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是什么导致java.lang.arrayindexoutofboundsexception以及如何防止它(（26个答案）
6天前关门。
怎样？在此处输入代码将读取的行拆分为多个部分；从输入数据（零件）创建品牌；将品牌添加到此列表中；

ArrayList<String> str1 = new ArrayList<>();
    loadFromFile(file, str1);    
    for (String string : str1) {
        String[] str = string.split(",");
        //EG line of file: B7-2018, BMW 730Li (2018), Harman Kardon, 3.749
        String id,name,sound;
        double price;

        id = str[0];
        name = str[1];
        price = Double.valueOf(str[3]);
         sound = str[2];
        Brands brand = new Brands(id, name, sound, price);
        this.add(brand);  /// this is arraylist of Brands (extends ArrayList Brands)
        //error code: ArrayIndexOutOfBoundsException 
        //I do not understand this