Chris,
String::stripIndent might not be the routine you are looking for. It is
provided to duplicate the actions performed by the compiler when processing a
Text Block. To use String::stripIndent as a method to strip indentation in the
way you might expect you might have to massage the input string.
Note: using ····· to represent leading spaces
To understand what is going on, reverse the process and image what the string
looked like as a Text Block.
The first case goes like this.
String endsWithNewLine = """
\s\s\s\s\s<- this line starts with 5 blank spaces.
\s\s\s\s\s<- count again: 1, 2, 3, 4, 5
········""";
String endsWithNewLineAfterStripIndent = """
·····<- this line starts with 5 blank spaces.
·····<- count again: 1, 2, 3, 4, 5
""";
In this case the first two lines start with 5 spaces and the last line has zero
spaces because we stripped trailing spaces.
So applying the rules, the last line dominates and the indentation doesn't
change.
·····<- this line starts with 5 blank spaces.
·····<- count again: 1, 2, 3, 4, 5
The last line still has zero spaces.
The second case goes like this.
String endsWithAsterisk = """
·····\s\s\s\s\s<- this line starts with 5 blank spaces.
·····\s\s\s\s\s<- count again: 1, 2, 3, 4, 5
········*""";
String endsWithAsteriskAfterStripIndent = """
<- this line starts with 5 blank spaces.
<- count again: 1, 2, 3, 4, 5
···*""";
Since there was no stripping of all characters on the last line, first two
lines dominate and we get
<- this line starts with 5 blank spaces.
<- count again: 1, 2, 3, 4, 5
···*
So it all comes down to the last line being blank or not blank. A blank line
becomes an empty line due to stripping of trailing blanks.
Cheers,
-- Jim
> On Jan 12, 2020, at 12:26 AM, Chris T <tech.mesh...@gmail.com> wrote:
>
> Hi,
>
> I am working on an educational material about OpenJDK 14. Downloaded the
> code, compiled it and while "playing" with the new features I found
> something that seems to be inconsistent (maybe a bug?). So here we go:
>
> I defined this method:
> public void questionToOpenJDKPossibleBugOnStripIdent() {
>
> String endsWithNewLine = """
> \s\s\s\s\s<- this line starts with 5 blank spaces.
> \s\s\s\s\s<- count again: 1, 2, 3, 4, 5
> """;
> System.out.println("The string ending with new lines looks like this:");
> System.out.println(endsWithNewLine);
>
> System.out.println();
> System.out.println("If we call stripIndent, the white spaces are not
> eliminated (maybe I misunderstand the concept of incidental white space):");
> System.out.println(endsWithNewLine.stripIndent());
>
> String endsWithAsterisk = """
> \s\s\s\s\s<- this line starts with 5 blank spaces.
> \s\s\s\s\s<- count again: 1, 2, 3, 4, 5
> *""";
> System.out.println("The string ending with asterisk looks like this:");
> System.out.println(endsWithAsterisk);
>
> System.out.println();
> System.out.println("If we call stripIndent, the white spaces ARE
> eliminated (this seems to be inconsistent with the previous behaviour):");
> System.out.println(endsWithAsterisk.stripIndent());
> }
>
> If I run the code above, I get this output:
> The string ending with new lines looks like this:
> <- this line starts with 5 blank spaces.
> <- count again: 1, 2, 3, 4, 5
>
>
> If we call stripIndent, the white spaces are not eliminated (maybe I
> misunderstand the concept of incidental white space):
> <- this line starts with 5 blank spaces.
> <- count again: 1, 2, 3, 4, 5
>
> The string ending with asterisk looks like this:
> <- this line starts with 5 blank spaces.
> <- count again: 1, 2, 3, 4, 5
> *
>
> If we call stripIndent, the white spaces ARE eliminated (this seems to be
> inconsistent with the previous behaviour):
> <- this line starts with 5 blank spaces.
> <- count again: 1, 2, 3, 4, 5
> *
>
> I looked over the stripIdent code and found this line (which, after
> debugging, turns out that "blocks" the entire indentation process):
> boolean optOut = lastChar == '\n' || lastChar == '\r';
>
> Can somebody explain me what am I missing? Maybe there is an area din the
> JEP documentation that clarifies this and I didn't see nor actively paid
> attention to?
>
> Thanks!
> Chris T
