JAVA Linked List How to loop through with a for loop?
Hello I am trying to create a for loop that loops through the linked list. For each piece of data it will list it out individually. I am trying to learn linked list here, so no Array suggestions please. Anyone know how to do this?
Example开发者_JAVA百科 Output:
- Flight 187
- Flight 501
CODE I HAVE SO FAR BELOW:
public static LinkedList<String> Flights = new LinkedList<String>();
public flightinfo(){
String[] flightNum = {"187", "501"};
for (String x : flightNum)
Flights.add(x);
for (???)
}
Just use the enhanced for-loop, the same way you'd do it with an array:
for(String flight : flights) {
// do what you like with it
}
If I understand you correctly, you have to get a reference to the List's iterator and use that to cycle through the data:
ListIterator iterator = Flights.iterator();
while (iterator.hasNext()){
System.out.print(iterator.next()+" ");
}
for(String y : Flights) {
//...
}
The same way as arrays, since it inherits from Iterable<T>
As pointed out by @Cold Hawaiian this only works for Java >= 5.0
If pre 5.0 use:
ListIterator<String> iter = Flights.iterator();
while(iter.hasNext()) {
String next = iter.next();
// use next
}
You should use a ListIterator (see Java API for more information).
If you have distinct values in the linked list , this would work :
for(Iterator<String> i = Flights.listIterator(); i.hasNext();){
String temp = i.next();
System.out.println(Flights.indexOf(temp)+1+". Flight "+temp );
}
If you do not have distinct values in the linked list, this would work :
int i=0;
for(Iterator<String> iter = Flights.listIterator(); iter.hasNext();i++){
String temp = iter.next();
System.out.println(i+1+". Flight "+temp );
}
Hope this helps.
With Java8 Collection classes that implement Iterable have a forEach() method. With forEach() and lambda expressions you can easily iterate over LinkedList
flights.forEach(flight -> System.out.println(flight));
while(!flights.isEmptry) {
System.out.println(flights.removeFirst());
}
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