Summary

Introduced new API java.lang.management.RuntimeMXBean.getPid to get process ID of running Java virtual machine.

Problem

The platform MBean does not provide any API to get the process ID of a running JVM. Some JMX tools rely on the hotspot implementation of RuntimeMXBean::getName which returns < pid >@< hostname >.

Solution

Introduced new API java.lang.management.RuntimeMXBean.getPid, so that JMX tools can directly get process ID instead of relying on the implementation detail, RuntimeMXBean#getName().split("@")[0].

Specification

  --- old/src/java.management/share/classes/java/lang/management/RuntimeMXBean.java 2017-11-02 15:03:57.177210581 +0530
+++ new/src/java.management/share/classes/java/lang/management/RuntimeMXBean.java   2017-11-02 15:03:56.993210581 +0530
@@ -25,6 +25,9 @@

 package java.lang.management;

+import java.security.AccessController;
+import java.security.PrivilegedAction;
+
 /**
  * The management interface for the runtime system of
  * the Java virtual machine.
@@ -61,6 +64,22 @@
  */
 public interface RuntimeMXBean extends PlatformManagedObject {
     /**
+     * Returns the {@linkplain ProcessHandle#pid process ID} representing
+     * the running Java virtual machine.
+     *
+     * @implSpec The default implementation returns {@link ProcessHandle#pid process ID}
+     * of the {@linkplain ProcessHandle#current current process}.
+     *
+     * @return the process ID representing the running Java virtual machine.
+     *
+     * @since 10
+     */
+    public default long getPid() {
+        return AccessController.doPrivileged((PrivilegedAction<Long>)
+                () -> ProcessHandle.current().pid());
+    }
+
+    /**
      * Returns the name representing the running Java virtual machine.
      * The returned name string can be any arbitrary string and
      * a Java virtual machine implementation can choose