'Java, How do I get current index/key in "for each" loop [duplicate]

In Java, How do I get the current index for the element in Java?

for (Element song: question){
    song.currentIndex();         //<<want the current index.
}

In PHP you could do this:

foreach ($arr as $index => $value) {
    echo "Key: $index; Value: $value";
}
java


Solution 1:[1]

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"

Solution 2:[2]

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.

Solution 3:[3]

Keep track of your index: That's how it is done in Java:

 int index = 0;
    for (Element song: question){
        // Do whatever
         index++;
    }

Solution 4:[4]

Not possible in Java.

Here's the Scala way:

val m = List(5, 4, 2, 89)

for((el, i) <- m.zipWithIndex)
  println(el +" "+ i)

Solution 5:[5]

As others pointed out, 'not possible directly'. I am guessing that you want some kind of index key for Song? Just create another field (a member variable) in Element. Increment it when you add Song to the collection.

Sources

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Source: Stack Overflow

Solution Source
Solution 1 Michael Mrozek
Solution 2 TheLQ
Solution 3
Solution 4 Maifee Ul Asad
Solution 5 likejudo

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