sortedmapdemo.java

Thinking in JAVA第四版源代码

//: containers/SortedMapDemo.java
// What you can do with a TreeMap.
import java.util.*;
import net.mindview.util.*;
import static net.mindview.util.Print.*;

public class SortedMapDemo {
  public static void main(String[] args) {
    TreeMap<Integer,String> sortedMap =
      new TreeMap<Integer,String>(new CountingMapData(10));
    print(sortedMap);
    Integer low = sortedMap.firstKey();
    Integer high = sortedMap.lastKey();
    print(low);
    print(high);
    Iterator<Integer> it = sortedMap.keySet().iterator();
    for(int i = 0; i <= 6; i++) {
      if(i == 3) low = it.next();
      if(i == 6) high = it.next();
      else it.next();
    }
    print(low);
    print(high);
    print(sortedMap.subMap(low, high));
    print(sortedMap.headMap(high));
    print(sortedMap.tailMap(low));
  }
} /* Output:
{0=A0, 1=B0, 2=C0, 3=D0, 4=E0, 5=F0, 6=G0, 7=H0, 8=I0, 9=J0}
0
9
3
7
{3=D0, 4=E0, 5=F0, 6=G0}
{0=A0, 1=B0, 2=C0, 3=D0, 4=E0, 5=F0, 6=G0}
{3=D0, 4=E0, 5=F0, 6=G0, 7=H0, 8=I0, 9=J0}
*///:~