From 0c318edc8997dafcf22ca1613c32981dfb6446f7 Mon Sep 17 00:00:00 2001
From: Peter Reilly <peterreilly@apache.org>
Date: Wed, 20 Sep 2006 22:32:24 +0000
Subject: [PATCH] Performace:   cache last FileUtils.fromUri() result

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@448377 13f79535-47bb-0310-9956-ffa450edef68
---
 .../org/apache/tools/ant/util/FileUtils.java  | 23 +++++++++++++++++--
 1 file changed, 21 insertions(+), 2 deletions(-)

diff --git a/src/main/org/apache/tools/ant/util/FileUtils.java b/src/main/org/apache/tools/ant/util/FileUtils.java
index 0a77df240..a94394881 100644
--- a/src/main/org/apache/tools/ant/util/FileUtils.java
+++ b/src/main/org/apache/tools/ant/util/FileUtils.java
@@ -86,6 +86,16 @@ public class FileUtils {
     public static final long NTFS_FILE_TIMESTAMP_GRANULARITY = 1;
 
 
+    /**
+     * A one item cache for fromUri.
+     * fromUri is called for each element when parseing ant build
+     * files. It is a costly operation. This just caches the result
+     * of the last call.
+     */
+    private Object cacheFromUriLock = new Object();
+    private String cacheFromUriRequest = null;
+    private String cacheFromUriResponse = null;
+
     /**
      * Factory method.
      *
@@ -1137,8 +1147,17 @@ public class FileUtils {
      * @since Ant 1.6
      */
     public String fromURI(String uri) {
-        String path = Locator.fromURI(uri);
-        return isAbsolutePath(path) ? normalize(path).getAbsolutePath() : path;
+        synchronized (cacheFromUriLock) {
+            if (uri.equals(cacheFromUriRequest)) {
+                return cacheFromUriResponse;
+            }
+            String path = Locator.fromURI(uri);
+            String ret = isAbsolutePath(path)
+                ? normalize(path).getAbsolutePath() : path;
+            cacheFromUriRequest = uri;
+            cacheFromUriResponse = ret;
+            return ret;
+        }
     }
 
     /**