Changeset 6175 in josm for trunk/src/org/openstreetmap/josm/tools

Timestamp:

2013-08-22T14:41:30+02:00 (13 years ago)

Author:

Don-vip

Message:

see #8902 - Small performance enhancements / coding style (patches by shinigami):

• bytestohexstring.diff: byte[] to hex string change + small test
• collfix.diff : problem in generic collection definition
• styleiteration.diff: useless iteration to do end of list
• environment.diff: Environment - merge chained ops (each created copy of env.) to one

File:

• trunk/src/org/openstreetmap/josm/tools/Utils.java (modified) (2 diffs)

trunk/src/org/openstreetmap/josm/tools/Utils.java

@@ -401 +401 @@
     }
 
+    private static final char[] HEX_ARRAY = {'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'};
+
     /**
      * Converts a byte array to a string of hexadecimal characters.
@@ -409 +411 @@
      */
     public static String toHexString(byte[] bytes) {
-        char[] hexArray = {'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'};
-        char[] hexChars = new char[bytes.length * 2];
-        for (int j=0; j<bytes.length; j++) {
-            int v = bytes[j] & 0xFF;
-            hexChars[j*2] = hexArray[v/16];
-            hexChars[j*2 + 1] = hexArray[v%16];
+
+        if (bytes == null) {
+            return "";
+        }
+
+        final int len = bytes.length;
+        if (len == 0) {
+            return "";
+        }
+
+        char[] hexChars = new char[len * 2];
+        for (int i = 0, j = 0; i < len; i++) {
+            final int v = bytes[i];
+            hexChars[j++] = HEX_ARRAY[(v & 0xf0) >> 4];
+            hexChars[j++] = HEX_ARRAY[v & 0xf];
         }
         return new String(hexChars);