tree 121152eabaf1097dc6685fa50610ee113c3c0b96
parent 21738f6032b5d2a3749aca76d7f8371b0acd57d6
author Pete Gillin <peteg@google.com> 1562933777 +0100
committer Pete Gillin <peteg@google.com> 1567091404 +0100

Normalize and validate the java_version property.

There are two parts to this change.

Normalization: If a module specifies 'java_version: "9"', this is now
normalized into 'java_version: "1.9"'. Users might reasonably assume
that "9" should be valid, since javac treats them as synonyms (and, in
fact, the javac documentation lists "9" as a valid value but doesn't
mention "1.9"). However, the soong code that triggers JPMS support
(i.e. setting -system rather than --boot-class-path) looks for the
string "1.9", so prior to this change modules specifying "9" would
fail with a confusing error ('javac: option --boot-class-path not
allowed with target 1.9'). Normalizing "9" to "1.9" fixes this. (The
change normalizes the other supported values, too, for consistency.)

Validation: This change also makes the build fail-fast with a clear
error message for invalid values. In particular, modules specifying
"10" or "11" fail with an explicit message that this is not supported,
in anticipation of the switch to OpenJDK 11. Prior to this change,
modules setting those values would get the confusing
'--boot-class-path not allowed' error described about since JPMS
support would not be triggered. (That could be fixed by changing the
JPMS logic to trigger on "10" and "11", but that would be dangerous
since support in the rest of the system for v54 and v55 class files is
unproven: it is better to fail explicitly.) (This change also makes it
fail-fast for any unrecognized values.)

Test: make java
Test: make targets with java_version set to "1.8", "8", "1.9", and "9", all succeed ("9" fails without this change)
Test: make targets with java_version set to "10" and "11", fail with the explicit "not supported" message
Test: make target with java_version set to "xxx", fails fast with the "unrecognized" message
Bug: 131683177
Change-Id: I2f5eb496c29d7736c68c01401c3f0967aeae99fc