src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/tools/JSnap.java

*** 23,37 ****
--- 23,41 ----
   */
  
  package sun.jvm.hotspot.tools;
  
  import java.io.*;
+ import java.util.*;
+ import java.util.stream.*;
  import sun.jvm.hotspot.debugger.JVMDebugger;
  import sun.jvm.hotspot.runtime.*;
  
  public class JSnap extends Tool {
  
+     private boolean all;
+ 
      public JSnap() {
          super();
      }
  
      public JSnap(JVMDebugger d) {
*** 43,53 ****
          if (PerfMemory.initialized()) {
              PerfDataPrologue prologue = PerfMemory.prologue();
              if (prologue.accessible()) {
                  PerfMemory.iterate(new PerfMemory.PerfDataEntryVisitor() {
                          public boolean visit(PerfDataEntry pde) {
!                             if (pde.supported()) {
                                  out.print(pde.name());
                                  out.print('=');
                                  out.println(pde.valueAsString());
                              }
                              // goto next entry
--- 47,57 ----
          if (PerfMemory.initialized()) {
              PerfDataPrologue prologue = PerfMemory.prologue();
              if (prologue.accessible()) {
                  PerfMemory.iterate(new PerfMemory.PerfDataEntryVisitor() {
                          public boolean visit(PerfDataEntry pde) {
!                             if (all || pde.supported()) {
                                  out.print(pde.name());
                                  out.print('=');
                                  out.println(pde.valueAsString());
                              }
                              // goto next entry
*** 60,69 ****
--- 64,89 ----
          } else {
              out.println("PerfMemory is not initialized");
          }
      }
  
+     @Override
+     protected void printFlagsUsage() {
+         System.out.println("    -a\tto print all performance counters");
+         super.printFlagsUsage();
+     }
+ 
      public static void main(String[] args) {
          JSnap js = new JSnap();
+         js.all = Arrays.stream(args)
+                        .anyMatch(s -> s.equals("-a"));
+ 
+         if (js.all) {
+             args = Arrays.stream(args)
+                          .filter(s -> !s.equals("-a"))
+                          .collect(Collectors.toList())
+                          .toArray(new String[0]);
+         }
+ 
          js.execute(args);
      }
  }