Java：创建具有输入/输出的分隔符​​方法

Question

我正在从班级研究问题，基本上它会读取一个字符串和一个字符。角色是分隔符。然后，它将在字符串中搜索分隔符，并创建一个与查找分隔符的次数相等的数组。然后它将每个字符或字符串分配给数组中自己的位置并返回它。

也许我在思考问题，但其唯一的好处就是不依赖各种字符串方法并创建自己的方法。我怎样才能让这个方法只将在读取的字符串中找到的字符串/ char分配给数组中的一个位置而不是全部，以及阻止它添加不必要的输出？帮助/建议非常感谢

public static String[] explode(String s, char d){
    String []c;
    int count = 1;
    //checks to see how many times the delimter appears in the string and creates an      array of corresponding size
    for(int i = 0; i < s.length(); i++){
        if(d == s.charAt(i))
            count ++;
    }
    c = new String [count];
    //used for checking to make sure the correct number of elements are found
    System.out.println(c.length);
    //goes through the the input string "s" and checks to see if the delimiter is found
    //when it is found it makes c[j] equal to what is found
    //once it has cycled through the length of "s" and filled each element for c, it returns the array
    for(int i = 0; i < s.length(); i++){
            for(int j = 0; j < c.length; j++){
                if(d == s.charAt(i))
                    c[j] += s.substring(i-1);
            }
    }
    //provides output for the array [c] just to verify what was found
    for(int y = 0; y < c.length; y++)
        System.out.println(c[y]);
    return c;
}
public static void main(String [] args){
    String test = "a,b,c,d";
    char key = ',';
    explode(test,key);
}


    ^The following will output:
    4
    nulla,b,c,db,c,dc,d
    nulla,b,c,db,c,dc,d
    nulla,b,c,db,c,dc,d
    nulla,b,c,db,c,dc,d

    I'm aiming for:
    4
    a
    b
    c
    d

谢谢

Answer 1

也许你可以尝试这样的事情：

public static void main(String[] args){
    explode("a,b,c,d", ',');
}

public static void explode(final String string, final char delimiter){
    int length = 1;
    for(final char c : string.toCharArray())
        if(delimiter == c)
            length++;
    if(length == 1)
        return;
    final String[] array = new String[length];
    int index, prev = 0, i = 0;
    while((index = string.indexOf(delimiter, prev)) > -1){
        array[i++] = string.substring(prev, index);
        prev = index+1;
    }
    array[i] = string.substring(prev);
    System.out.println(length);
    for(final String s : array)
        System.out.println(s);
}

上述程序的输出是：

4

a

b

c

d

或者，如果您想使用List<String>代替（和Java 8），可以通过执行以下操作来删除几行：

public static void explode(final String string, final char delimiter){
    final List<String> list = new LinkedList<>();
    int index, prev = 0;
    while((index = string.indexOf(delimiter, prev)) > -1){
        list.add(string.substring(prev, index));
        prev = index+1;
    }
    list.add(string.substring(prev));
    System.out.println(list.size());
    list.forEach(System.out::println);
}