I have a String 2D-array named items in my app like this :
String[][] items = { {"(kilogram)","1"}, {"(gram)","1000"}, {"(pound)","2.20462262"}, {"(pound - troy)","2.6792288807"}, {"(carat)","5000"}, {"(ounce)","35.2739619"}, {"(ounce - troy)","32.1507466"}, }
and I want to have a String ArrayList that include first parameter of each item data, something like this :
ArrayList<String> data = new ArrayList<>(); data = {(kilogram),(gram),(pound),(pound - troy),(carat),(ounce),(ounce - troy)}
i used this code but unfortunately it didn’t work
ArrayList<String> data = new ArrayList<>(); for (int i = 0; i <= items.length;) { data.add(items[i][0]); i++; }
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Answer
You can also use streams to build this list:
List<String> data = Stream.of(items) .map(item -> item[0]) .collect(Collectors.toList());
If you still want to use a for loop go with (use <
instead of <=
):
for (int i = 0; i < items.length; i++) { data.add(items[i][0]); }