Re: [libvirt] [PATCH libvirt-java] Require at least Java 8
At Wed, 2 Sep 2015 17:38:03 +0200,
Wido den Hollander wrote:
> The current code doesn't compile under Java 7, but Java 7 is also EOL.
>
>
> That should not be the case. Can you provide the error messages or
> simply point to the place where Java 8 classes are used?
>
build:
[javac] Compiling 98 source files to
/home/wido/repos/libvirt-java/target/classes
[javac] warning: [options] bootstrap class path not set in
conjunction with -source 1.7
[javac]
/home/wido/repos/libvirt-java/src/main/java/org/libvirt/event/DomainEvent.java:63:
error: incompatible types: inference variable T#1 has incompatible upper
bounds Enum<T#2>,T#3
[javac] return this.type.obtain(this.detail);
[javac] ^
[javac] where T#1,T#2,T#3 are type-variables:
[javac] T#1 extends Enum<T#1> declared in method <T#1>obtain(int)
[javac] T#2 extends T#3
[javac] T#3 extends Enum<T#3>,DomainEventDetail declared in
method <T#3>getDetail()
[javac] 1 error
[javac] 1 warning
This reminded me of a problem I once saw with the Java 7 (I think)
compiler being unable to correctly infer the types when calling static
generic methods.
Since I always used the Java 7 compiler to compile the code and as I
saw the javac warning above, I got curious.
The thing is: the code compiles just fine with an actual Java 7
compiler (OpenJDK 1.7.0_85), but not when using a Java 8 compiler
(OpenJDK 1.8.0_60) with the `-source 1.7` switch.
But if the compile issue can be fixed we can probably require at
least
Java 7. I think Java 6 is dangerous.
I'm still thinking about this. Maybe you're right. But still, the code
is valid 1.7 source code. Should we prevent that code from compiling
on Java 7 to protect users from using an obsolete JVM? I don't think
this is the right place to control that.
--
Claudio
--