/**
* Resolves to penultimate context named by 'name'. Returns true if penultimate context has been
* reached (i.e. name only has one atomic component left). Returns false otherwise, and sets
* Continuation to parts of name not yet resolved.
*/
protected boolean resolve_to_penultimate_context(Name name, Continuation cont)
throws NamingException {
String target = name.toString();
if (debug > 0) System.out.println("RESOLVE TO PENULTIMATE" + target);
StringHeadTail ht = c_parseComponent(target, cont);
String tail = ht.getTail();
String head = ht.getHead();
if (head == null) {
// something is wrong; no name at all
InvalidNameException e = new InvalidNameException();
throw cont.fillInException(e);
}
if (!isEmpty(tail)) {
// more components; hence not at penultimate context yet
try {
Object headCtx = a_lookup(head, cont);
if (headCtx != null) cont.setContinue(headCtx, head, this, tail);
else if (cont.isContinue()) cont.appendRemainingComponent(tail);
} catch (NamingException e) {
e.appendRemainingComponent(tail);
throw e;
}
} else {
// already at penultimate context
cont.setSuccess(); // clear
return true;
}
return false;
}
/**
* Resolve to context named by 'name'. Returns true if at named context (i.e. 'name' is empty
* name). Returns false otherwise, and sets Continuation on parts of 'name' not yet resolved.
*/
protected boolean resolve_to_context(Name name, Continuation cont) throws NamingException {
String target = name.toString();
StringHeadTail ht = c_parseComponent(target, cont);
String tail = ht.getTail();
String head = ht.getHead();
if (debug > 0)
System.out.println("RESOLVE TO CONTEXT(" + target + ") = {" + head + ", " + tail + "}");
if (head == null) {
// something is wrong; no name at all
InvalidNameException e = new InvalidNameException();
throw cont.fillInException(e);
}
if (!isEmpty(head)) {
// if there is head is a non-empty name
// this means more resolution to be done
try {
Object headCtx = a_lookup(head, cont);
// System.out.println("answer " + headCtx);
if (headCtx != null) cont.setContinue(headCtx, head, this, (tail == null ? "" : tail));
else if (cont.isContinue()) cont.appendRemainingComponent(tail);
} catch (NamingException e) {
e.appendRemainingComponent(tail);
throw e;
}
} else {
cont.setSuccess(); // clear
return true;
}
return false;
}
/** Resolves to nns associated with 'name' and set Continuation to the result. */
protected void resolve_to_nns_and_continue(Name name, Continuation cont) throws NamingException {
if (debug > 0) System.out.println("RESOLVE TO NNS AND CONTINUE" + name.toString());
if (resolve_to_penultimate_context_nns(name, cont)) {
Object nns = a_lookup_nns(name.toString(), cont);
if (nns != null) cont.setContinue(nns, name, this);
}
}
protected Object c_lookup(Name name, Continuation cont) throws NamingException {
Object ret = null;
if (resolve_to_penultimate_context(name, cont)) {
ret = a_lookup(name.toString(), cont);
if (ret != null && ret instanceof LinkRef) {
cont.setContinue(ret, name, this);
ret = null;
}
}
return ret;
}
/**
* Resolves the nns for 'name' when the named context is acting as an intermediate context.
*
* <p>For a system that supports junctions, this would be equilvalent to a_lookup(name, cont);
* because for junctions, an intermediate slash simply signifies a syntactic separator.
*
* <p>For a system that supports implicit nns, this would be equivalent to a_lookup_nns(name,
* cont); because for implicit nns, a slash always signifies the implicit nns, regardless of
* whether it is intermediate or trailing.
*
* <p>By default this method supports junctions, and also allows for an implicit nns to be
* dynamically determined through the use of the "nns" reference (see a_processJunction_nns()).
* Contexts that implement implicit nns directly should provide an appropriate override.
*/
protected Object a_resolveIntermediate_nns(String name, Continuation cont)
throws NamingException {
try {
final Object obj = a_lookup(name, cont);
// Do not append "" to Continuation 'cont' even if set
// because the intention is to ignore the nns
//
if (obj != null && getClass().isInstance(obj)) {
// If "obj" is in the same type as this object, it must
// not be a junction. Continue the lookup with "/".
cont.setContinueNNS(obj, name, this);
return null;
} else if (obj != null && !(obj instanceof Context)) {
// obj is not even a context, so try to find its nns
// dynamically by constructing a Reference containing obj.
RefAddr addr =
new RefAddr("nns") {
public Object getContent() {
return obj;
}
private static final long serialVersionUID = -3399518522645918499L;
};
Reference ref = new Reference("java.lang.Object", addr);
// Resolved name has trailing slash to indicate nns
CompositeName resName = new CompositeName();
resName.add(name);
resName.add(""); // add trailing slash
// Set continuation leave it to
// PartialCompositeContext.getPCContext() to throw CPE.
// Do not use setContinueNNS() because we've already
// consumed "/" (i.e., moved it to resName).
cont.setContinue(ref, resName, this);
return null;
} else {
return obj;
}
} catch (NamingException e) {
e.appendRemainingComponent(""); // add nns back
throw e;
}
}
protected Object c_lookup_nns(Name name, Continuation cont) throws NamingException {
if (_contextType == _ATOMIC) {
Object ret = null;
if (resolve_to_penultimate_context_nns(name, cont)) {
ret = a_lookup_nns(name.toString(), cont);
if (ret != null && ret instanceof LinkRef) {
cont.setContinue(ret, name, this);
ret = null;
}
}
return ret;
} else {
return super.c_lookup_nns(name, cont);
}
}
/**
* This function is used when implementing a naming system that supports junctions. For example,
* when the a_list_nns(newobj) method is invoked, that means the caller is attempting to list the
* the nns context of of this context. For a context that supports junctions, it by default does
* not have any nns. Consequently, a NameNotFoundException is thrown.
*/
protected void a_processJunction_nns(Continuation cont) throws NamingException {
// Construct a new Reference that contains this context.
RefAddr addr =
new RefAddr("nns") {
public Object getContent() {
return AtomicContext.this;
}
private static final long serialVersionUID = 3449785852664978312L;
};
Reference ref = new Reference("java.lang.Object", addr);
// Set continuation leave it to PartialCompositeContext.getPCContext()
// to throw the exception.
// Do not use setContinueNNS() because we've are
// setting relativeResolvedName to "/".
cont.setContinue(ref, _NNS_NAME, this);
}
