diff options
| author | andreast <andreast@138bc75d-0d04-0410-961f-82ee72b054a4> | 2004-09-21 13:50:13 +0000 |
|---|---|---|
| committer | andreast <andreast@138bc75d-0d04-0410-961f-82ee72b054a4> | 2004-09-21 13:50:13 +0000 |
| commit | 62e8d0c9c16b08f9adf9649b5e72cb13ea2bbdf6 (patch) | |
| tree | adb823d7896f1493d35bab1cf7e20fb7b557415c /libjava/java/nio/ByteBuffer.java | |
| parent | 2b573e698aa85c2c56a05e9657d12eeac27acf69 (diff) | |
| download | ppe42-gcc-62e8d0c9c16b08f9adf9649b5e72cb13ea2bbdf6.tar.gz ppe42-gcc-62e8d0c9c16b08f9adf9649b5e72cb13ea2bbdf6.zip | |
2004-09-21 Sven de Marothy <sven@physto.se>
* java/nio/ByteBuffer.java (hashCode): Implemented.
* java/nio/CharBuffer.java: Likewise.
* java/nio/DoubleBuffer.java: Likewise.
* java/nio/FloatBuffer.java: Likewise.
* java/nio/LongBuffer.java: Likewise.
* java/nio/IntBuffer.java: Likewise.
* java/nio/ShortBuffer.java: Likewise.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@87804 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'libjava/java/nio/ByteBuffer.java')
| -rw-r--r-- | libjava/java/nio/ByteBuffer.java | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/libjava/java/nio/ByteBuffer.java b/libjava/java/nio/ByteBuffer.java index 378e58827fa..e502e003199 100644 --- a/libjava/java/nio/ByteBuffer.java +++ b/libjava/java/nio/ByteBuffer.java @@ -260,11 +260,27 @@ public abstract class ByteBuffer extends Buffer /** * Calculates a hash code for this buffer. + * + * This is done with <code>int</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 */ public int hashCode () { - // FIXME: Check what SUN calculates here. - return super.hashCode (); + int hashCode = get(position()) + 31; + int multiplier = 1; + for (int i = position() + 1; i < limit(); ++i) + { + multiplier *= 31; + hashCode += (get(i) + 30)*multiplier; + } + return hashCode; } /** |
