public void signalReady ( Constraints viewConstraints ) { try { rootFileSystem . mkdirs ( signalDirectory ) ; } catch ( IOException e ) { throw new DatasetIOException ( "Unable to create signal manager directory: " + signalDirectory , e ) ; } String normalizedConstraints = getNormalizedConstraints ( viewConstraints ) ; Path signalPath = new Path ( signalDirectory , normalizedConstraints ) ; try { // create the output stream to overwrite the current contents, if the directory or file // exists it will be overwritten to get a new timestamp FSDataOutputStream os = rootFileSystem . create ( signalPath , true ) ; os . close ( ) ; } catch ( IOException e ) { throw new DatasetIOException ( "Could not access signal path: " + signalPath , e ) ; } }
Create a signal for the specified constraints .