问题
I may do some cross-compilations for legacy projects and I noticed with recent JDKs that we are limited to some specific versions for the source, target and release JVM arguments.
How to get the supported versions for these arguments ?
回答1:
Indeed the supported values depend on the major JDK version used.
You can find the information on the javac documentation of the respective major JDK versions (the links are referenced below).
Some general notes about these arguments :
The
sourceand thetargetversion in the Maven configuration should not be superior to the JDK version used.
A older version of the JDK cannot compile with a more recent version since it doesn't know its specification.The
releaseargument exists from Java 9.As the
sourceand thetargetare the same, thereleaseargument should be favored oversourceandtarget. It is shorter to specify and it ensures a better cross compilation compatibility and whatever even if you don't do cross compilations, it will not hurt.
For more explanations please refer to this excellent answer.
source/target/release supported versions :
For Java 7
- supported
source:
1.3, 1.4, 1.5 (also 5), 1.6 (also 6), and 1.7 (also 7).
- supported
target:
1.1, 1.2, 1.3, 1.4, 1.5 (also 5), 1.6 (also 6), and 1.7 (also 7).
For Java 8
- supported
source:
1.3, 1.4, 1.5 (also 5), 1.6 (also 6), 1.7 (also 7), and 1.8 (also 8).
- supported
target:
1.1, 1.2, 1.3, 1.4, 1.5 (also 5), 1.6 (also 6), 1.7 (also 7), and 1.8 (also 8).
For Java 9
- supported
source:
1.6 (also 6), 1.7 (also 7), 1.8 (also 8), and 9.
- supported
target:
1.6 (also 6), 1.7 (also 7), 1.8 (also 8) and 9.
- supported
release:
6, 7, 8, and 9.
For Java 10
- supported
source:
1.6 (also 6), 1.7 (also 7), 1.8 (also 8), 9, and 10.
- supported
target:
1.6 (also 6), 1.7 (also 7), 1.8 (also 8), 9 and 10.
- supported
release:
6, 7, 8, 9, and 10.
You could have more details in the javac documentation for JDK 1.8, JDK 9 and JDK 10
来源：https://stackoverflow.com/questions/51692748/java-compilation-source-target-and-release-supported-versions