UNC pathnames did not work for ANT_HOME or -lib locations on Windows.

PR: 27922


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@276275 13f79535-47bb-0310-9956-ffa450edef68

WHATSNEW

@@ -26,6 +26,9 @@ Fixed bugs:
 * I/O-intensive processes hung when executed via <exec spawn="true">.
   Bugzilla reports 23893/26852.
 
+* UNC pathnames did not work for ANT_HOME or -lib locations on Windows.
+  Bugzilla report 27922.
+
 
 Other changes:
 --------------

src/main/org/apache/tools/ant/launch/Locator.java

@@ -101,13 +101,18 @@ public final class Locator {
      * @since Ant 1.6
      */
     public static String fromURI(String uri) {
-        if (!uri.startsWith("file:")) {
-            throw new IllegalArgumentException("Can only handle file: URIs");
-        }
-        if (uri.startsWith("file://")) {
-            uri = uri.substring(7);
-        } else {
-            uri = uri.substring(5);
+        try {
+            URL url = new URL(uri);
+            if (!("file".equals(url.getProtocol()))) {
+                throw new IllegalArgumentException("Can only handle file: URIs");
+            }
+            StringBuffer buf = new StringBuffer(url.getHost());
+            if (buf.length() > 0) {
+                buf.insert(0, "//");
+            }
+            buf.append(url.getPath());
+            uri = buf.toString();
+        } catch (MalformedURLException emYouEarlEx) {
         }
 
         uri = uri.replace('/', File.separatorChar);