protected SchemaDocumentImpl(SchemaImpl schema,
    String _schemaDocumentURI) 
{
         
        this.schema = schema;
        this.schemaDocumentURI = _schemaDocumentURI;
}

 public boolean equals(Object o) 
{
        SchemaDocumentImpl rhs = (SchemaDocumentImpl) o;
        if( this.schemaDocumentURI==null || rhs.schemaDocumentURI==null)
            return this==rhs;
        if(!schemaDocumentURI.equals(rhs.schemaDocumentURI) )
            return false;
        return this.schema==rhs.schema;
}

 public Set getImportedDocuments(String targetNamespace) 
{
        if(targetNamespace==null)
            throw new IllegalArgumentException();
        Set< SchemaDocument > r = new HashSet< SchemaDocument >();
        for (SchemaDocumentImpl doc : references) {
            if(doc.getTargetNamespace().equals(targetNamespace))
                r.add(doc);
        }
        return Collections.unmodifiableSet(r);
}

 public Set getIncludedDocuments() 
{
        return getImportedDocuments(this.getTargetNamespace());
}

 public Set getReferencedDocuments() 
{
        return Collections.< SchemaDocument >unmodifiableSet(references);
}

 public Set getReferers() 
{
        return Collections.< SchemaDocument >unmodifiableSet(referers);
}

 public SchemaImpl getSchema() 
{
        return schema;
}

 public String getSystemId() 
{
        return schemaDocumentURI;
}

 public String getTargetNamespace() 
{
        return schema.getTargetNamespace();
}

 public int hashCode() 
{
        if(schemaDocumentURI==null)
            return super.hashCode();
        return schemaDocumentURI.hashCode()^this.schema.hashCode();
}

 public boolean imports(SchemaDocument doc) 
{
        if(!references.contains(doc))
            return false;
        return doc.getSchema()!=schema;
}

 public boolean includes(SchemaDocument doc) 
{
        if(!references.contains(doc))
            return false;
        return doc.getSchema()==schema;
}