Object obj = engine.The Peabody Set of The North American Indianįor your consideration is an original set of The North American Indian, Edward S. Using "one-dimensional" string literals ScriptEngine engine = new ScriptEngineManager().getEngineByName("js") SELECT `EMP_ID`, `LAST_NAME` FROM `EMPLOYEE_TB` Using a "two-dimensional" block of text String query = """ Using "one-dimensional" string literals String query = "SELECT `EMP_ID`, `LAST_NAME` FROM `EMPLOYEE_TB`\n" + Using a "two-dimensional" block of text String html = """ Using "one-dimensional" string literals String html = "\n" + Accordingly, it would be helpful if the developer had precise control over where newlines appear, and, as a related matter, how much white space appears to the left and right of the "block" of text. One part of a program may be more readable when strings are laid out over multiple lines, but the embedded newline characters may change the behavior of another part of the program.
#Text blocks code#
Just because a string spans multiple lines of source code does not mean that newline characters are desirable in the string. Still, it is impossible to predict the role of every string in Java programs.
In essence, a two-dimensional block of text, rather than a one-dimensional sequence of characters. This design default is at odds with the large number of Java programs where strings are too long to fit comfortably on a single line.Īccordingly, it would improve both the readability and the writability of a broad class of Java programs to have a linguistic mechanism for denoting strings more literally than a string literal - across multiple lines and without the visual clutter of escapes. On the one hand, the Java language recognizes this need by allowing strings of unbounded size and content on the other hand, it embodies a design default that strings should be small enough to denote on a single line of a source file (surrounded by " characters), and simple enough to escape easily. More generally, the need to denote short, medium, and long blocks of text in a Java program is near universal, whether the text is code from other programming languages, structured text representing golden files, or messages in natural languages. The snippet is often difficult to read and arduous to maintain. In Java, embedding a snippet of HTML, XML, SQL, or JSON in a string literal "." usually requires significant editing with escapes and concatenation before the code containing the snippet will compile. Text blocks do not support raw strings, that is, strings whose characters are not processed in any way. Interpolation may be considered in a future JEP. Text blocks do not directly support string interpolation. It is not a goal to define new operators, distinct from +, that take String operands.
It is not a goal to define a new reference type, distinct from, for the strings expressed by any new construct. Support migration from string literals by stipulating that any new construct can express the same set of strings as a string literal, interpret the same escape sequences, and be manipulated in the same ways as a string literal.Īdd escape sequences for managing explicit white space and newline control. Simplify the task of writing Java programs by making it easy to express strings that span several lines of source code, while avoiding escape sequences in common cases.Įnhance the readability of strings in Java programs that denote code written in non-Java languages. Feedback on JDK 13 suggested that text blocks should be previewed again in JDK 14, with the addition of two new escape sequences. JEP 355 was targeted to JDK 13 in mid 2019 as a preview feature. Text blocks were proposed by JEP 355 in early 2019 as a follow-on to explorations begun in JEP 326 (Raw String Literals), which was withdrawn and did not appear in JDK 12. This is a preview language feature in JDK 14. A text block is a multi-line string literal that avoids the need for most escape sequences, automatically formats the string in a predictable way, and gives the developer control over the format when desired.
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