我想从 CSV 文件恢复对象。我需要知道扫描仪是否有 2 个下一个值:scanner.hasNext()
问题是我的访问构造函数有两个参数,我需要确保 我的 csv 文件中至少还剩下 2 个。
相关代码如下:
/**
* method to restore a pet from a CSV file.
* @param fileName the file to be used as input.
* @throws FileNotFoundException if the input file cannot be located
* @throws IOException if there is a problem with the file
* @throws DataFormatException if the input string is malformed
*/
public void fromCSV(final String fileName)
throws FileNotFoundException, IOException, DataFormatException
{
FileReader inStream = new FileReader(fileName);
BufferedReader in = new BufferedReader(inStream);
String data = in.readLine();
Scanner scan = new Scanner(data);
scan.useDelimiter(",");
this.setOwner(scan.next());
this.setName(scan.next());
while (scan.hasNext()) {
Visit v = new Visit(scan.next(), scan.next());
this.remember(v);
}
inStream.close();
}
提前致谢
最佳答案
hasNext() 也可以采用一个模式,这提供了一种很好的方法来检查这一点:
String pattern = ".*,.*";
while (scan.hasNext(pattern)) {
...
}
关于Java 扫描器与 2 hasNext(),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/28977021/