java TreeMap使用示例，javatreemap示例,package cn.o

java TreeMap使用示例，javatreemap示例,package cn.o

package cn.outofmemory.snippets.core;import java.util.TreeMap;public class SizeTreeMap {  public static void main(String[] args) {    // Create a TreeMap and populate it with elements    TreeMap treeMap = new TreeMap();    treeMap.put("key_1","element_1");    treeMap.put("key_3","element_3");    treeMap.put("key_2","element_2");    treeMap.put("key_4","element_4");    treeMap.put("key_5","element_5");    // int size() operation returns the number of key value pairs stored in TreeMap        System.out.println("Size of TreeMap : " + treeMap.size());  }}

输出：

Size of TreeMap : 5