Java导出CSV文件

@Test
    public void testWrite() throws Exception {
        FileOutputStream fos = new FileOutputStream("E:/cjsworkspace/cjs-excel-demo/target/abc.csv");
        OutputStreamWriter osw = new OutputStreamWriter(fos,"GBK");

        CSVFormat csvFormat = CSVFormat.DEFAULT.withHeader("姓名","年龄","家乡");
        CSVPrinter csvPrinter = new CSVPrinter(osw,csvFormat);

//        csvPrinter = CSVFormat.DEFAULT.withHeader("姓名","家乡").print(osw);

        for (int i = 0; i < 10; i++) {
            csvPrinter.printRecord("张三",20,"湖北");
        }

        csvPrinter.flush();
        csvPrinter.close();

    }

    @Test
    void testRead()  IOException {
        InputStream is = new FileInputStream("E:/cjsworkspace/cjs-excel-demo/target/abc.csv");
        InputStreamReader isr = new InputStreamReader(is,1)">);
        Reader reader =  BufferedReader(isr);

        CSVParser parser = CSVFormat.EXCEL.withHeader("name","age","jia").parse(reader);
        CSVParser csvParser = CSVParser.parse(reader,CSVFormat.DEFAULT.withHeader("name","jia"));
        List<CSVRecord> list = parser.getRecords();
        for (CSVRecord record : list) {
            System.out.println(record.getRecordNumber()
                    + ":" + record.get("name")
                    + ":" + record.get("age")
                    + ":" + record.get("jia"));
        }

        parser.close();
    }

    /**
     * Parsing an Excel CSV File
     */
    @Test
    void testParse()  Exception {
        Reader reader = new FileReader("C:/Users/Administrator/Desktop/abc.csv");
        CSVParser parser = CSVFormat.EXCEL.parse(reader);
         (CSVRecord record : parser.getRecords()) {
            System.out.println(record);
        }
        parser.close();
    }

    
     * Defining a header manually
     void testParseWithHeader() );
        CSVParser parser = CSVFormat.EXCEL.withHeader("id","name","code").parse(reader);
         (CSVRecord record : parser.getRecords()) {
            System.out.println(record.get("id") + ","
                    + record.get("name") + ","
                    + record.get("code"));
        }
        parser.close();
    }

    
     * Using an enum to define a header
     */
    enum MyHeaderEnum {
        ID,NAME,CODE;
    }

    @Test
    void testParseWithEnum() );
        CSVParser parser = CSVFormat.EXCEL.withHeader(MyHeaderEnum.class (CSVRecord record : parser.getRecords()) {
            System.out.println(record.get(MyHeaderEnum.ID) + ","
                    + record.get(MyHeaderEnum.NAME) + ","
                    + record.get(MyHeaderEnum.CODE));
        }
        parser.close();
    }


    private List<Map<String,String>> recordList = new ArrayList<>();

    @Before
    void init() {
        int i = 0; i < 5; i++) {
            Map<String,String> map = new HashMap<>();
            map.put("name","zhangsan");
            map.put("code","001");
            recordList.add(map);
        }
    }

    @Test
    void writeMuti()  InterruptedException {
        ExecutorService executorService = Executors.newFixedThreadPool(3);
        CountDownLatch doneSignal = new CountDownLatch(2);

        executorService.submit(new exprotThread("E:/0.csv",recordList,doneSignal));
        executorService.submit(new exprotThread("E:/1.csv");
    }

    class exprotThread implements Runnable {

        private String filename;
         list;
         CountDownLatch countDownLatch;

        public exprotThread(String filename,List<Map<String,1)"> list,CountDownLatch countDownLatch) {
            this.filename = filename;
            this.list = list;
            this.countDownLatch = countDownLatch;
        }

        @Override
         run() {
            try {
                CSVPrinter printer = new CSVPrinter(new FileWriter(filename),CSVFormat.EXCEL.withHeader("NAME","CODE"));
                for (Map<String,String> map : list) {
                    printer.printRecord(map.values());
                }
                printer.close();
                countDownLatch.countDown();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

　　/**
     * 测试写100万数据需要花费多长时间
     void testMillion()  Exception {
        int times = 10000 * 10;
        Object[] cells = {"满100减15元","100011",15};

          导出为CSV文件
        long t1 = System.currentTimeMillis();
        FileWriter writer = new FileWriter("G:/test1.csv");
        CSVPrinter printer = CSVFormat.EXCEL.print(writer);
        int i = 0; i < times; i++) {
            printer.printRecord(cells);
        }
        printer.flush();
        printer.close();
        long t2 = System.currentTimeMillis();
        System.out.println("CSV: " + (t2 - t1));

          导出为Excel文件
        long t3 = System.currentTimeMillis();
        XSSFWorkbook workbook =  XSSFWorkbook();
        XSSFSheet sheet = workbook.createSheet();
        ) {
            XSSFRow row = sheet.createRow(i);
            int j = 0; j < cells.length; j++) {
                XSSFCell cell = row.createCell(j);
                cell.setCellValue(String.valueOf(cells[j]));
            }
        }
        FileOutputStream fos = new FileOutputStream("G:/test2.xlsx");
        workbook.write(fos);
        fos.flush();
        fos.close();
        long t4 = System.currentTimeMillis();
        System.out.println("Excel: " + (t4 - t3));
    }

<dependencies>
    dependency>
        groupId>org.apache.commons</artifactId>commons-csvversion>1.5>

    >org.apache.poi>poi>3.17>poi-ooxml>


    >junit>4.12scope>test>
>