jmx-dev RFR(S): 8234484: Add ability to configure third port for remote JMX

[Yangfei (Felix)]

Hi Daniel,

    Thanks for the suggestions.  
    I modified the patch making the third port also configurable via the management.properties file.  
    New webrev: http://cr.openjdk.java.net/~fyang/8234484/webrev.01/  

    Previously, we test the effectiveness of the patch by checking the port usage with -Dsun.rmi.transport.tcp.logLevel=VERBOSE.  
    Is it good to modify the following test case specifying the third port for the testing purpose?  

diff -r d630c0a63222 test/jdk/sun/management/jmxremote/bootstrap/JMXInterfaceBindingTest.java
--- a/test/jdk/sun/management/jmxremote/bootstrap/JMXInterfaceBindingTest.java	Wed Jan 08 08:53:28 2020 +0900
+++ b/test/jdk/sun/management/jmxremote/bootstrap/JMXInterfaceBindingTest.java	Sat Jan 11 15:30:25 2020 +0000
@@ -31,6 +31,7 @@
 
 import jdk.test.lib.process.OutputAnalyzer;
 import jdk.test.lib.process.ProcessTools;
+import jdk.test.lib.Utils;
 
 /**
  * @test
@@ -203,6 +204,12 @@
             args.add("-Dcom.sun.management.jmxremote.host=" + address);
             args.add("-Dcom.sun.management.jmxremote.port=" + jmxPort);
             args.add("-Dcom.sun.management.jmxremote.rmi.port=" + rmiPort);
+            try {
+                int port = Utils.getFreePort();
+                args.add("-Dcom.sun.management.jmxlocal.port=" + port);
+            } catch (Exception e) {
+                System.out.println(e);
+            }
             args.add("-Dcom.sun.management.jmxremote.authenticate=false");
             args.add("-Dcom.sun.management.jmxremote.ssl=" + Boolean.toString(useSSL));
             // This is needed for testing on loopback

Felix

> 
> Hi Felix,
> 
> Shouldn't this be configurable via the management.properties file, like all other
> JMX properties?
> 
> Also on the one hand - it would be good to have a test.
> On the other hand - writing a stable test will be problematic as there is no way
> to ensure that any particular port number will be available for the agent to bind
> to.
> 
> best regards,
> 
> -- daniel
> 
> On 08/01/2020 01:09, Yangfei (Felix) wrote:
> > Hi,
> >
> > Please review this patch adding a way to configure the third port for
> > remote JMX.
> >
> > Currently, it is possible to configure two of the three ports for JMX
> > with com.sun.management.jmxremote.port and
> > com.sun.management.jmxremote.rmi.port.
> >
> > However, there is no way to configure the third port. This can cause
> > problems if the randomly assigned port conflicts with another service
> > that has not yet acquired its port.
> >
> >     Bug: https://bugs.openjdk.java.net/browse/JDK-8234484
> >
> >    Webrev: http://cr.openjdk.java.net/~fyang/8234484/webrev.00/
> >
> >    Passed tiered-1 test.
> >
> > Thanks,
> >
> > Felix
> >