Thanks Zhong, you are correct. So we additionally can save again 1 variable and 2 lines.
-Ulf Am 09.10.2012 23:08, schrieb Zhong Yu:
Ulf, since allUpper <==> ca==null we don't need allUpper... On Tue, Oct 9, 2012 at 2:31 PM, Ulf Zibis <ulf.zi...@cosoco.de> wrote:Hi, I did not look into the details, but the hint about performance on String.toLower in WindowsNTFileSystem catched my attention. Here is a very fast converter, which may be enough for calculating the hash: // Private ASCII-only optimized version public static final String toUpper(final String s) { boolean allUpper = true; char[] ca = null; for (int i=0; i<s.length(); i++) { int c = s.charAt(i); if (c >= 'a' && c <= 'z') { if (allUpper) { ca = s.toCharArray(); allUpper = false; } ca[i] -= '\u0020'; } } return allUpper ? s : new String(ca); } It also avoids instantiation of new objects, if there is nothing to change. Note: the equivalent toLower algorithm statistically would be little slower on latin characters, but maybe faster on wide spreaded Unicode characters. -Ulf Am 09.10.2012 19:46, schrieb Dan Xu:Hi folks, Please help review the code change for CR7186817 to remove Windows 95/98/ME support. The webrev has been uploaded to http://cr.openjdk.java.net/~dxu/7186817/webrev/ <http://cr.openjdk.java.net/%7Edxu/7186817/webrev/> The main focus of this clean-up is in IO area. And I also cleaned java/lang/ProcessImpl_md.c and java/util/TimeZone_md.c in this transaction. Thanks, -Dan
