Interceptors sort order
Hi
I have found that order of seam interceptors sometimes violates constraints, defined by @Within and @Around annotations.
You can see it if You look at two beans in "booking" example, one with @LoggedIn interceptor another without. The relative position of ConversationInterceptor, BijectionInterceptor changes.
...... ConversationInterceptor, BijectionInterceptor ......
...... BijectionInterceptor, ConversationInterceptor ......
======================================
I have fix it, by reimplementing sorter.
Sorry, if i post it in wrong place.
Changed file (modified function)
org.jboss.seam.Component.java
....
private void initInterceptors()
{
initDefaultInterceptors();
for (Annotation annotation: beanClass.getAnnotations())
{
if ( annotation.annotationType().isAnnotationPresent(Interceptors.class) )
{
interceptors.add( new Interceptor(annotation, this) );
}
}
// new Sorter<Interceptor>() {
// protected boolean isOrderViolated(Interceptor outside, Interceptor inside)
// {
// Class<?> insideClass = inside.getUserInterceptor().getClass();
// Class<?> outsideClass = outside.getUserInterceptor().getClass();
// Around around = insideClass.getAnnotation(Around.class);
// Within within = outsideClass.getAnnotation(Within.class);
// return ( around!=null && Arrays.asList( around.value() ).contains( outsideClass ) ) ||
// ( within!=null && Arrays.asList( within.value() ).contains( insideClass ) );
// }
// }.sort(interceptors);
newSort(interceptors);
log.trace("interceptor stack: " + interceptors);
}
......
Changed file (new function)
org.jboss.seam.Component.java
.......
private List<Interceptor> newSort(List<Interceptor> list){
List<SortItem<Interceptor>> siList = new ArrayList<SortItem<Interceptor>>();
Map<Class<?>,SortItem<Interceptor>> ht = new HashMap<Class<?>,SortItem<Interceptor>>();
for (Interceptor i : list){
SortItem<Interceptor> si = new SortItem<Interceptor>(i);
siList.add(si);
ht.put(i.getUserInterceptor().getClass(),si);
}
for (SortItem<Interceptor> si : siList){
Class<?> clazz = si.getObj().getUserInterceptor().getClass();
Around around = clazz.getAnnotation(Around.class);
Within within = clazz.getAnnotation(Within.class);
if (around!=null){
for (Class<?> cl : Arrays.asList( around.value() ) ){
si.getAround().add( ht.get(cl) );
}
}
if (within!=null){
for (Class<?> cl : Arrays.asList( within.value() ) ){
si.getWithin().add( ht.get(cl) );
}
}
}
//===========//
SorterNew<Interceptor> sList = new SorterNew<Interceptor>();
siList = sList.sort(siList);
//siList = SortItem.sort(siList);
//===========//
list.clear();
for (SortItem<Interceptor> si : siList){
list.add(si.getObj());
}
return list ;
}
.......
New file:
org.jboss.seam.util.SorterNew
package org.jboss.seam.util;
import java.util.ArrayList;
import java.util.List;
public class SorterNew<T> {
private List<SortItem<T>> list = null; //new ArrayList();
public List<SortItem<T>> sort(List<SortItem<T>> lst){
this.list = lst;
List<SortItem<T>> res = new ArrayList<SortItem<T>>();
SortItem<T> inmost = null;
do{
inmost = getInmost();
if (inmost!=null){
res.add(inmost);
remove(inmost);
}
}while(list.size()>0 && inmost!=null);
if (list.size()>0){
throw new RuntimeException("Can not sort interceptors list:"+list.toString());
}
return res;
}
private void remove(SortItem<T> item){
list.remove(item);
for(SortItem<T> o : list){
o.getAround().remove(item);
}
}
private SortItem<T> getInmost() {
SortItem<T> res=null;
for(SortItem<T> o : list){
if ((o.getAround().size()==0) && testNobodyWantsWithin(o) ){
res = o;
break;
}
}
return res;
}
private boolean testNobodyWantsWithin(SortItem<T> item){
boolean res = true;
for (SortItem<T> o : list){
if (o.getWithin().contains(item)){
res = false;
break;
}
}
return res;
}
}
[New file:
org.jboss.seam.util.SortItem
package org.jboss.seam.util;
import java.util.ArrayList;
import java.util.List;
public class SortItem<T> {
private T obj;
private List<SortItem> around = new ArrayList<SortItem>();
private List<SortItem> within = new ArrayList<SortItem>();
public SortItem(T obj){
this.obj = obj;
}
public T getObj(){
return obj;
}
public List<SortItem> getAround() {
return around;
}
public List<SortItem> getWithin() {
return within;
}
}
