#vulnerable code 
                             public static void main(String[] args) {
		AppUtil appUtil = new AppUtil();
		AService service = (AService) appUtil.getComponentInstance("aService");
		AggregateRootA aggregateRootA = service.getAggregateRootA("11");
		DomainMessage res = service.commandA("11", aggregateRootA, 100);

		long start = System.currentTimeMillis();
		int result = 0;
		DomainMessage res1 = (DomainMessage) res.getBlockEventResult();
		if (res1.getBlockEventResult() != null)
			result = (Integer) res1.getBlockEventResult();

		long stop = System.currentTimeMillis();
		Assert.assertEquals(result, 400);
		System.out.print("\n ok \n" + result + (stop - start));
	} 
                            #location 10 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                             public static void main(String[] args) {
		AppUtil appUtil = new AppUtil();
		AService service = (AService) appUtil.getComponentInstance("aService");
		AggregateRootA aggregateRootA = service.getAggregateRootA("11");
		DomainMessage res = service.commandA("11", aggregateRootA, 100);

		long start = System.currentTimeMillis();
		int result = 0;
		DomainMessage res1 = (DomainMessage) res.getBlockEventResult();
		if (res1 != null && res1.getBlockEventResult() != null)
			result = (Integer) res1.getBlockEventResult();

		long stop = System.currentTimeMillis();
		Assert.assertEquals(result, 400);
		System.out.print("\n ok \n" + result + " time:" + (stop - start));
	}