java - CSV 阅读器拾取空行

Question

我有一个程序，可以读取 CSV 文件并将第一行和最后一行存储为 JSONObject。我当前的实现是跳过最后一行并读取 null 值作为数据对象。

创建/保存 CSV 文件以消除任何空格或空值的正确方法是什么？

CSV

   TIME_STAMP,TOTAL,APPLES,ORANGES,PEARS,GRAPES,TANGERINES,PINEAPPLES,CARROTS,UNKNOWN 
    7/1/2015 4:00,19474,1736,275,8366,5352,3003,393,349,

代码

String firstLine = "";
String lastLine = "";

int count = 0;
if(reader != null){
    String aux = "";
    String lastLineMinusOne = "";
    while ((aux = reader.readLine()) != null) {
        if(count == 0)firstLine = aux;
            lastLineMinusOne = lastLine;
            lastLine = aux;
            count ++;
        }
        logger.info("Count = " + count);             
        String[] columns = firstLine.split(",");
        String[] data = lastLine.split(",");
        logger.info(firstLine);
        logger.info(lastLine);

日志

    2015-09-28 13:41:42,370 [ajp-0.0.0.0-8009-2] INFO  com.ChartData - Count = 3
    2015-09-28 13:23:27,745 [ajp-0.0.0.0-8009-3] INFO  com.ChartData - TIME_STAMP,TOTAL,APPLES,ORANGES,PEARS,GRAPES,TANGERINES,PINEAPPLES,CARROTS,UNKNOWN
    2015-09-28 13:23:27,745 [ajp-0.0.0.0-8009-3] INFO  com.ChartData -

错误

java.lang.ArrayIndexOutOfBoundsException: 10
    at com.ChartData.getCSV(ChartData.java:75)

第 75 行 -> jObject.put("val", data[i]);

Answer 1

你可以:

1. 读作 described here 时解析行:

   while ((aux = reader.readLine()) != null) {
       String auxTrimmed = aux.replaceAll("(?m)^[ \t]*\r?\n", "");
       // more code
   }
   

2. 如果您总是遇到此问题，请忽略最后一行:

   String[] data = lastLineMinusOne.split(",");
   logger.info(lastLineMinusOne);