From 3bdf9aad6735cfc471ccce91e7136da2efa7ad24 Mon Sep 17 00:00:00 2001
From: Eugene Zhuravlev <jeka@intellij.com>
Date: Tue, 25 Jun 2013 09:53:10 +0400
Subject: [PATCH] reduce thread blocking time

---
 .../jetbrains/jps/incremental/FSCache.java    | 21 ++++++++-----------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/jps/jps-builders/src/org/jetbrains/jps/incremental/FSCache.java b/jps/jps-builders/src/org/jetbrains/jps/incremental/FSCache.java
index 75b5a9910f7a..689d2fea362a 100644
--- a/jps/jps-builders/src/org/jetbrains/jps/incremental/FSCache.java
+++ b/jps/jps-builders/src/org/jetbrains/jps/incremental/FSCache.java
@@ -19,6 +19,7 @@ import gnu.trove.THashMap;
 import org.jetbrains.annotations.Nullable;
 
 import java.io.File;
+import java.util.Collections;
 import java.util.Map;
 
 /**
@@ -37,24 +38,20 @@ public class FSCache {
 
   private static final File[] NULL_VALUE = new File[0];
   private static final File[] EMPTY_FILE_ARRAY = new File[0];
-  private final Map<File, File[]> myMap = new THashMap<File, File[]>();
+  private final Map<File, File[]> myMap = Collections.synchronizedMap(new THashMap<File, File[]>());
 
   @Nullable
   public File[] getChildren(File file) {
-    synchronized (myMap) {
-      final File[] children = myMap.get(file);
-      if (children != null) {
-        return children == NULL_VALUE? null : children;
-      }
-      final File[] files = file.listFiles();
-      myMap.put(file, files == null? NULL_VALUE : (files.length == 0? EMPTY_FILE_ARRAY : files));
-      return files;
+    final File[] children = myMap.get(file);
+    if (children != null) {
+      return children == NULL_VALUE? null : children;
     }
+    final File[] files = file.listFiles();
+    myMap.put(file, files == null? NULL_VALUE : (files.length == 0? EMPTY_FILE_ARRAY : files));
+    return files;
   }
 
   public void clear() {
-    synchronized (myMap) {
-      myMap.clear();
-    }
+    myMap.clear();
   }
 }