Get index of contain sublist from list java

Question

I have string lists look like this:

 List parentDataList:  {\"this\", \"is\", \"a\", \"test\", \"string\", \"and\", \"a\", \"test\", \"other\"}         


        

Answer 1

If you want to do it manually :

public static List<Interval> getIntervals2(String[] parent, String[] child) {
    List<Interval> intervals = new ArrayList<Launch.Interval>();

    for (int i = 0; i < parent.length; i++) {
        if (child[0].equals(parent[i])) {
            Interval interval = new Interval();
            interval.start = i;
            intervals.add(interval);
        }
    }

    ListIterator<Interval> iterator = intervals.listIterator();
    while (iterator.hasNext()) {
        Interval interval = iterator.next();
        for (int j = 1, i = interval.start + 1; i < child.length; i++, j++) {
            if (!child[j].equals(parent[i]))
                iterator.remove();
        }
        if (interval.start + child.length - 1 < parent.length - 1)
            interval.end = interval.start + child.length - 1;
        else
            iterator.remove();
    }

    return intervals;
}

Answer 2

The method Collections.indexOfSubList will give you the desired information.

Returns the starting position of the first occurrence of the specified target list within the specified source list, or -1 if there is no such occurrence. More formally, returns the lowest index i such that source.subList(i, i+target.size()).equals(target), or -1 if there is no such index. (Returns -1 if target.size() > source.size().)

int index=Collections.indexOfSubList(parentDataList, child1);
…

The index interval will be from index, inclusive, to index+child1.size(), exclusive. Unless the returned index is -1, of course. In the latter case the sublist was not found.

Answer 3

You can change @Alessio's code like this. It also works on your cases.

public List<Interval> getIntervals(String[] parent, String[] child) {
    List<Interval> intervals = new ArrayList<Interval>();
    Interval interval = new Interval();

    for (int i = 0, j = 0; i < parent.length; i++) {
        if (child[j].equals(parent[i])) {
            j++;
            if (j == 1) {
                interval.start = i;
            }
            if (j == child.length) {
                interval.end = i;
                intervals.add(interval);
                interval = new Interval();
                j = 0;
            }
        } else {
            j = 0;
        }
    }

    return intervals;
}