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来自CSV的LinkedHashMap未获取所有条目

linkedhashmap treemap hashmap arraylist java

0

Isaac Manzi · 技术社区 · 7 年前

按顺序将CSV文件转换为变量。我一直在尝试读取一个CSV文件,其中包含两列,一个标题,然后是条目列表。

然而,它目前被卡在我的CSV的第5行。以下是当前的读取循环:

public static LinkedHashMap<String, ArrayList<String>> runningOrderMap(String filename) throws IOException {
        LinkedHashMap<String, ArrayList<String>> linkedHashMap = new LinkedHashMap<>(50);
        String currentLine = ""; //init iterator variable
        String[] valuesTMP;
        try {
            bufferedReader = new BufferedReader(new FileReader(filename));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        while((currentLine = bufferedReader.readLine()) != null){
            valuesTMP = currentLine.split(", ");
            ArrayList<String> values = new ArrayList<>();
            String key = valuesTMP[0].split("\t")[0].trim();
            values.add(valuesTMP[0].split("\t")[1].trim());
            for(int i = 1; i < valuesTMP.length; i++){
                values.add(valuesTMP[i]);
                System.out.println(valuesTMP[i]);
                linkedHashMap.put(key, values);
            }
        }
        System.out.println("linked hashmap:"+linkedHashMap.keySet().size());
        return linkedHashMap;
    }

示例数据的格式如下:长度不同的标题、一个选项卡,然后是一个内容条目列表,如下所示:

title   content, content2

title example    content, content2, content3

title example three   content, content2

title example    content, content2

该数据持续约20行,但LinkedHashMap不会超过第5行:

title example two   content

我需要保留数组中的行顺序。

1 回复 | 直到 7 年前

1

2

Ivan Kovbas 7 年前

试着移动线 linkedHashMap.put(key, values); 内部外 for 循环,如下所示:

public static LinkedHashMap<String, ArrayList<String>> runningOrderMap(String filename) throws IOException {
    LinkedHashMap<String, ArrayList<String>> linkedHashMap = new LinkedHashMap<>(50);
    String currentLine = ""; //init iterator variable
    String[] valuesTMP;
    try {
        bufferedReader = new BufferedReader(new FileReader(filename));
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
    while((currentLine = bufferedReader.readLine()) != null){
        valuesTMP = currentLine.split(", ");
        ArrayList<String> values = new ArrayList<>();
        String key = valuesTMP[0].split("\t")[0].trim();
        values.add(valuesTMP[0].split("\t")[1].trim());
        for(int i = 1; i < valuesTMP.length; i++){
            values.add(valuesTMP[i]);
            System.out.println(valuesTMP[i]);
        }
        linkedHashMap.put(key, values); // <--this line was moved out from internal for loop
    }
    System.out.println("linked hashmap:"+linkedHashMap.keySet().size());
    return linkedHashMap;
}

仅当内容有多个部分时才执行循环