RFR: 8264258: Unknown lookups in the java package give misleading compilation errors

[Jesper Steen Møller]

On Sun, 11 Apr 2021 12:49:35 GMT, Jesper Steen Møller <jespersm at openjdk.org> wrote:

> Unknown lookups in the java package give misleading compilation errors

The problem only really occurs for the 'java' package, which is special according to the JLS, since it is always in scope (as per §6.3) and observable (as per §7.4.3). The special handling of unfound symbols in com.sun.tools.javac.comp.Resolve.SymbolNotFoundError.getDiagnostic explcitly handles the issues of unfound classes in unfound packages, and fails to differentiate 'java'. 

My research shows that the error was introduced with Jigsaw, see commit 001ebb3a7279d9a193acebc389cbbee867fa5eb3 where the blessed output for TryWithResources/TwrForVariable3.out was changed from "unknown class lang" to "unknown packages java".

-------------

PR: https://git.openjdk.java.net/jdk/pull/3428