diff options
Diffstat (limited to 'libjava/java/nio/LongBuffer.java')
| -rw-r--r-- | libjava/java/nio/LongBuffer.java | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/libjava/java/nio/LongBuffer.java b/libjava/java/nio/LongBuffer.java index c4066b1..6e9ef34 100644 --- a/libjava/java/nio/LongBuffer.java +++ b/libjava/java/nio/LongBuffer.java @@ -243,11 +243,27 @@ public abstract class LongBuffer extends Buffer /** * Calculates a hash code for this buffer. + * + * This is done with <code>long</code> arithmetic, + * where ** represents exponentiation, by this formula:<br> + * <code>s[position()] + 31 + (s[position()+1] + 30)*31**1 + ... + + * (s[limit()-1]+30)*31**(limit()-1)</code>. + * Where s is the buffer data. Note that the hashcode is dependent + * on buffer content, and therefore is not useful if the buffer + * content may change. + * + * @return the hash code (casted to int) */ public int hashCode () { - // FIXME: Check what SUN calculates here. - return super.hashCode (); + long hashCode = get(position()) + 31; + long multiplier = 1; + for (int i = position() + 1; i < limit(); ++i) + { + multiplier *= 31; + hashCode += (get(i) + 30)*multiplier; + } + return ((int)hashCode); } /** |