I'm not sure Sun/Oracle ever formally specified this behavior, but as a JVM engineer since Java 0.98 I can attest to it. This behavior is also described in JEP-280: "Currently javac translates String concatenation into StringBuilder::append chains" (referring to Java 8).
The advantages of using StringBuilder explicitly, that I can think of, are: * No risk of accidentally constructing multiple StringBuilders, e.g. (strA + strB) + (strC + strD) * Ability to explicitly set the right capacity, e.g. new StringBuilder(new size) Peter On Sun, Dec 15, 2024, 11:03 AM Elliotte Rusty Harold <[email protected]> wrote: > On Sun, Dec 15, 2024 at 2:00 PM Peter Burka <[email protected]> wrote: > > > > Before Java 9, javac always generated StringBuilder calls for string > > concatenation (or StringBuffer prior to Java 2). Using + is less verbose, > > generates the same code, is more readable, and, when we do finally bump > the > > compile target, will generate better code. > > > > reference? > > > -- > Elliotte Rusty Harold > [email protected] > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > >
