RFR: 8313174: Create fewer predictable port clashes in management tests

[Chris Plummer]

On Wed, 26 Jul 2023 10:50:09 GMT, Kevin Walls <kevinw at openjdk.org> wrote:

> Specifically noticed on linux-aarch64, detection of port clashes by LocateRegistry.createRegistry(port) appears "racy".
> 
> Predictable port clashes can be avoided, tests that are likely to run at the same time should not choose the same port.
> 
> Why now?  The RMI related parts are obviously fairly stable these days, as are the tests themselves.
> Our OS version/host mix for testing may have changed.  The problems I looked into were on ol8-aarch64.
> 
> It doesn't seem necessary to add complexities to the tests, or change LocateRegistry much at this point, when a simple change to the tests can avoid asking for so many port clashes.
> 
> 
> 
> test/jdk/javax/management/remote/mandatory/passwordAuthenticator/RMIPasswdAuthTest.java:            int port = 5800;  	// 5801 to 5820
> test/jdk/javax/management/remote/mandatory/passwordAuthenticator/RMIAltAuthTest.java:            int port = 5800;	// 5821 to 5840
> test/jdk/javax/management/remote/mandatory/socketFactories/RMISocketFactoriesTest.java:            int port = 5800;	// 5841 to 5860
> test/jdk/javax/management/remote/mandatory/subjectDelegation/SubjectDelegation1Test.java:            int port = 5800;	// 5861 to 5880
> test/jdk/javax/management/remote/mandatory/subjectDelegation/SubjectDelegation2Test.java:            int port = 5800;	// 5881 to 5900
> test/jdk/javax/management/remote/mandatory/subjectDelegation/SubjectDelegation3Test.java:            int port = 5800;	// 5901 to 5920

Changes requested by cjplummer (Reviewer).

test/jdk/javax/management/remote/mandatory/subjectDelegation/SubjectDelegation2Test.java line 76:

> 74:             Registry reg = null;
> 75:             int port = 5880;
> 76:             while (port++ < 6000) {

Does the loop need to terminate on 5900 instead of 6000?

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

PR Review: https://git.openjdk.org/jdk/pull/15039#pullrequestreview-1548296441
PR Review Comment: https://git.openjdk.org/jdk/pull/15039#discussion_r1275303419