ALLONE * */ public class BankWageMonth { private String id;// private String number;// public String getId() { return id; } public void setId(String id) { this.id = id; } public String getNumber() { return number; } public void setNumber(String number) { this.number = number; } }
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.lang.reflect.Method; 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 jxl.write.Label; import org.apache.commons.beanutils.BeanUtils; /** * 檔案操作 * * @author qiulinhe * @version 2016年12月23日14:21:39 */ public class CsvUtil { /** * 生成為CVS檔案 * * @param exportData * 源資料List * @param fileds * @param map * csv檔案的列表頭map * @param outPutPath * 檔案路徑 * @param fileName * 檔名稱 * @return */ @SuppressWarnings("rawtypes") public static File createCSVFile(List exportData, String[] fileds, LinkedHashMap map, String outPutPath, String fileName) { File csvFile = null; BufferedWriter csvFileOutputStream = null; try { File file = new File(outPutPath); if (!file.exists()) { file.mkdir(); } // 定義檔名格式並建立 csvFile = File.createTempFile(fileName, ".csv", new File(outPutPath)); System.out.println("csvFile：" + csvFile); // UTF-8使正確讀取分隔符"," csvFileOutputStream = new BufferedWriter(new OutputStreamWriter( new FileOutputStream(csvFile), "GBK"), 1024); System.out.println("csvFileOutputStream：" + csvFileOutputStream); // 寫入檔案頭部 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 ? new String( ((String) propertyEntry.getValue()) .getBytes("GBK"), "GBK") : ""); if (propertyIterator.hasNext()) { csvFileOutputStream.write(","); } System.out.println(new String(((String) propertyEntry .getValue()).getBytes("GBK"), "GBK")); } csvFileOutputStream.write("\r\n"); // 寫入檔案內容, // ============ //第一種格式：Arraylist<實體類>填充實體類的基本資訊================== for (int j = 0; exportData != null && !exportData.isEmpty() && j < exportData.size(); j++) { BankWageMonth t = (BankWageMonth) exportData.get(j); Class clazz = t.getClass(); String[] contents = new String[fileds.length]; for (int i = 0; fileds != null && i < fileds.length; i++) { String filedName = toUpperCaseFirstOne(fileds[i]); Method method = clazz.getMethod(filedName); method.setAccessible(true); Object obj = method.invoke(t); String str = String.valueOf(obj); if (str == null || str.equals("null")) str = ""; contents[i] = str; } for (int n = 0; n < contents.length; n++) { // 將生成的單元格新增到工作表中 csvFileOutputStream.write(contents[n]); csvFileOutputStream.write(","); } csvFileOutputStream.write("\r\n"); } // ============ //第二種格式：Arraylist<map>填充實體類的基本資訊================== // 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()) != null ? (String) // propertyEntry // .getKey() : "")); // if (propertyIterator.hasNext()) { // csvFileOutputStream.write(","); // } // } // if (iterator.hasNext()) { // csvFileOutputStream.write("\r\n"); // } // } // ================================= csvFileOutputStream.flush(); } catch (Exception e) { e.printStackTrace(); } finally { try { csvFileOutputStream.close(); } catch (IOException e) { e.printStackTrace(); } } return csvFile; } /** * 下載檔案 * * @param response * @param csvFilePath * 檔案路徑 * @param fileName * 檔名稱 * @throws IOException */ public static void exportFile(HttpServletResponse response, String csvFilePath, String fileName) throws IOException { response.setContentType("application/csv;charset=GBK"); response.setHeader("Content-Disposition", "attachment; filename=" + new String(fileName.getBytes("GBK"), "ISO8859-1")); // URLEncoder.encode(fileName, "GBK") InputStream in = null; try { in = new FileInputStream(csvFilePath); int len = 0; byte[] buffer = new byte[1024]; response.setCharacterEncoding("GBK"); 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); } } } } /** * 刪除該目錄filePath下的所有檔案 * * @param filePath * 檔案目錄路徑 */ 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(); } } } } /** * 刪除單個檔案 * * @param filePath * 檔案目錄路徑 * @param fileName * 檔名稱 */ 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; } } } } } /** * 測試資料 * * @param args */ @SuppressWarnings({ "rawtypes", "unchecked" }) public static void main(String[] args) { // 獲取農商銀行的資料:true代表是農商 // =======改成list的格式，支援（Arraylist傳入實體類的形式），改造的方法============ ArrayList<BankWageMonth> bankWageList = new ArrayList<BankWageMonth>(); BankWageMonth bankWage = new BankWageMonth(); bankWage.setId("123"); bankWage.setNumber("2016rz0001"); BankWageMonth bankWage2 = new BankWageMonth(); bankWage2.setId("124"); bankWage2.setNumber("2016rz0002"); bankWageList.add(bankWage); bankWageList.add(bankWage2); // =======改成list的格式(支援map的形式），原作者的方法============ // 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 = "D://export//"; String fileName = "檔案匯出"; String fileds[] = new String[] { "id", "number" };// 設定列英文名（也就是實體類裡面對應的列名） File file = CsvUtil.createCSVFile(bankWageList, fileds, map, path, fileName); String fileName2 = file.getName(); System.out.println("檔名稱：" + fileName2); } /** * 將第一個字母轉換為大寫字母並和get拼合成方法 * * @param origin * @return */ private static String toUpperCaseFirstOne(String origin) { StringBuffer sb = new StringBuffer(origin); sb.setCharAt(0, Character.toUpperCase(sb.charAt(0))); sb.insert(0, "get"); return sb.toString(); } }