# HG changeset patch
# User Claus Gittinger <cg@exept.de>
# Date 1412758187 -7200
# Node ID 8e30e6a52a64beed764e3f3fa0e27e2b0b7f0894
# Parent  247352d5de0f0b71235751a5cb4d6d3362e0ef26
class: CharacterArray
added:
        #hash_fnv1a
        #hash_java

diff -r 247352d5de0f -r 8e30e6a52a64 CharacterArray.st
--- a/CharacterArray.st	Sun Oct 05 00:36:59 2014 +0200
+++ b/CharacterArray.st	Wed Oct 08 10:49:47 2014 +0200
@@ -283,7 +283,6 @@
     "Created: 3.8.1997 / 18:16:40 / cg"
 ! !
 
-
 !CharacterArray class methodsFor:'cleanup'!
 
 lowSpaceCleanup
@@ -327,7 +326,6 @@
     "
 ! !
 
-
 !CharacterArray class methodsFor:'pattern matching'!
 
 matchEscapeCharacter
@@ -725,7 +723,6 @@
     ^ self == CharacterArray
 ! !
 
-
 !CharacterArray methodsFor:'Compatibility-ANSI'!
 
 addLineDelimiters
@@ -2242,6 +2239,49 @@
     "Created: / 26-12-2011 / 13:46:06 / cg"
 !
 
+hash_fnv1a
+    "return an integer useful as a hash-key.
+     This method uses the fnv-1a algorithm
+     (which is actually a very good one)"
+
+    |h|
+
+    h := 2166136261.
+    self do:[:eachChar |
+        h := h bitXor:(eachChar codePoint).
+        h := (h * 16777619) bitAnd:16rFFFFFFFF.
+    ].
+    ^ h
+
+    "
+     'abc' hash_fnv1a  
+     'foofooHelloWorld' hash_fnv1a   
+     'blablaHelloWorld' hash_fnv1a   
+    "
+!
+
+hash_java
+    "return an integer useful as a hash-key.
+     This method uses the same algorithm as used in
+     the java virtual machine 
+     (which is actually not a very good one)."
+
+    |h|
+
+    h := 0.
+    self do:[:eachChar |
+        h := (h * 31) + (eachChar codePoint).
+        h := h bitAnd:16rFFFFFFFF.
+    ].
+    ^ h
+
+    "
+     'abc' hash_java  
+     'foofooHelloWorld' hash_java   
+     'blablaHelloWorld' hash_java   
+    "
+!
+
 levenshteinTo:aString
     "return the levenshtein distance to the argument, aString;
      this value corresponds to the number of replacements that have to be
@@ -4129,8 +4169,6 @@
 ! !
 
 
-
-
 !CharacterArray methodsFor:'matching - glob expressions'!
 
 compoundMatch:aString
@@ -4814,7 +4852,6 @@
 ! !
 
 
-
 !CharacterArray methodsFor:'padded copying'!
 
 centerPaddedTo:newSize
@@ -7004,15 +7041,14 @@
     ^ aVisitor visitString:self with:aParameter
 ! !
 
-
 !CharacterArray class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic/CharacterArray.st,v 1.543 2014-10-03 01:48:38 vrany Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/CharacterArray.st,v 1.544 2014-10-08 08:49:47 cg Exp $'
 !
 
 version_CVS
-    ^ '$Header: /cvs/stx/stx/libbasic/CharacterArray.st,v 1.543 2014-10-03 01:48:38 vrany Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/CharacterArray.st,v 1.544 2014-10-08 08:49:47 cg Exp $'
 ! !