@NotNull
public String getNamespaceByPrefix(String prefix) {
final PsiElement parent = getParent();
LOG.assertTrue(parent.isValid());
BidirectionalMap<String, String> map = initNamespaceMaps(parent);
if (map != null) {
final String ns = map.get(prefix);
if (ns != null) return ns;
}
if (parent instanceof XmlTag) return ((XmlTag) parent).getNamespaceByPrefix(prefix);
// The prefix 'xml' is by definition bound to the namespace name
// http://www.w3.org/XML/1998/namespace. It MAY, but need not, be declared
if (XML_NS_PREFIX.equals(prefix)) return XmlUtil.XML_NAMESPACE_URI;
if (prefix.length() > 0 && !hasNamespaceDeclarations() && getNamespacePrefix().equals(prefix)) {
// When there is no namespace declarations then qualified names should be just used in dtds
// this implies that we may have "" namespace prefix ! (see last paragraph in Namespaces in
// Xml, Section 5)
String result =
ourGuard.doPreventingRecursion(
"getNsByPrefix",
true,
new Computable<String>() {
@Override
public String compute() {
final String nsFromEmptyPrefix = getNamespaceByPrefix("");
final XmlNSDescriptor nsDescriptor = getNSDescriptor(nsFromEmptyPrefix, false);
final XmlElementDescriptor descriptor =
nsDescriptor != null
? nsDescriptor.getElementDescriptor(XmlTagImpl.this)
: null;
final String nameFromRealDescriptor =
descriptor != null
&& descriptor.getDeclaration() != null
&& descriptor.getDeclaration().isPhysical()
? descriptor.getName()
: "";
if (nameFromRealDescriptor.equals(getName())) return nsFromEmptyPrefix;
return XmlUtil.EMPTY_URI;
}
});
if (result != null) {
return result;
}
}
return XmlUtil.EMPTY_URI;
}
