Java 13 is coming, so I started studying its new features, one of which is text blocks.
I wrote a simple program
public final class Example {
public static void main(String[] args) {
final String greeting = """Hello
It's me, Andrew!""";
System.out.println(greeting);
}
}
I was expecting to see
Hello
It's me, Andrew!
What I got is a compilation error saying
illegal text block open delimiter sequence, missing line terminator
The context of your text block must start from a new line.
public final class Example {
public static void main(String[] args) {
final String greeting = """
Hello
It's me, Andrew!""";
System.out.println(greeting);
}
}
prints
Hello
It's me, Andrew!
An excerpt from JEP 355: Text Blocks (Preview):
A text block consists of zero or more content characters, enclosed by opening and closing delimiters.
The opening delimiter is a sequence of three double quote characters (
""") followed by zero or more white spaces followed by a line terminator. The content begins at the first character after the line terminator of the opening delimiter.
You don't necessarily have to put a line terminator at the end of your content, though.
The closing delimiter is a sequence of three double quote characters. The content ends at the last character before the first double quote of the closing delimiter.
final String greeting = """
Hello
It's me, Andrew!
""";
would mean
Hello
It's me, Andrew!
<an empty line here>
I find it extremely unclear, so I had to share this with the community.
For the record, a rationale for the decision not to allow content immediately after """ is given here
The reason for this is that text blocks are primarily designed to support multi-line strings, and requiring the initial line terminator simplifies the indentation handling rules
