我在Java中使用apache.commons.csv库。我正在使用以下代码从网页读取CSV文件:
InputStream input = new URL(url).openStream();
Reader reader = new InputStreamReader(input, "UTF-8");
defaultParser = new CSVParser(reader, CSVFormat.DEFAULT);
excelParser = new CSVParser(reader, CSVFormat.EXCEL.withHeader());
defaultParsedData = defaultParser.getRecords();
excelParsedData = excelParser.getRecords();
然而,我在这个库中找不到一种方法可以轻松地将此文件写入我的计算机,以便稍后打开并从中读取。
我尝试了这段代码来保存文件。
String outputFile = savePath+".csv";
CSVPrinter csvFilePrinter = null;
CSVFormat csvFileFormat = CSVFormat.EXCEL.withHeader();
FileWriter fileWriter = new FileWriter(outputFile);
csvFilePrinter = new CSVPrinter(fileWriter, csvFileFormat);
for (CSVRecord csvRecord : excelParser) {
for(String dataPoint: csvRecord){
csvFilePrinter.print(dataPoint);
}
csvFilePrinter.print('\n');
}
fileWriter.flush();
fileWriter.close();
csvFilePrinter.close();
然而,当我使用这段代码尝试读取文件时,什么都没有输出:
InputStream input = new FileInputStream(cvsFilePath);
Reader reader = new InputStreamReader(input, "UTF-8");
CSVParser load = new CSVParser(reader, CSVFormat.EXCEL);
//TEST THAT IT WORKED
java.util.List<CSVRecord> testlist = load.getRecords();
CSVRecord dataPoint = testlist.get(0);
System.out.println("print: " + dataPoint.get(0));
这仅仅打印出 "print: "。如果我添加 。System.out.println("print: " + dataPoint.get(1));
它产生了一个
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 1
当我用记事本打开保存的CSV文件时,会有一个空行,然后是:
2016-03-04,714.98999,716.48999,706.02002,710.890015,1967900,710.890015," ",2016-03-03,718.679993,719.450012,706.02002,712.419983,1956800,712.419983," ",2016-03-02,719.00,720.00,712.00,718.849976,1627800,718.849976,"