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From these data structures, I want to remove elements by value, that satisfies certain condition

<Data Structures>

 - RowSortedTable<String, String, Double> a;     (Guava Table)
 - HashMap<String, Double> b;

From the previous question, I found the elegant answer using Collections.Singleton however, it seems like exact matching is required.

hmap.values().removeAll(Collections.singleton("Two"));

Here, I want to remove elements from a table or map where their values are smaller than certain threshold. What would be your way to write the code?

I just checked two answers and those are answers about map, how about the table case? My solution is as follows.

for (Iterator<String> it1 = proptypeconf.columnKeySet().iterator(); it1.hasNext();) {
        String type = it1.next();
        System.out.println(type);
        for (Iterator<Map.Entry<String, Double>> it2 = proptypeconf.column(type).entrySet().iterator(); it2.hasNext();){
            Map.Entry<String, Double> e = it2.next();
            if (e.getValue() < conflist.get(index-1)) {
                it2.remove();
            }
        }
    }
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SUNDONG
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  • `Table` is no different at all. Just use `table.values()` the same as for maps. You can use exactly the same code. – Louis Wasserman Oct 14 '15 at 20:17
  • @LouisWasserman Thank you! Just checked out tables work exactly the same. I was trying to solve a problem the hard way ... :( – SUNDONG Oct 14 '15 at 20:24

1 Answers1

13
Iterator<Integer> iterator = hmap.values().iterator();
while (iterator.hasNext()) {
  if (iterator.next() < threshold) {
     iterator.remove();
  }
}

Of course, if you're on Java 8, it's much easier:

hmap.values().removeIf(value -> value < threshold);

Tables work exactly the same; just use table.values() instead of hmap.values().

Louis Wasserman
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