Java, How do I get current index/key in "for each" loop

2018-06-18 19:04:03

This question already has an answer here:

Is there a way to access an iteration-counter in Java's for-each loop? 14 answers

You can't, you either need to keep the index separately:

int index = 0;
for(Element song : question) {
    System.out.println("Current index is: " + (index++));
}

or use a normal for loop:

for(int i = 0; i < question.length; i++) {
    System.out.println("Current index is: " + i);
}

The reason is you can use the condensed for syntax to loop over any Iterable, and it's not guaranteed that the values actually have an "index"

for (Song s: songList){
    System.out.println(s + "," + songList.indexOf(s); 
}

it is possible in linked list.

you have to make toString() in song class. if you don't it will print out reference of the song.

probably irrelevant for you by now. ^_^

In Java, you can't, as foreach was meant to hide the iterator. You must do the normal For loop in order to get the current iteration.

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