CODEWITHSUNDEEP
java
user6050545
user6050545

Reputation: 35

line ending with Multiple underscores

Could you please let me know how to check whether the line ending with multiple underscores.

am able to check whether string ends with underscore but not able to get the count of number of underscores at the end of line.

Based on the underscores count i need to assign localNumberOfColumns

if(line.endsWith("_")){
    localNumberOfColumns=NumberOfColumns-1;
}else{
    localNumberOfColumns=NumberOfColumns;
}

Upvotes: 2

Views: 295

Answers (2)

Robby Cornelissen
Robby Cornelissen

Reputation: 97322

You can split() of all final underscores, and then compare the length of the original input with the length of the input with the underscores removed:

 String s = "abc123___";
 String sWithoutUnderscores = s.split("_*$")[0];
 int numberOfUnderscores = s.length() - sWithoutUnderscores.length();

Update

As pointed out in the comments, above solution fails for cases where the string contains only underscores. If that is a possibility in your domain, consider using Java's pattern matching utilities:

String s = "abc123___";
Matcher matcher = Pattern.compile("_*$").matcher(s);
int numberOfUnderscores = matcher.find() ? matcher.group().length() : 0;

Upvotes: 2

Tim Biegeleisen
Tim Biegeleisen

Reputation: 522501

What first came to mind for me was simply comparing the length of your input string against the length of your string with all final underscores removed.

String threeUS = "abc123___";
int numUS = threeUS.length() - threeUS.replaceAll("(?:_)*$", "").length();
System.out.println("Number of underscores: " + numUS);

Output:

Number of underscores: 3

Demo here:

Rextester

Upvotes: 2

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