On Wed, 30 Jul 2025 11:19:33 GMT, Kevin Walls <kev...@openjdk.org> wrote:
> A long-standing omission where MBeanServer.registerMBean documents exception > behaviour, but we actually throw an NPE. We should recognise a null object > and return the wrapped exception we document. > > This wrapping behaviour is common elsewhere in this area, e.g. > unregisterMBean which checks for a null name and throws > RuntimeOperationsException. > > Docs: > https://docs.oracle.com/en/java/javase/24/docs/api/java.management/javax/management/MBeanServer.html#registerMBean(java.lang.Object,javax.management.ObjectName) > > Throws: > RuntimeOperationsException - Wraps a java.lang.IllegalArgumentException: The > object passed in parameter is null or no object name is specified. > > > Current behaviour: > > > $ java MBS_NPE.java > Exception in thread "main" java.lang.NullPointerException: Cannot invoke > "Object.getClass()" because "object" is null > at > java.management/com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerMBean(DefaultMBeanServerInterceptor.java:296) > at > java.management/com.sun.jmx.mbeanserver.JmxMBeanServer.registerMBean(JmxMBeanServer.java:511) > at MBS_NPE.main(MBS_NPE.java:11) > > > Should be changed to: > > > $ java MBS_NPE.java > javax.management.RuntimeOperationsException: Exception occurred trying to > register the MBean > at > java.management/com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerMBean(DefaultMBeanServerInterceptor.java:297) > at > java.management/com.sun.jmx.mbeanserver.JmxMBeanServer.registerMBean(JmxMBeanServer.java:511) > at MBS_NPE.main(MBS_NPE.java:11) > at > java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104) > at java.base/java.lang.reflect.Method.invoke(Method.java:565) > at > jdk.compiler/com.sun.tools.javac.launcher.SourceLauncher.execute(SourceLauncher.java:258) > at > jdk.compiler/com.sun.tools.javac.launcher.SourceLauncher.run(SourceLauncher.java:138) > at > jdk.compiler/com.sun.tools.javac.launcher.SourceLauncher.main(SourceLauncher.java:76) > Caused by: java.lang.IllegalArgumentException: Object cannot be null > at > java.management/com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerMBean(DefaultMBeanServerInterceptor.java:295) > ... 7 more I assume a CSR should be created to track the behavior. I don't expect there is code catching IAE instead of RuntimeOperationsException for this scenario but it's possible. Are you planning to add a test? ------------- PR Comment: https://git.openjdk.org/jdk/pull/26548#issuecomment-3135955498
