Split string into character array

Question

I need to split String into an array of strings with one character.

For example, splitting "cat" will give an array of "c", "a", "t"

Answer 1

"cat".split("(?!^)") 

This will create

array ["c", "a", "t"]

Answer 2

 "cat".toCharArray() 

But if you need strings

 "cat".split("") 

Edit: this will return an empty first value.

Answer 3

 String str = "cat"; char[] cArray = str.toCharArray(); 

Answer 4

Take a look at the String class of the getChars () method .

Answer 5

An efficient way to turn String into an array of single-character strings would be to do this:

 String[] res = new String[str.length()]; for (int i = 0; i < str.length(); i++) { res[i] = Character.toString(str.charAt(i)); } 

However, this does not take into account the fact that a char in String can actually represent half the Unicode code point. (If the code point is not in BMP.) To deal with this, you need to iterate through the code points ... which is more complicated.

This approach will be faster than using String.split(/* clever regex*/) , and it will probably be faster than using Java 8+ threads. Most likely this is faster:

 String[] res = new String[str.length()]; int 0 = 0; for (char ch: str.toCharArray[]) { res[i++] = Character.toString(ch); } 

because toCharArray must copy the characters into a new array.

Answer 6

If the input contains characters outside the Basic Multilingual Plane (some CJK characters, new emoji ...), approaches like "a💫b".split("(?!^)") Cannot be used because they break such characters (results on array ["a", "?", "?", "b"] ), and you need to use something more secure:

 "a💫b".codePoints() .mapToObj(cp -> new String(Character.toChars(cp))) .toArray(size -> new String[size]); 

Answer 7

Perhaps you can use a for loop that goes through the contents of the String, and extract characters with characters using the charAt method.

In combination with ArrayList<String> , for example, you can get your array of individual characters.

Answer 8

 for(int i=0;i<str.length();i++) { System.out.println(str.charAt(i)); }