#vulnerable code 
                             public static void main(String[] args) {
		Cache<Integer, Integer> cache = CacheBuilder.transactionalHeapCache()
				.transactionCommitter(new TransactionCommitter<Integer, Integer>() {
					int counter = 0;

					public void doPut(Integer key, Integer value) {
						if (counter < 3) {
							System.out.println("key[" + key + "]," + "value[" + value + "]");
							counter++;
						} else {
							throw new RuntimeException();
						}
					}
				}).build();
		Transaction transaction1 = CacheTransaction.get();
		transaction1.begin();
		try {
			cache.put(3, 5);
			cache.put(10, 14);
			transaction1.commit();
		} catch (TransactionException exception) {
			transaction1.rollback();
		} finally {
			transaction1.close();
		}
		System.out.println("Value for the key 3 is " + cache.get(3));
		System.out.println("Value for the key 10 is " + cache.get(10));
		Transaction transaction2 = CacheTransaction.get();
		transaction2.begin();
		try {
			cache.put(1, 10);
			cache.put(10, 13);
			transaction2.commit();
		} catch (TransactionException exception) {
			transaction2.rollback();
		} finally {
			transaction2.close();
		}
		System.out.println("Value for the key 1 is " + cache.get(1));
		System.out.println("Value for the key 10 is " + cache.get(10));
	} 
                            #location 29 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                             public static void main(String[] args) {
		example();
	}