I apologize for the basic question but my newness to Java is causing me some frustration and I am unable to find an elegant way to do this from my searches.
I want to iterate through a linked list using a For construct but also have an numerical iterator so that I can break the loop after a certain number of iterations.
I have this LL that I am iterating through:
LinkedList<SearchResult> docSearch开发者_如何学编程;
I tried doing it like this but then only the iterator part worked (the result was always stuck on the first entry for each iteration)
for (SearchResult result : docSearch) while (iter2 < 50) {
//do stuff
iter2 = iter2 + 1;
}
Any advice is appreciated
If you have to do that sort of checking, then I would just do it with an if in the block.
for (SearchResult result : docSearch) {
if (iter2 >= 50) break;
//do stuff
iter2 += 1;
}
It will be better to use regular for..loop syntax to handle your need
for (int i = 0; i < 50 && i < docSearch.getSize(); i++ ) {
SearchResult result = docSearch.get(i);
}
Just because Java support for-each loop, does not mean we have to use it every time. I find using regular for..loop syntax is easier to read where your condition is isolated in 1 place. If you use for-each with break then you have 2 places which affect your code flow.
where did you assign the value of iter2?
try
for (SearchResult result : docSearch)
{
int iter2 = 0;
while (iter2 < 50) {
//do stuff
iter2 = iter2 + 1;
}
}
for (SearchResult result : docSearch) {
if (iter2++ >= 50) break;
//do stuff
}
Here might be a nice place for a post-incrementation too. :)
If you do this:
for (SearchResult result : docSearch) while (iter2 < 50) {
//do stuff
iter2 = iter2 + 1;
}
It's the exact same as doing this:
for (SearchResult result : docSearch) {
while (iter2 < 50) {
//do stuff
iter2 = iter2 + 1;
}
}
You can get around this in a number of ways. One is a break (although some frown upon this as spaghetti code.
for (SearchResult result : docSearch) {
if(iter2 >= 50) break;
//do stuff
iter2 = iter2 + 1;
}
You can use a standard for loop and put the two conditions into the condition section
Iterator<SearchResult> iter = docSearch.iterator();
for(SearchResult result = iter.next(); iter.hasNext() && iter2 < 50; result = iter.next()) {
// do stuff
iter2 = iter2 + 1;
}
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