How to remove all white spaces in java [duplicate]

Question

java.lang.String class has method substring not substr , thats the error in your program.

Moreover you can do this in one single line if you are ok in using regular expression.

a.replaceAll("\\s+","");

Why not use a regex for this?

a = a.replaceAll("\\s","");

In the context of a regex, \s will remove anything that is a space character (including space, tab characters etc). You need to escape the backslash in Java so the regex turns into \\s. Also, since Strings are immutable it is important that you assign the return value of the regex to a.

The most intuitive way of doing this without using literals or regular expressions:

yourString.replaceAll(" ","");

Replace all the spaces in the String with empty character.

String lineWithoutSpaces = line.replaceAll("\\s+","");