csv文件其实就是格式化的txt文件

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csv文件其实就是格式化的txt文件，所以操作和txt文件差不多，直接上代码了：

<dependency><groupId>commons-lang</groupId><artifactId>commons-lang</artifactId><version>2.5</version></dependency> <dependency><groupId>org.ostermiller</groupId><artifactId>utils</artifactId><version>1.07.00</version></dependency>

import java.io.File;import java.io.FileOutputStream;import java.io.FileWriter;import java.io.IOException;import java.util.Date;import org.apache.commons.lang.time.DateFormatUtils;import com.Ostermiller.util.CSVPrint;import com.Ostermiller.util.CSVPrinter;/** *  * @author alex.wang * csv文件写入 * */public class CsvFilePrinter{         private CSVPrint csvPrint;    /**     *      * @param fileName 文件路径     * @param append 是否支持追加     * @throws IOException     */    public CsvFilePrinter(String fileName,boolean append) throws IOException {     File file = new File(fileName);    if(!file.exists()){    csvPrint = new CSVPrinter(new FileWriter(fileName,append));    init();    }else{    csvPrint = new CSVPrinter(new FileWriter(fileName,append));    if(!append){                init();    }    }         }        public void init() throws IOException{    write(new String[]{"id","mac","val","date"});    }       public void write(String[] values) throws IOException {      csvPrint.writeln(values);    }          public static void main(String[] args) throws Exception {       String csvFile = "demo".concat("-").concat(DateFormatUtils.format(new Date(), "yyyyMMdd")).concat(".csv");        CsvFilePrinter print = new CsvFilePrinter(csvFile,false);                for(int i=0;i<10;i++){        print.write(new String[]{"50001"+i,"C914"+i,Integer.toString(-80+i),DateFormatUtils.format(new Date(), "yyyy-MM-dd")});        }        }     }

import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;import com.Ostermiller.util.ExcelCSVParser;import com.Ostermiller.util.LabeledCSVParser;/** *  * @author alex.wang * csv文件解析器 * */public class CsvFileParser{         private LabeledCSVParser csvParser;//csv解析器，对于第一行的表头信息，自动加载为索引关键字         private int currLineNum = -1;//文件所读到行数         private String[] currLine = null;//用来存放当前行的数据             /*      *  构造函数，      *  Param: in InputStream 要解析的信息流      *  throws IOException      */          public CsvFileParser(InputStream in) throws IOException {              csvParser = new LabeledCSVParser(new ExcelCSVParser(in));              currLineNum = csvParser.getLastLineNumber();      }        public CsvFileParser(String fileName) throws IOException {     InputStream in = new FileInputStream(fileName);    csvParser = new LabeledCSVParser(new ExcelCSVParser(in));          currLineNum = csvParser.getLastLineNumber();     }        /*      * 检查是否还有数据      *      * return ture 还有一行数据，false 没有数据      */      public boolean hasMore() throws IOException {          currLine = csvParser.getLine();          currLineNum = csvParser.getLastLineNumber();          if (null == currLine)              return false;          return true;      }         /*      * 返回当前行数据，关键字所指向的数据      * param:String filedName 该行的表头      * return:String 返回当前行数据，关键字所指向的数据      */      public String getByFieldName(String fieldName) {          return csvParser.getValueByLabel(fieldName);      }         /*      * 关闭解析器      *      *       */      public void close() throws IOException {          csvParser.close();       }         /*      * 读取当前行数据      *      *  return String[] 读取当前行数据      */      public String[] readLine() throws IOException {          currLine = csvParser.getLine();           currLineNum = csvParser.getLastLineNumber();           return currLine;      }        public int getCurrLineNum(){            return currLineNum;      }          public static void main(String[] args) throws Exception {              //创建解析信息流          InputStream in=new FileInputStream(new File("demo.csv"));            //实例解析器CsvFileParser           CsvFileParser parser=new CsvFileParser(in);            //读取数据          while(parser.hasMore()){                           System.out.print(parser.getByFieldName("time")+" ");//time 系表头数据              System.out.print(parser.getByFieldName("total")+" ");                       }                   parser.close();                  }     }

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