Java:我的 split 方法有问题

Question

我正在尝试创建一个 split 方法，将从输入文件中读取的行拆分为我返回的字符串数组。问题是，当我通过 for 循环发送诸如“ho;hi hello”之类的行时，它总是在第一个分隔符或 ";" 之后停止。或第一个运算符，例如 "+" 。我不确定为什么要这样做，因为我希望它继续迭代直到行尾，这意味着在 if 语句之后再次迭代 for 循环，直到 i < line.length()

If String line =="ho;hi hello" 

我想要打印出来

This is the string in location 0: ho
This is the string in location 1: ;
This is the string in location 2: hi
This is the string in location 3: hello

目前只是打印出来

This is the string in location 0: ho
This is the string in location 1: ;

始终停在第一个分隔符或运算符处。这是 split 方法的代码。

private static String[] split(String line) {

    String temp = "";           //var to store each line from input temporarily 
    boolean flag = false;       //var to check if "\" is in the from input
    char[] lineCharArray = line.toCharArray(); //transforms line into array of chars  
    List<String> array = new ArrayList<String>(); //ArrayList to store the split strings temporarily

    for (int i = 0; i<line.length(); i++){
        if (!isDelimiter(lineCharArray[i]) && !isOperator(lineCharArray[i]) && flag==false){
            //System.out.println(lineCharArray[i]);
            temp += lineCharArray[i];
        } else {
            array.add(temp);
            if (isDelimiter(lineCharArray[i])) {
                array.add( String.valueOf(lineCharArray[i])); 
            }
            if (isOperator(lineCharArray[i])) {
                array.add( String.valueOf(lineCharArray[i])); 
            }
        }
    }


    String [] strings = new String[array.size()]; //string that is returned for lexical analysis
    array.toArray( strings );
    for (int i = 0; i<strings.length; i++) {
        System.out.println("This is the string in location " + i + ": " + strings[i]);
    }
    return strings;
}


  private static boolean isDelimiter(char c) {
     char [] delimiters = {':', ';', '}','{', '[',']','(',')',','};
     for (int x=0; x<delimiters.length; x++) {
      if (c == delimiters[x]) return true;      
     }
     return false;
  }

  private static boolean isOperator(char o) {
     char [] operators = {'+', '-', '*','/', '%','<','>','=','!','&','|'};
     for (int x=0; x<operators.length; x++) {
      if (o == operators[x]) return true;      
     }
     return false;
  }

Answer 1

我在这里发现了 3 个问题。

1. 空格不是分隔符，因此预期输出将是:

   This is the string in location 0: ho
   This is the string in location 1: ;
   This is the string in location 2: hi hello
   

2. 在向其中添加任何新字符之前，您需要重置 temp。最好使用 StringBuffer 或 StringBuilder。

3. 您还需要将最后一个 temp 添加到数组中。

这里我提供修改后的for循环:

for (int i = 0; i<line.length(); i++){
    if (!isDelimiter(lineCharArray[i]) && !isOperator(lineCharArray[i]) && flag==false){
        //System.out.println(lineCharArray[i]);
        temp += lineCharArray[i];
    } else {
        array.add(temp);
        // Resetting temp variable.
        temp = "";
        if (isDelimiter(lineCharArray[i])) {
            array.add( String.valueOf(lineCharArray[i]));
        }
        if (isOperator(lineCharArray[i])) {
            array.add( String.valueOf(lineCharArray[i]));
        }
    }
}
// Adding last temp to the array.
array.add(temp);