Tony,
I'm not sure I understand you completely. I didn't find any places in
the spec that require creation of a new MessageFormat instance.
However, at the same by looking at the code I see that such
implementation of caching is inefficient by itself because
format.toPattern() has the same (or even greater) level of complexity
if compared with MessageFormat's constructor. So I tend to agree that
creation of a new instance makes sense here.
Alexei
2008/2/19, Tony Wu <[EMAIL PROTECTED]>:
> Hi, Alexei
> Actually your proposal doesn't work, the problem is that we can not
> caching a format instance here rather than the caching mechanism. Each
> call to this static method must create a new instance of MessageFormat
> (which has been done by ICU already) then do the formating in order to
> sync the access to instance variable otherwise we need synchronize the
> format method itself. Obviously creating a new instance has higher
> performance.
>
> On 2/19/08, Alexei Zakharov <[EMAIL PROTECTED]> wrote:
> > Hi Tony,
> >
> > Don't you think that placing a synchronized block around the existing
> > code would be a more transparent fix rather than simply redirecting
> > all job to ICU? I mean something like this:
> >
> > Index: src/main/java/java/text/MessageFormat.java
> > ===================================================================
> > --- src/main/java/java/text/MessageFormat.java (revision 628711)
> > +++ src/main/java/java/text/MessageFormat.java (working copy)
> > @@ -446,6 +446,8 @@
> > * when the pattern cannot be parsed
> > */
> > public static String format(String template, Object... objects) {
> > + String result;
> > +
> > if (objects != null) {
> > for (int i = 0; i < objects.length; i++) {
> > if (objects[i] == null) {
> > @@ -453,12 +455,16 @@
> > }
> > }
> > }
> > - if (format == null) {
> > - format = new com.ibm.icu.text.MessageFormat(template);
> > - } else if (!template.equals(format.toPattern())){
> > - format.applyPattern(template);
> > + synchronized (MessageFormat.class) {
> > + if (format == null) {
> > + format = new com.ibm.icu.text.MessageFormat(template);
> > + } else if (!template.equals(format.toPattern())){
> > + format.applyPattern(template);
> > + }
> > + result = format.format(objects);
> > }
> > - return format.format(objects);
> > +
> > + return result;
> > }
> >
> > /**
> >
> >
> > Thanks,
> > Alexei
> >
> > 2008/2/19, Tony Wu <[EMAIL PROTECTED]>:
> > > This is a major problem which blocks MessageFormat running on
> > > multi-thread platform. It fails because the caching in Harmony does
> > > not work with ICU4j 3.8.1. I suggest to commit this patch for M5.
> > >
> > > --
> > > Tony Wu
> > > China Software Development Lab, IBM
> > >
> >
>
>
> --
> Tony Wu
> China Software Development Lab, IBM
>
