> I think the actual problem is not in the StringBuffer size, but in the
> copy done when the buffer is un-shared; after all, unless the StringBuffer
> jump down from 1Mb to 1 byte, a single instance would not be a big problem;
> but having many tokens with a lot of wasted memory would be ...
I whipped up a quick patch for this... I tested it so I know that it
doesn't break anything new. However, I don't know if it will fix your
problem. :)
Basically, in the String(StringBuffer) constructor, I copy the
stringbuffer's contents if used + SLOP < buffer.length.
For systems that create a string buffer, stringize it, and then throw
away the string buffer, this may introduce an extra copy while only
saving a small amount of memory.
-Pat
----- ----- ---- --- --- -- - - - - -
Pat Tullmann [EMAIL PROTECTED]
Don't hate yourself in the morning -- sleep until noon!
Index: String.java
===================================================================
RCS file: /cvs/kaffe/kaffe/libraries/javalib/java/lang/String.java,v
retrieving revision 1.27
diff -u -u -r1.27 String.java
--- String.java 1999/10/12 02:29:47 1.27
+++ String.java 1999/12/18 23:46:43
@@ -20,6 +20,12 @@
final public class String implements Serializable, Comparable {
+ /**
+ * Maximum slop (extra unused chars in the char[]) that
+ * will be accepted in a StringBuffer -> String conversion.
+ */
+ private static final int STRINGBUFFER_SLOP = 32;
+
// Note: value, offset, and count are not private, because
// StringBuffer uses them for faster access
char[] value;
@@ -52,11 +58,23 @@
public String (StringBuffer sb) {
- // mark this StringBuffer so that it knows we are using it
+ // mark the StringBuffer so that it knows we are using it
sb.isStringized = true;
+
+ if ((sb.used + STRINGBUFFER_SLOP) > sb.buffer.length) {
+ value = new char[sb.used];
+ System.arraycopy(sb.buffer, 0,
+ value, 0, sb.used);
+ count = sb.used;
- count = sb.used;
- value = sb.buffer;
+ // StringBuffer is free to reuse its buffer again
+ sb.isStringized = false;
+ }
+ else {
+ // Just point directly to the StringBuffer's char[]
+ count = sb.used;
+ value = sb.buffer;
+ }
}
public String( byte[] bytes) {
