Creating a Hash Table : Map « Collections Data Structure « Java






  1. Java
  2. Collections Data Structure
  3. Map

Creating a Hash Table

import java.util.HashMap; import java.util.Iterator; import java.util.Map; import java.util.TreeMap; publicclass Main { publicstaticvoid main(String[] argv) throws Exception { Map<String, Integer> map = new HashMap<String, Integer>(); map = new TreeMap(); map.put("a", newInteger(1)); map.put("b", newInteger(2)); map.put("c", newInteger(3)); int size = map.size(); // 2  Object oldValue = map.put("a", newInteger(9)); // 1  oldValue = map.remove("c"); // 3  Iterator it = map.keySet().iterator(); while (it.hasNext()) { Object key = it.next(); } it = map.values().iterator(); while (it.hasNext()) { Object value = it.next(); } } }








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