Java无效的数组大小

Question

I taking a string input from console . If I input "abcd" and spilt like this way

Scanner input = new Scanner(System.in);
String[]stringInput = input.nextLine().toLowerCase().trim().split("");

Suppose, I have entered "abcd" as input, stringInput.length is showing 5 . But, It should be 4 right ? What's wrong, I am doing here ? Any idea ? How can I solve that ?

Answer 1

There is an empty String at the end.

Use split("", -1)

...., the array can have any length, and trailing empty strings will be discarded

Answer 2

Using split("") there always be an extra empty element of array at the first index

to be sure, you can try:

System.out.println(Arrays.toString(stringInput));

Output:

[, a, b, c, d]

Answer 3

在字符串之后总是有一个空的空间。所以你需要在你的情况下使用abcd和空格

Use split("", -1)

Answer 4

You can achieve it using regex in split method as follows:

split("(?!^)")

See more details on regex usage.