DepthFirstSearch dfs = new DepthFirstSearch(cfg).search();   ValueNumberAnalysis vna = new ValueNumberAnalysis(methodGen, dfs); ValueNumberDataflow vnaDataflow = new ValueNumberDataflow(cfg, vna); vnaDataflow.execute();  IsNullValueAnalysis analysis = new IsNullValueAnalysis(methodGen, cfg, vnaDataflow, dfs); return analysis;
return classContext.getIsNullValueDataflow(method);
	public static void main(String[] argv) throws Exception {		if (argv.length != 1) {			System.err.println("Usage: " + IsNullValueAnalysis.class.getName() + " <class file>");			System.exit(1);		}		DataflowTestDriver<IsNullValueFrame, IsNullValueAnalysis> driver = new DataflowTestDriver<IsNullValueFrame, IsNullValueAnalysis>() {			public IsNullValueAnalysis createAnalysis(MethodGen methodGen, CFG cfg)				throws DataflowAnalysisException {				DepthFirstSearch dfs = new DepthFirstSearch(cfg).search();				// Create the ValueNumberAnalysis				ValueNumberAnalysis vna = new ValueNumberAnalysis(methodGen, dfs);				ValueNumberDataflow vnaDataflow = new ValueNumberDataflow(cfg, vna);				vnaDataflow.execute();				IsNullValueAnalysis analysis = new IsNullValueAnalysis(methodGen, cfg, vnaDataflow, dfs);				return analysis;			}		};		driver.execute(argv[0]);	}