//very similar to parent(), but assumes contextRef refers to a singular, existing node in the model
//this means we can do '/a/b/c + ../../d/e/f = /a/d/e/f', which we couldn't do in parent()
//return null if context ref is not absolute, or we parent up past the root node
//NOTE: this function still works even when contextRef contains INDEX_UNBOUND multiplicites... conditions depend on this behavior,
// even though it's slightly icky
public TreeReference anchor(TreeReference contextRef)
{
if (isAbsolute())
{
return(this.clone());
}
else if (!contextRef.isAbsolute())
{
return(null);
}
else
{
TreeReference newRef = contextRef.clone();
int contextSize = contextRef.size();
if (refLevel > contextSize)
{
return(null); //tried to do '/..'
}
else
{
for (int i = 0; i < refLevel; i++)
{
newRef.removeLastLevel();
}
for (int i = 0; i < size(); i++)
{
newRef.add(this.getName(i), this.getMultiplicity(i));
}
return(newRef);
}
}
}
//return a new reference that is this reference anchored to a passed-in parent reference
//if this reference is absolute, return self
//if this ref has 'parent' steps (..), it can only be anchored if the parent ref is a relative ref consisting only of other 'parent' steps
//return null in these invalid situations
public TreeReference parent(TreeReference parentRef)
{
if (isAbsolute())
{
return(this);
}
else
{
TreeReference newRef = parentRef.clone();
if (refLevel > 0)
{
if (!parentRef.isAbsolute() && parentRef.size() == 0)
{
parentRef.refLevel += refLevel;
}
else
{
return(null);
}
}
for (int i = 0; i < names.Count; i++)
{
newRef.add(this.getName(i), this.getMultiplicity(i));
}
return(newRef);
}
}
//return a new reference that is this reference anchored to a passed-in parent reference
//if this reference is absolute, return self
//if this ref has 'parent' steps (..), it can only be anchored if the parent ref is a relative ref consisting only of other 'parent' steps
//return null in these invalid situations
public virtual TreeReference parent(TreeReference parentRef)
{
if (Absolute)
{
return(this);
}
else
{
TreeReference newRef = parentRef.Clone();
if (refLevel > 0)
{
if (!parentRef.Absolute && parentRef.size() == 0)
{
parentRef.refLevel += refLevel;
}
else
{
return(null);
}
}
for (TreeReferenceLevel l: data)
{
newRef.add(l.shallowCopy());
}
return(newRef);
}
}
/**
* clone and extend a reference by one level
* @param ref
* @param name
* @param mult
* @return
*/
public TreeReference extendRef(String name, int mult)
{
//TODO: Shouldn't work for this if this is an attribute ref;
TreeReference childRef = this.clone();
childRef.add(name, mult);
return(childRef);
}
//return a copy of the ref
public TreeReference clone()
{
TreeReference newRef = new TreeReference();
newRef.setRefLevel(this.refLevel);
for (int i = 0; i < this.size(); i++)
{
newRef.add(this.getName(i), this.getMultiplicity(i));
}
return(newRef);
}
public TreeReference relativize(TreeReference parent)
{
if (parent.isParentOf(this, false))
{
TreeReference relRef = selfRef();
for (int i = parent.size(); i < this.size(); i++)
{
relRef.add(this.getName(i), INDEX_UNBOUND);
}
return(relRef);
}
else
{
return(null);
}
}
//return a copy of the ref
//UPGRADE_ISSUE: The equivalent in .NET for method 'java.lang.Object.clone' returns a different type. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1224'"
public virtual System.Object Clone()
{
TreeReference newRef = new TreeReference();
newRef.RefLevel = this.refLevel;
for (TreeReferenceLevel l: data)
{
newRef.add(l.shallowCopy());
}
//copy instances
newRef.InstanceName = instanceName;
newRef.Context = this.contextType;
return(newRef);
}
//very similar to parent(), but assumes contextRef refers to a singular, existing node in the model
//this means we can do '/a/b/c + ../../d/e/f = /a/d/e/f', which we couldn't do in parent()
//return null if context ref is not absolute, or we parent up past the root node
//NOTE: this function still works even when contextRef contains INDEX_UNBOUND multiplicites... conditions depend on this behavior,
// even though it's slightly icky
public virtual TreeReference anchor(TreeReference contextRef)
{
//TODO: Technically we should possibly be modifying context stuff here
//instead of in the xpath stuff;
if (Absolute)
{
return(this.Clone());
}
else if (!contextRef.Absolute)
{
throw new XPathException("Could not resolve " + this.toString(true));
}
else
{
TreeReference newRef = contextRef.Clone();
int contextSize = contextRef.size();
if (refLevel > contextSize)
{
//tried to do '/..'
throw new XPathException("Could not resolve " + this.toString(true));
}
else
{
for (int i = 0; i < refLevel; i++)
{
newRef.removeLastLevel();
}
for (int i = 0; i < size(); i++)
{
newRef.add(data.elementAt(i).shallowCopy());
}
return(newRef);
}
}
}
