src/jdk.compiler/share/classes/com/sun/tools/javac/api/JavacTaskPool.java

rev 50902 : imported patch 8206122-Use-Queue-in-place-of-ArrayList-when-need-to-remove-first-element

*** 1,7 ****
  /*
!  * Copyright (c) 2015, 2017, 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) 2015, 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
*** 25,37 ****
  
  package com.sun.tools.javac.api;
  
  import java.io.PrintStream;
  import java.io.Writer;
  import java.util.ArrayList;
  import java.util.Collection;
! import java.util.Collections;
  import java.util.HashMap;
  
  import com.sun.source.tree.ClassTree;
  import com.sun.source.tree.CompilationUnitTree;
  import com.sun.source.util.JavacTask;
--- 25,38 ----
  
  package com.sun.tools.javac.api;
  
  import java.io.PrintStream;
  import java.io.Writer;
+ import java.util.ArrayDeque;
  import java.util.ArrayList;
  import java.util.Collection;
! import java.util.Deque;
  import java.util.HashMap;
  
  import com.sun.source.tree.ClassTree;
  import com.sun.source.tree.CompilationUnitTree;
  import com.sun.source.util.JavacTask;
*** 99,111 ****
   * deletion without notice.</b>
   */
  public class JavacTaskPool {
  
      private static final JavacTool systemProvider = JavacTool.create();
  
      private final int maxPoolSize;
!     private final Map<List<String>, List<ReusableContext>> options2Contexts = new HashMap<>();
      private int id;
  
      private int statReused = 0;
      private int statNew = 0;
      private int statPolluted = 0;
--- 100,113 ----
   * deletion without notice.</b>
   */
  public class JavacTaskPool {
  
      private static final JavacTool systemProvider = JavacTool.create();
+     private static final Deque<ReusableContext> EMPTY_DEQUE = new ArrayDeque<>(0);
  
      private final int maxPoolSize;
!     private final Map<List<String>, Deque<ReusableContext>> options2Contexts = new HashMap<>();
      private int id;
  
      private int statReused = 0;
      private int statNew = 0;
      private int statPolluted = 0;
*** 157,174 ****
                               .collect(Collectors.toCollection(ArrayList::new));
  
          ReusableContext ctx;
  
          synchronized (this) {
!             List<ReusableContext> cached =
!                     options2Contexts.getOrDefault(opts, Collections.emptyList());
  
              if (cached.isEmpty()) {
                  ctx = new ReusableContext(opts);
                  statNew++;
              } else {
!                 ctx = cached.remove(0);
                  statReused++;
              }
          }
  
          ctx.useCount++;
--- 159,176 ----
                               .collect(Collectors.toCollection(ArrayList::new));
  
          ReusableContext ctx;
  
          synchronized (this) {
!             Deque<ReusableContext> cached =
!                     options2Contexts.getOrDefault(opts, EMPTY_DEQUE);
  
              if (cached.isEmpty()) {
                  ctx = new ReusableContext(opts);
                  statNew++;
              } else {
!                 ctx = cached.remove();
                  statReused++;
              }
          }
  
          ctx.useCount++;
*** 198,208 ****
                                              .findFirst()
                                              .get();
                      options2Contexts.get(toRemove.arguments).remove(toRemove);
                      statRemoved++;
                  }
!                 options2Contexts.computeIfAbsent(ctx.arguments, x -> new ArrayList<>()).add(ctx);
                  ctx.timeStamp = id++;
              }
          }
  
          return result;
--- 200,210 ----
                                              .findFirst()
                                              .get();
                      options2Contexts.get(toRemove.arguments).remove(toRemove);
                      statRemoved++;
                  }
!                 options2Contexts.computeIfAbsent(ctx.arguments, x -> new ArrayDeque<>()).add(ctx);
                  ctx.timeStamp = id++;
              }
          }
  
          return result;