import java.util.StringTokenizer;public class StringTokenizerTest {    public static void main(String[] args)    {        String str="数学::英语::语文::化学";        StringTokenizer st=new StringTokenizer(str,"::");        System.out.println(st.countTokens());                while(st.hasMoreTokens())        {            System.out.println(st.nextToken());                    }    }}