@Override
	public Map<String, DataSet<?>> getBroadcastSets() {
		return this.broadcastVariables == null ?
				Collections.<String, DataSet<?>>emptyMap() :
				Collections.unmodifiableMap(this.broadcastVariables);
	}
@ Override public Map < String , DataSet < ? > > getBroadcastSets ( ) { return this . broadcastVariables == null ? Collections . < String , DataSet < ? > > emptyMap ( ) : Collections . unmodifiableMap ( this . broadcastVariables ) ; }
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