Review Request: CR 7100996 - (spec str) IndexOutOfBoundsException when using a StringBuffer from multiple threads

[Jim Gish]

Taking all the previous comments into consideration, here's an update:

diff -r fc575c78f5d3 src/share/classes/java/lang/StringBuffer.java
--- a/src/share/classes/java/lang/StringBuffer.java    Sun Jun 10 
10:29:27 2012 +0100
+++ b/src/share/classes/java/lang/StringBuffer.java    Thu Jun 21 
14:09:17 2012 -0400
@@ -63,6 +63,16 @@
   * appending or inserting from a source sequence) this class synchronizes
   * only on the string buffer performing the operation, not on the source.
   * <p>
+ * While <code>StringBuffer</code> is designed to be safe to use
+ * concurrently from multiple threads, the source data passed to create,
+ * i.e. <code>StringBuffer(source)</code>, <code>append(source)</code>,
+ * or <code>insert(source)</code>, if shared across threads, must ensure
+ * that <code>create/append/insert</code> has a consistent and unchanging
+ * view of the source data for the duration of the operation.  This could
+ * be done by the caller holding a lock during the
+ * <code>create/append/insert</code> call, or because the source data is
+ * immutable, or because the source data is not shared across threads.
+ * <p>
   * Every string buffer has a capacity. As long as the length of the
   * character sequence contained in the string buffer does not exceed
   * the capacity, it is not necessary to allocate a new internal

Thanks,
    Jim

On 06/21/2012 12:49 PM, David Schlosnagle wrote:
> On Thu, Jun 21, 2012 at 11:59 AM, Jim Gish<jim.gish at oracle.com>  wrote:
>> + * across threads, must ensure that StringBuffer.add/insert has a
> Jim,
>
> You may want to replace "add" with "append" if you are intending to
> reference the actual method name and not the generic operation.
> Additionally, you may want to use {@code ...} to show this context.
>
> Thanks,
> Dave

-- 
Jim Gish | Consulting Member of Technical Staff | +1.781.442.0304
Oracle Java Platform Group | Core Libraries Team
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