After we split a String via RegEx, how could we get the length of new String?

Question

public class TestString {
public static void main(String[] args) {
    String str = "AaaaABBBBcc&^%adfsfdCCOOkk99876 _haHA";
    String[] upStr = str.split("[a-z0-9&^% _]");
    System.out.println("Printout uppercase");

    for (String outUp : upStr){
        System.out.print(outUp);
    }
    System.out.println("\n" + upStr.length);

The "length" is wrong, so, where does the value comes from? How could we get real length?

    System.out.println("\n Printout lowercase");
    String[] lowStr = str.split("[A-Z0-9&^% _]");
    for (String outLow : lowStr){
        System.out.print(outLow);
    }
    System.out.println("\n" + lowStr.length);

    System.out.println("\n non-English");
    String[] nonEng = str.split("[A-Za-z]");
    for (String outNonEng : nonEng){
        System.out.print(outNonEng);
    }
    System.out.println("\n" + nonEng.length);

So my question is:

The value of the length is incorrect, but where is is comes from?
How could I get correct length of String[]?

I will suggest you to read :- http://stackoverflow.com/a/22259885/1996394 — rock321987, Mar 31 '16 at 09:53
Printout uppercase AABBBBCCOOHA in fact the current length is 12; Printout lowercase aaaccadfsfdkkha non-English &^%99876 _ — WilliamZhu, Mar 31 '16 at 09:53
`length` in this case is the number of items in the array. How come you're talking about "length of new string"? — SamWhan, Mar 31 '16 at 09:54
Base on the Java API: String[] split(String regex) Splits this string around matches of the given regular expression. After we use the "split", it will return a String[] back. — WilliamZhu, Mar 31 '16 at 09:57
Do not split, use `replaceAll("[^A-Z]+", "").length` to check uppercase letter count and `replaceAll("[^a-z]+", "").length` to check lowercase letter count. — Wiktor Stribiżew, Mar 31 '16 at 09:59
Yes, and is it the *length* of the array you're talking about? (Please add the output of your code to make it easier to help you + use `@username` to alert people when you reply ;) — SamWhan, Mar 31 '16 at 10:01

score 0 · Accepted Answer · answered Mar 31 '16 at 14:06

You may want to do it like the following:

public static void main(String[] args) {
        String str = "AaaaABBBBcc&^%adfsfdCCOOkk99876 _haHA";
        String[] upStr = str.replaceAll("[^A-Z]", "").split("(?!^)");
        String[] lowStr = str.replaceAll("[^a-z]", "").split("(?!^)");
        String[] nonEng = str.replaceAll("[A-Za-z]", "").split("(?!^)");
        System.out.println("Printout uppercase");
        printResult(upStr);
        System.out.println("\nPrintout lowercase");
        printResult(lowStr);
        System.out.println("\nPrintout non-English");
        printResult(nonEng);   
    }
public static void printResult(String[] array) {
        for (String outChar : array){
        System.out.print(outChar);
    }
    System.out.println("\n" + array.length);
}

Output:

Printout uppercase
AABBBBCCOOHA
12

Printout lowercase
aaaccadfsfdkkha
15

Printout non-English
&^%99876 _
10

After we split a String via RegEx, how could we get the length of new String?

1 Answers1