java - 从文件读取时的system.arraycopy - java

Question

我需要从文件中读取数据，格式为:int, Name nameClass, String, String, String, Scores [int,int,int,int,int]，例如

150，约翰·史密斯，美国，活跃，专业，3,4,3,4,4

运行代码后出现以下错误

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of range: 1
    at java.lang.String.charAt(String.java:658)
    at f1_final.CompetitorList.processLine(CompetitorList.java:184)
    at f1_final.CompetitorList.readFile(CompetitorList.java:149)
    at f1_final.FileWriterComp.main(FileWriterComp.java:14)

我发现这是因为我试图将 int 复制到字符串。我该如何解决这个问题？

private void processLine(String line)   {
    String compNo = "";

    try {
        String [] parts = line.split(",");
        nameClass compName = new nameClass(parts[1], parts[2]);
        compNo = parts[0];
        compNo = compNo.trim();


        String compCountry = parts[3];
        String compLevel = parts [4];
        String compActive = parts[5];

        int compNumber = Integer.parseInt(compNo);
        int compScoreLength = parts.length-6;
        int cScore[] = new int[compScoreLength];

        System.arraycopy(parts, 6, cScore, 0, compScoreLength);         // this line is causing problems which I wasnt able to fix. The program is unable to read arrays from file.

    //  int[]cScore = new int [compScoreLength];
    //  for(int i=0 ; i< compScoreLength ; i++)
    //          cScore[i] = parts[6].charAt(i)-'0';


        Competitor c = new Competitor(compNumber, compName, compCountry, compLevel, compActive, cScore);
        this.addOneCompetitor(c);
    }

Answer 1

stach 跟踪清楚地表明 java.lang.String.charAt(String.java:658) 中存在异常，该异常是在您取消注释的部分中调用的。看来你取消注释后没有重建。请注意，System.arraycopy() 仅当源数组和目标数组具有相同类型时才有效。

您必须手动转换每个元素:

  int[]cScore = new int [compScoreLength];
  for(int i=0 ; i< compScoreLength ; i++)
          cScore[i] = Integer.parseInt(parts[6 + i]);

在此示例中，您有 parts[6] = "3"、parts[7] = "4"、parts[8] = "3 “，...，它们都是一个 String。