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[ejb-spec users] [jsr345-experts] Re: [Fwd: [ejb-spec issues] [JIRA] Commented: (EJB_SPEC-9) Introduction of @MaxConcurrency annotation]

From: Carlo de Wolf <cdewolf_at_redhat.com>
Date: Fri, 04 May 2012 10:44:00 +0200

Adam,

The proposal doesn't mimic the original one:
http://java.net/projects/ejb-spec/lists/jsr345-experts/archive/2012-04/message/15

Why are non-async & Singleton invocations an issue?

Carlo

On 05/03/2012 09:06 PM, Marina Vatkina wrote:
> Experts,
>
> Do you:
> a) agree with the proposal
> b) disagree with the proposal
> c) have another proposal (please provide one)
> d) would like to modify the proposal (be specific in this case)
>
> thanks,
> -marina
>
> -------- Original Message --------
> Subject: [ejb-spec issues] [JIRA] Commented: (EJB_SPEC-9)
> Introduction of @MaxConcurrency annotation
> Date: Thu, 3 May 2012 05:24:22 +0000 (GMT+00:00)
> From: abien (JIRA) <jira-no-reply_at_java.net>
> Reply-To: issues_at_ejb-spec.java.net
> To: issues_at_ejb-spec.java.net
>
>
>
> [
> http://java.net/jira/browse/EJB_SPEC-9?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=338919#action_338919
> ]
> abien commented on EJB_SPEC-9:
> ------------------------------
>
> Proposal:
>
> @MaxConcurrency annotation as well as the <max-concurrency> element in
> the ejb-jar.xml specify the maximum number of requests handled by a
> given bean class. After the configured number of concurrent requests
> is reached, the container throws a
> javax.ejb.MaxConcurrencyExceededException. A @MaxConcurrency value of
> -1 indicates an infinite amount of concurrency. Max Concurrency
> applies on classes, to specify per bean concurrency, as well as
> @Asynchronous methods. Max Concurrency is neither applicable on
> synchronous methods [I guess without this restriction, the feature
> would be harder to implement by the container provider], nor on
> @Singleton beans.
>
>
>
> public class MaxConcurrencyExceededException extends EJBException{
>
> public MaxConcurrencyExceededException(String message, Exception ex) {
> super(message, ex);
> }
>
> public MaxConcurrencyExceededException(Exception ex) {
> super(ex);
> }
>
> public MaxConcurrencyExceededException(String message) {
> super(message);
> }
>
> public MaxConcurrencyExceededException() {
> }
> }
>
>
> @Documented
> @Target({ElementType.METHOD, ElementType.TYPE})
> @Retention(RetentionPolicy.RUNTIME)
> public @interface MaxConcurrency {
> /**
> * Specifies the maximum concurrency of an EJB or asynchronous
> method <br/>
> * -1 is the default. A negative value means infinite number of
> requests.
> */
> int value() default -1;
> }
>
> Default: -1 infinite.
>
>> Introduction of @MaxConcurrency annotation
>> ------------------------------------------
>>
>> Key: EJB_SPEC-9
>> URL: http://java.net/jira/browse/EJB_SPEC-9
>> Project: ejb-spec
>> Issue Type: New Feature
>> Affects Versions: 3.2
>> Reporter: abien
>> Attachments: MaxConcurrency.zip
>>
>>
>> Currently proprietary max-pool-size settings are used to control the
>> max concurrency of an application and so to prevent overloading the
>> application server.
>> We could abstract the intended behavior into an annotation:
>> @Target(value = {ElementType.METHOD, ElementType.TYPE})
>> @Retention(value = RetentionPolicy.RUNTIME)
>> public @interface MaxConcurrency {
>> public int value() default 30;
>> }
>> We could provide more generic annotation like:
>> @Target(value = {ElementType.METHOD, ElementType.TYPE})
>> @Retention(value = RetentionPolicy.RUNTIME)
>> public @interface Concurrency {
>> public int max() default 30;
>> }
>> to support future extensions. This functionality should be available
>> for EJB 3.2 and CDI.
>