Required Help

[Remaan Rem]

Hi Everyone ,

Can anyone help me finding the bug in the following piece of code ?

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public DictEntry findNextEntry() {
		// TODO Auto-generated method stub
		 /* There is a critical side effect in this method! The private attribute currentIndex is left pointing at the currently found 
		 * dictionary entry.  This attribute is set to -1 when the search string is established.  If the value of it is -2, there is no 
		 * search string and so null is return.  If it is -1, there IS a search string, but it has not been used.  If it is zero or 
		 * more, it there is a search string and currentIndex points to the PREVIOUSLY FOUND dictionary entry.
		 */ 
		if (currentIndex < -1) return null;		// No search string, so just return now with a null result
		
		// Loop until the end of the dictionary is found (or the internal if statement terminates the loop by doing a return)
		while (currentIndex < numEntries-1) {
			// Fetch the NEXT entry by means of PRE-INCREMENTING the currentIndex
			
			DictEntry de  = listDictionary.get(++currentIndex);
			// See if that entry's word contains the search string; if so, return the entry to the caller
			if (de.getWord().indexOf(searchString)>=0)
				return de;
			// If not, the loop continues until the end of the sequence has been reached or a match was found just above
		}
		// If the CPIU gets here, it means that a search has failed to find a next entry, so we signal this by returning null and
		// setting the currentIndex to -2, forcing a new search string to be established before another search is possible.
		currentIndex = -2;		// No more items to search
		return null;			// This search did not succeed
	}

[Bear Bibeault]

I modified your subject a bit as a favor. Demanding immediate help is not only rude, it's counter-productive. Please read this: EaseUp.

Also, please read this: UseAMeaningfulSubjectLine. A better subject line will attract more volunteers who can help you.

[Janeice DelVecchio]

What is the code doing or not doing that isn't expected? Just saying that something doesn't work isn't really too descriptive.

Are you able to compile? Are you getting a runtime error? Is it working, but not as expected?

What kinds of error messages are you getting?

[Remaan Rem]

The method should find the nextentry of list, but it does not do so.

I couldn't really figure out why or how to fix that , when this is the only problem.

Remaan Rem

[Janeice DelVecchio]

If you're sure there's something in the list to get, it's probably something wrong with your loop logic.

You might want to seperate the incrementing of the currentIndex from the get() method for the list. In other words, increment at the very end, after everything else in that loop is done.

That may help narrow down the problem.

[Remaan Rem]

I am not sure I get what you mean ..

Do you mean I shall use a while loop, where the increamenting happens inside of the the loop rather than the header ?

What do you think ?

[Janeice DelVecchio]

Instead of this:

DictEntry de  = listDictionary.get(++currentIndex);      

Choose this:

DictEntry de  = listDictionary.get(currentIndex);
currentIndex++;      

The top one increments the variable before it's used, which can cause problems. By separating the usage and the increment, you may fix your issue.

[Remaan Rem]

Ya .. Bu even doing what you said changes the task alittle bit ..

We want to get the element at this index after increamenting it ..

What do you think >

[Janeice DelVecchio]

So you never touch the entry at the currentIndex?

[Remaan Rem]

It should look like that >

as this is a given piece of code ..

Anyways , I tried your suggestion , without a benefit.

And, eventually submitted the Assignment on that shape ..

Thanks alot for your help .. and have a nice day Janeice

Remaan