package org.exolab.castor.xml;
import java.util.Hashtable;
import java.util.Map;
/**
* Default {@link IDResolver} for Castor XML during (un)marshaling.
* @see org.exolab.castor.xml.IDResolver
*/
class IDResolverImpl implements IDResolver {
/**
* A collection of IDREF --> target object mappings
*/
private Map _idReferences = new Hashtable();
/**
* A custom (user-injected) IDResolver instance to be used
* for IDREF resolution.
*/
private IDResolver _idResolver = null;
/**
* Binds a mapping from an ID to the referenced target object.
* @param id
* Object identifier
* @param object
* Object being identified by ID
* @param _validate True if validation is enabled.
* @throws ValidationException
* If an ID is used more than once.
*/
void bind(final String id, final Object object, final boolean isValidating)
throws ValidationException {
if (isValidating && id == null) {
throw new ValidationException ("Invalid ID value 'null' encountered");
}
if (isValidating && id.equals("")) {
throw new ValidationException ("Empty ID value encountered");
}
if (isValidating && _idReferences.containsKey(id)) {
if (!(id.equals("org.exolab.castor.mapping.MapItem") ||
id.equals("HIGH-LOW"))) {
throw new ValidationException("Duplicate ID " + id + " encountered");
}
} else {
_idReferences.put(id, object);
}
}
/**
* Returns the Object whose id matches the given IDREF, or 'null' if no
* object was found.
*
* @param idref
* the IDREF to resolve.
* @return the Object whose id matches the given IDREF.
*/
public Object resolve(final String idref) {
Object object = _idReferences.get(idref);
if (object != null) {
return object;
}
if (_idResolver != null) {
return _idResolver.resolve(idref);
}
return null;
}
/**
* Sets a custom IDResolver instance to be used for IDRef resolution.
* @param idResolver a custom IDResolver instance to be used.
*/
void setResolver(IDResolver idResolver) {
_idResolver = idResolver;
}
}
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