nextLine 值的 Java 扫描器定界符

Question

我有一个 .dat 格式的文件。这是一个示例

||= (N ) =|| 1|| 0.938 || --- || 0.5 || (****)|| 0.5 || 0 || 0 || 0 || 0.700 || (p)=2212, (n)=2112 ||

||= (\Delta ) =|| 2|| 1.232 || 0.118 || 1.5 || (****)|| 1.5 || 0 || 0 || 3 || 1.076 || (\Delta^{++})=2224, (\Delta^+)=2214, (\Delta^0)=2114, (\Delta^-)=1114 ||

||= (P_{11}(1440) ) =|| 3|| 1.462 || 0.391 || 0.5 || (****)|| 0.5 || 0 || 0 || 3 || 1.076 || 202212, 202112 ||

||= (S_{11}(1535) ) =|| 4|| 1.534 || 0.151 || 0.5 || ( ***)|| 0.5 || 0 || 0 || 3 || 1.076 || 102212, 102112 ||

我正在尝试使用 Scanner 读取此文件并用“||”分隔该行然后发送到 ArrayList 以供将来处理。这是我使用定界符的代码示例

String file = "data.dat";
Scanner s = null;
try {
    s = new Scanner(new File(file)).useDelimiter("\\|\\|"); //here is the use of my delimiter

    ArrayList<String> list = new ArrayList<String>();
    while (s.hasNextLine()) {   //notice I am using hasNextLine because each line must be unique to create the HashMap 
        list.add(s.nextLine());
    }
    s.close();
    for (String string : list) {  //Lets print out the values of the list
        System.out.println(string);
    }
} catch (FileNotFoundException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
} 

但我的输出仍然有分隔符的值，即输出如下:

||= (N ) =|| 1|| 0.938 || --- || 0.5 || (****)|| 0.5 || 0 || 0 || 0 || 0.700 || (p)=2212, (n)=2112 ||

||= (\Delta ) =|| 2|| 1.232 || 0.118 || 1.5 || (****)|| 1.5 || 0 || 0 || 3 || 1.076 || (\Delta^{++})=2224, (\Delta^+)=2214, (\Delta^0)=2114, (\Delta^-)=1114 ||

||= (P_{11}(1440) ) =|| 3|| 1.462 || 0.391 || 0.5 || (****)|| 0.5 || 0 || 0 || 3 || 1.076 || 202212, 202112 ||

||= (S_{11}(1535) ) =|| 4|| 1.534 || 0.151 || 0.5 || ( ***)|| 0.5 || 0 || 0 || 3 || 1.076 || 102212, 102112 ||

我已经搜索过，但没有找到有用的答案。我还看到一条关于“资源泄漏:''永远不会关闭”的警告，其中包含以下行

s = new Scanner(new File(file)).useDelimiter("\\|\\|");

如果线被打断，它就会消失

s = new Scanner(new File(file));
s.useDelimiter("\\|\\|");

感谢任何帮助。

Answer 1

您不需要使用反斜杠转义。而不是 \\|\\| 作为分隔符，只需在从文件中读取字符串后拆分它即可。

String file = "data.dat";
Scanner s = null;
try {
    s = new Scanner(new File(file)); //no more delimiter. It's not needed
    ArrayList<String> list = new ArrayList<String>();
    while (s.hasNextLine()) {

        String[] strings = s.nextLine().split("[||]");
        for (int i = 0; i < strings.length; i++) {
            list.add(strings[i]);   
        }
    }
    s.close();
    for (String string : list) {  //Lets print out the values of the list
        System.out.println(string);
    }
} catch (FileNotFoundException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
} 

这应该可以解决它。