Java Programs Made Easy

Q)..A time input is received as stirng. Find if the hour format is in 12 hour format. the suffix am/pm is case insensitive.
input:"09:36 am"
output:true

1. package Set1;
2. import java.text.*;
3. import java.util.*;
4. public class ClassSet12 {
5.  public static boolean hourFormat(String s) throws ParseException{
6.   boolean b=false;
7.   StringTokenizer st=new StringTokenizer(s," ");
8.   String s1=st.nextToken();
9.   String s2=st.nextToken();  
10.   StringTokenizer st1=new StringTokenizer(s1,":");
11.   int n1=Integer.parseInt(st1.nextToken()); 
12.   int n2=Integer.parseInt(st1.nextToken()); 
13.   if((s2.equalsIgnoreCase("am"))|| (s2.equalsIgnoreCase("pm")))
14.    if((n1<=12)&&(n2<=59))
15.     b=true; 
16.   return b;
17.  }
18.  public static void main(String[] args) throws ParseException {
19.   String s="19:36 am";
20.   boolean b=hourFormat(s);
21.   if(b==true)
22.    System.out.println("the time is in 12 hr format");
23.   else
24.    System.out.println("the time is in 24 hr format");
25.  }
26. }