Exception Thrown: java.lang.NullPointerException: Cannot invoke "GraphADT.getNodeCount()" because "this.graph" is null
java.lang.NullPointerException: Cannot invoke "GraphADT.getNodeCount()" because "this.graph" is null
	at Backend.loadGraphData(Backend.java:28)
	at WebApp.createWorkingFrontend(WebApp.java:116)
	at WebApp.handleSingleResponse(WebApp.java:173)
	at WebApp.main(WebApp.java:47)