src/jdk.jcmd/share/classes/sun/tools/jstat/Expression.java

*** 1,7 ****
  /*
!  * Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
--- 1,7 ----
  /*
!  * Copyright (c) 2004, 2018, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
*** 38,47 ****
--- 38,48 ----
      private boolean debug = Boolean.getBoolean("Expression.debug");
      private Expression left;
      private Expression right;
      private Operator operator;
      private int ordinal = nextOrdinal++;
+     private boolean required = false;
  
      Expression() {
          if (debug) {
              System.out.println("Expression " + ordinal + " created");
          }
*** 50,59 ****
--- 51,61 ----
      void setLeft(Expression left) {
          if (debug) {
              System.out.println("Setting left on " + ordinal + " to " + left);
          }
          this.left = left;
+         this.left.setRequired(required);
      }
  
      Expression getLeft() {
          return left;
      }
*** 61,70 ****
--- 63,73 ----
      void setRight(Expression right) {
          if (debug) {
              System.out.println("Setting right on " + ordinal + " to " + right);
          }
          this.right = right;
+         this.right.setRequired(required);
      }
  
      Expression getRight() {
          return right;
      }
*** 78,87 ****
--- 81,104 ----
  
      Operator getOperator() {
          return operator;
      }
  
+     void setRequired(boolean r) {
+         this.required = r;
+         if (left != null) {
+             left.setRequired(required);
+         }
+         if (right != null) {
+             right.setRequired(required);
+         }
+     }
+ 
+     boolean isRequired() {
+         return required;
+     }
+ 
      public String toString() {
          StringBuilder b = new StringBuilder();
          b.append('(');
          if (left != null) {
              b.append(left.toString());