RFR(s): 8153330: deprecate Runtime.traceInstructions & traceMethodCalls for removal

[Stuart Marks]

Hi all,

I missed a couple bits of cruft in the previous round of java.lang deprecations: 
the Runtime.traceInstructions() and traceMethodCalls() methods.

Their implementations are empty. That is, they do absolutely nothing.

They're only mentioned a couple times in the JDK, in CORBA (!) and in some RMI 
tests (!), and in a few symbol files. On grepcode.com, there are a couple uses, 
mainly attempting to enable these in response to some debugging flag being given.

Thus, I propose these be deprecated for removal. Please review diff below.

Thanks,

s'marks



diff -r 92280897299f src/java.base/share/classes/java/lang/Runtime.java
--- a/src/java.base/share/classes/java/lang/Runtime.java	Mon Apr 18 14:10:14 
2016 -0700
+++ b/src/java.base/share/classes/java/lang/Runtime.java	Tue Apr 19 15:04:25 
2016 -0700
@@ -718,41 +718,27 @@
      }

      /**
-     * Enables/Disables tracing of instructions.
-     * If the {@code boolean} argument is {@code true}, this
-     * method suggests that the Java virtual machine emit debugging
-     * information for each instruction in the virtual machine as it
-     * is executed. The format of this information, and the file or other
-     * output stream to which it is emitted, depends on the host environment.
-     * The virtual machine may ignore this request if it does not support
-     * this feature. The destination of the trace output is system
-     * dependent.
-     * <p>
-     * If the {@code boolean} argument is {@code false}, this
-     * method causes the virtual machine to stop performing the
-     * detailed instruction trace it is performing.
-     *
-     * @param   on   {@code true} to enable instruction tracing;
-     *               {@code false} to disable this feature.
+     * Not implemented.
+     *
+     * @deprecated
+     * This method was intended to control instruction tracing.
+     * It has been superseded by JVM-specific tracing mechanisms.
+     *
+     * @param on ignored
       */
+    @Deprecated(since="9", forRemoval=true)
      public void traceInstructions(boolean on) { }

      /**
-     * Enables/Disables tracing of method calls.
-     * If the {@code boolean} argument is {@code true}, this
-     * method suggests that the Java virtual machine emit debugging
-     * information for each method in the virtual machine as it is
-     * called. The format of this information, and the file or other output
-     * stream to which it is emitted, depends on the host environment. The
-     * virtual machine may ignore this request if it does not support
-     * this feature.
-     * <p>
-     * Calling this method with argument false suggests that the
-     * virtual machine cease emitting per-call debugging information.
-     *
-     * @param   on   {@code true} to enable instruction tracing;
-     *               {@code false} to disable this feature.
+     * Not implemented.
+     *
+     * @deprecated
+     * This method was intended to control method call tracing.
+     * It has been superseded by JVM-specific tracing mechanisms.
+     *
+     * @param on ignored
       */
+    @Deprecated(since="9", forRemoval=true)
      public void traceMethodCalls(boolean on) { }

      /**