RFR: 8260378: [TESTBUG] DcmdMBeanTestCheckJni.java reports false positive

[Severin Gehwolf]

On Tue, 26 Jan 2021 11:33:37 GMT, Severin Gehwolf <sgehwolf at openjdk.org> wrote:

> I propose to add additional context to the string which must not match after [JDK-8258836](https://bugs.openjdk.java.net/browse/JDK-8258836). This then passes the test for a fixed JDK (including JDKs with JDK-8187450 *not* fixed).
> 
> Testing:
> - [x] Reverted the fix from product code of JDK-8258836, ran the test. Failed as expected.
> - [x] Ran the updated test on current head. Passed.
> - [x] Ran the updated test with [1] included. Passed even though the processes' stdout contained [2].
> 
> [1] Explicitly add a call to NetworkInterface.getNetworkInterfaces()
> diff --git a/test/jdk/com/sun/management/DiagnosticCommandMBean/DcmdMBeanTestCheckJni.java b/test/jdk/com/sun/management/DiagnosticCommandMBean/DcmdMBeanTestCheckJni.java
> index 73e53da63f1..4f32af3f463 100644
> --- a/test/jdk/com/sun/management/DiagnosticCommandMBean/DcmdMBeanTestCheckJni.java
> +++ b/test/jdk/com/sun/management/DiagnosticCommandMBean/DcmdMBeanTestCheckJni.java
> @@ -62,6 +62,7 @@ class DcmdMBeanRunner {
>          "com.sun.management:type=DiagnosticCommand";
>  
>      public static void main(String[] args) throws Exception {
> +        java.net.NetworkInterface.getNetworkInterfaces();
>          MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
>          JMXServiceURL url = new JMXServiceURL("rmi", null, 0);
>          JMXConnectorServer cs = null;
> [2]
> --- ProcessLog ---
> cmd: /disk/openjdk/upstream-sources/git/jdk-jdk/./build/linux-x86_64-server-release/images/jdk/bin/java -cp /disk/openjdk/upstream-sources/git/jdk-jdk/JTwork/classes/com/sun/management/DiagnosticCommandMBean/DcmdMBeanTestCheckJni.d:/disk/openjdk/upstream-sources/git/jdk-jdk/test/jdk/com/sun/management/DiagnosticCommandMBean:/disk/openjdk/upstream-sources/git/jdk-jdk/JTwork/classes/test/lib:/disk/openjdk/upstream-sources/git/jdk-jdk/test/lib:/disk/openjdk/upstream-sources/jtreg-5.1-b01/lib/javatest.jar:/disk/openjdk/upstream-sources/jtreg-5.1-b01/lib/jtreg.jar -Xcheck:jni DcmdMBeanRunner
> exitvalue: 0
> stderr:
> stdout: WARNING: JNI local refs: 33, exceeds capacity: 32
>         at java.net.NetworkInterface.getAll(java.base at 17-internal/Native Method)
>         at java.net.NetworkInterface.getNetworkInterfaces(java.base at 17-internal/NetworkInterface.java:351)
>         at DcmdMBeanRunner.main(DcmdMBeanTestCheckJni.java:65)
> DiagnosticCommand MBean: com.sun.management:type=DiagnosticCommand
> DcmdMBeanRunner COMPLETE

@dcubed-ojdk Please review! Thanks.

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

PR: https://git.openjdk.java.net/jdk/pull/2234