private void checkRepository() throws NotConnectedException {
		if (repository == null) {
			throw new NotConnectedException("Not connected to the server");
		}
	}
Verify that the connection is still valid.
@return true if the connection is valid; false if the connection needs to be reestablished
Ghidra/Framework/FileSystem/src/main/java/ghidra/framework/client/RepositoryAdapter.java