The following shorthand is used to indicate specific annotations:

• Jm: A Java method annotated by annotations with SIP meta annotations.

• Sm: A @SipMethod annotation.

• Sr: A @SipResponseRange annotation.

• Sc: A @SipResponseCode annotation.

• Sp: A @SipPredicate annotation.

• ESm: (Method of the SipServletMessage) eq (value of Sm)

• ESr: (Status code of the SipServletResponse) in (range of Sr)

• Esc: (Status code of the SipServletResponse) eq (value of Sc)

• ESp: Result of evaluation of @SipPredicate.

Converged Application Server determine that a Jm meets the selection criteria if the annotations evaluate the following equation to true. If an annotation is not present in a sub-expression, the equation evaluates to true. Example 3-9 shows the complete precedence rules equation.

(ESm-1|| ESm-2 ||..||ESm-n) && ((ESc-1 || ESc-2 ||..||ESc-n) ||(ESr-1 || ESr-2 || ..||ESr-n)) && (ESp-1 || ESp-2||..||ESp-n)

If more than one Jm meets the selection criteria, Converged Application Server selects the Jm with the smallest count of Sm. If the number of Sms is equal, the container selects the Jm with the smallest count of Sc. If the number of Scs are equal, the container selects the one with the shortest span of Srs.

The following rules apply to requests:

• Sc (SipResponseCode) and Sr (SipResponseRange) are not applicable to Requests.

• If none of the methods satisfy the basic rule, the container selects a Java method annotated with @AnyMethod.

• If none of the above is true, it results in the default behavior as specified by the section 2.3 of JSR-359.

The following rule applies to responses:

• If none of the methods satisfy the basic rule, the container selects a Java method annotated with @AnyMethod.

If an application includes one or more @SipPredicate annotations, the application must ensure that the predicates are not written so as to cause conflict during selection of methods.

During deployment, Converged Application Server scans the annotations present. If more than one Java method has the same SIP meta-annotation specificity using @SipMethod, @SipResponseCode, or @SipResponseRange, the container fails the deployment.

The following examples explain which method is selected when there is more than one Java method that match the selection criteria.

In Example 3-10, for a 200/INVITE response, Converged Application Server selects handleResponse01(), since that is the more specific of the two methods for that message. For a message with another SIP method, the container will select handleResponse02().

@Invite
@SuccessResponse
public void handleResponse01(SipServletResponse response) {
  //...
}

@SuccessResponse
public void handleResponse02(SipServletResponse response) {
  //...
}

In Example 3-11, for a 200/INVITE response, the container will select handleResponse02(), since that is the more specific of the two methods for that message. For 201/INVITE message, the container will select handleResponse01().

@Invite
@SuccessResponse
public void handleResponse01(SipServletResponse response) {
  //...
}

@InviteOkResponse
public void handleResponse02(SipServletResponse response) {
  //...
}
@Retention(RetentionPolicy.RUNTIME)
@Target(METHOD)
@SipResponseCode(200)
@SipMethod("INVITE")
@interface InviteOkResponse { }

In Example 3-12, for a 200 response handleResponse03() is selected since that is the only method that matches the response codes, and, therefore, there is no conflict. For a 201 response, both handleResponse01() and handleResponse02() match the criteria. However since handleResponse01() has a shorter response range than handleResponse02(), Converged Application Server chooses handleResponse01(). For a 302 response, Converged Application Server selects handleResponse02() since that is the only method that match the criteria.

@SuccessResponse
public void handleResponse01(SipServletResponse resp ) {
  //...
}

@NonFailureResponses
public void handleResponse02(SipServletResponse resp) {
  //...
}

@OkResponse
public void handleResponse03(SipServletResponse resp ) {
  //...
}
@Retention(RUNTIME)
@Target(METHOD)
@SipResponseRange(begin = 100, end = 399)
@interface NonFailureResponses { }
@Retention(RUNTIME)
@Target(METHOD)
@SipResponseCode(200)
@interface OkResponse { }

The following examples show situations in which containers fail deployment since method precedence cannot be determined.

In Example 3-13, the container fails the deployment, since both the methods contain the same number of requests, and, for an INVITE request, the container will find two methods with the same specificity.

@Invite
@Message
public void handleRequest01(SipServletRequest req) {
  //...
}

@Invite
@Register
public void handleRequest02(SipServletRequest req) {
  //...
}

In Example 3-14, the container fails deployment because the handleResponse02() supports both SUBSCRIBE and INFO methods and 200 and 204 responses. The handleResponse01() method supports SUBSCRIBE and OPTIONS methods and 200 and 201 responses. Hence, for 200/SUBSCRIBE responses, the specificity of the SIP meta annotations is the same.

@OptionsOkResponse
@SubscribeAccept
public void handleResponse01(SipServletResponse resp) {
  //...
}

@InfoOkResponse
@SubscribeNoNotification
public void handleResponse02(SipServletResponse resp) {
  //...
}
@Retention(RUNTIME)
@Target(METHOD)
@SipResponseCode(200)
@SipMethod("INFO")
@interface InfoOkResponse { }
@Retention(RUNTIME)
@Target(METHOD)
@SipResponseCode(200)
@SipMethod("OPTIONS")
@interface OptionsOkResponse { }
@Retention(RUNTIME)
@Target(METHOD)
@SipResponseCode(204)
@SipMethod("SUBSCRIBE")
@interface SubscribeNoNotification { }
@Retention(RUNTIME)
@Target(METHOD)
@SipResponseCode(201)
@SipMethod("SUBSCRIBE")
@interface SubscribeAccept { }

In Example 3-15, the span of the response ranges are exactly the same and all other SIP meta annotations are the same in both the methods. For overlapping responses, SIP meta annotations in the two methods have the same specificity, and the container fails deployment.

@InviteNonFailureResponses
public void handleResponse01(SipServletResponse resp) {
  //...
}
@Invite
@NonFailureFinalResponses
public void handleResponse02(SipServletResponse resp) {
  //...
}
@Retention(RUNTIME)
@Target(METHOD)
@SipResponseRange(begin = 100, end = 299)
@SipMethod("INVITE")
@interface InviteNonFailureResponses { }
@Retention(RUNTIME)
@Target(METHOD)
@SipResponseRange(begin = 200, end = 399)
@interface NonFailureFinalResponses { }

In Example 3-16, since all the SIP meta annotations of both methods are the same and the @SipPredicate annotation uses the same class, the container fails deployment.

@Invite
@MySpecialResponses
public void handleResponse01(SipServletResponse resp) {
  //...
}
@InviteSpecialResponses
public void handleResponse02(SipServletResponse resp) {
  //...
}
@Retention(RUNTIME)
@Target(METHOD)
@SipMethod("INVITE")
@SipPredicate(MyPredicate.class)
@interface InviteSpecialResponses { }
@Retention(RUNTIME)
@Target(METHOD)
@SipPredicate(MyPredicate.class)
@interface MySpecialResponses { }
class MyPredicate implements Predicate<SipServletResponse> {
  @Override public boolean apply(SipServletResponse response) {
    //...
  }
}