java.util.HashMap 클래스 – 예제

import java.util.*; 
public class HashMapTest { 
  public static void main(String args[]) { 
    Map map = new HashMap(); 
    Integer hana = new Integer(1); 
    for (int i=0, n = args.length; i<n; i++) { 
      String key = args[i]; 
      Integer freq = (Integer)map.get(key); 
      if (freq == null) { 
        freq = hana; 
      } 
    else { 
        int value = freq.intValue(); 
        freq = new Integer(value + 1); 
      } 
      map.put(key, freq); 
    } 
    System.out.println(map); 
    Map sortedMap = new TreeMap(map); 
    System.out.println(sortedMap); 
  } 
} 

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