只需为Java中的Integer.valueOf（）编写Junit

Question

So here is the thing, I found new Integer() in my code and which is deprecated now I planed to remove that pic of code (new Integer()) to Integer.valueOf() but as company rules I have to write the Junit for that change, I just need to verify that pic of code no need to write whole coverage of the method, Now I am getting confused, how I can do it.

Before:

@SuppressWarnings({ "rawtypes", "unchecked" })
    public List getLogsByLcrErrorCodeInLast(String code, long period) throws Exception {
        Object params = new ObjectPair(new Integer(code), new MesDbUtil(ibatis).getPastMesDbDate(period));
        List mesdbLogs = client.queryForList("LcrLog.getLogsByLcrErrorCodeInLast", params);
        Iterator mesdbLogsIter = mesdbLogs.iterator();
        List results = new ArrayList();
        while (mesdbLogsIter.hasNext()) {
            MesDbLcrLog mesdbLog = (MesDbLcrLog) mesdbLogsIter.next();
            results.add(mesdbLog.getLog());
        }
        return results;
    }

After::

@SuppressWarnings({ "rawtypes", "unchecked" })
    public List getLogsByLcrErrorCodeInLast(String code, long period) throws Exception {
        Object params = new ObjectPair(Integer.valueOf(code), new MesDbUtil(ibatis).getPastMesDbDate(period));
        List mesdbLogs = client.queryForList("LcrLog.getLogsByLcrErrorCodeInLast", params);
        Iterator mesdbLogsIter = mesdbLogs.iterator();
        List results = new ArrayList();
        while (mesdbLogsIter.hasNext()) {
            MesDbLcrLog mesdbLog = (MesDbLcrLog) mesdbLogsIter.next();
            results.add(mesdbLog.getLog());
        }
        return results;
    }

I tried to do like following, I don't know is it correct or not, and need to go for some professional way for it too because of code review;

public class integerValueOf(){
    private Integer code=23;
    @Test
        public void testGetLogsByLcrErrorCodeInlast() throws Exception{
            assertEquals(new Integer(code), Integer.valueOf(code));
        }
    }

Answer 1

Are you unit testing every other API in the JRE? No? Why would you unit test Integer.valueOf(...) then?

Your existing unit tests for getLogsByLcrErrorCodeInLast should cover the change in the integer instantiation. Eg you have tests for different values of code and check that you get the expected params in client.queryForList(...) .

If you don't have the tests, then you need to write them before you change the code.

Edit: I didn't even notice it earlier, but your production code converts a String to an Integer and your sugested unit test converts an Integer to an Integer. You're idea is fundamentally flawed because it doesn't test the code that you execute in production. It lets errors like this pass testing with green flags.