采用commons-csv数据转CSV文件

采用commons-csv数据转CSV文件

• 导入pom.xml依赖

      <dependency>
          <groupId>org.apache.commons</groupId>
          <artifactId>commons-csv</artifactId>
          <version>1.5</version>
      </dependency>
  
      <dependency>
          <groupId>org.apache.poi</groupId>
          <artifactId>poi</artifactId>
          <version>3.17</version>
      </dependency>
  
      <dependency>
          <groupId>org.apache.poi</groupId>
          <artifactId>poi-ooxml</artifactId>
          <version>3.17</version>
      </dependency>
  

• 创建工具类CSVUtils

  public class CSVUtils {
  
      //CSV文件分隔符
      private static final String NEW_LINE_SEPARATOR = "\n";
  
      //CSV文件头 可以不用写死
      private static final Object [] FILE_HEADER = {"天气","气温","降水","风速","数据更新时间","对象日期时间"};
  
      /**
       * 写CSV文件
       * @param fileName 文件名
       * @param weather  天气
       */
      public void writeCsvFile(String fileName, Weather weather){
          //获取文件夹名
          String dir = fileName.substring(0,11);
          File dirFile = new File(dir);
          //判断文件是否存在
          if(!dirFile.exists()) {
              dirFile.mkdirs();
          }
          File file=new File(fileName);
          if(!file.exists()) {
              try {
                  file.createNewFile();
              } catch (IOException e) {
                  e.printStackTrace();
              }
          }
          FileWriter fileWriter = null;
          CSVPrinter csvFilePrinter = null;
  
          //创建 CSVFormat
          CSVFormat csvFileFormat = CSVFormat.DEFAULT.withRecordSeparator(NEW_LINE_SEPARATOR);
          SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
          Calendar calendar = Calendar.getInstance();
          try{
              //初始化FileWriter
              fileWriter = new FileWriter(fileName);
  
              //初始化 CSVPrinter
              csvFilePrinter = new CSVPrinter(fileWriter,csvFileFormat);
  
               //创建CSV文件头
              csvFilePrinter.printRecord(FILE_HEADER);
              
              //遍历写进CSV
              List<String>  weatherDataRecord = new ArrayList<>();
              weatherDataRecord.add(weather.getWeather());
              weatherDataRecord.add(weather.getTemp());
              weatherDataRecord.add(weather.getWater());
              weatherDataRecord.add(weather.getWind());
              weatherDataRecord.add(sdf.format(weather.getForcastDate()));
  
              //设置整点时间
              calendar.setTime(weather.getForcastDate());
              calendar.set(Calendar.MINUTE, 0);
              calendar.set(Calendar.SECOND, 0);
              Date time = calendar.getTime();
              weatherDataRecord.add(sdf.format(time));
  
              csvFilePrinter.printRecord(weatherDataRecord);
          }catch (Exception e){
              e.printStackTrace();
          }finally {
              try{
                  fileWriter.flush();
                  fileWriter.close();
                  csvFilePrinter.close();
              }catch (IOException e){
                  e.printStackTrace();
              }
          }
      }
  
  }