一道很基础的题~~请说清楚原因!感谢!

/*
 *联系第二题
 *
 **/
import java.util.LinkedList;
import java.util.Iterator;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Random;class Test2
{        public static void print(Collection c) 
        {
                Iterator it = c.iterator();
                while(it.hasNext()) 
                {
                        System.out.println(it.next());
                }
                System.out.println();
        }
        
        public static void Seath(LinkedList tt,String a)
        {
         for(int i=0;i<=tt.size();i++)
          { 
           if(tt.get(i).toString().startsWith(a));
           System.out.println(tt.get(i));
           }
           
        }
        public static void main( String[] args ) throws Exception
         {
                Test2 test = new Test2();
                 LinkedList tt = new LinkedList();
                
               tt.add( "John Alex" );
               tt.add( "Miller Scott" );
               tt.add( "John Anna" );
               tt.add( "Johnson Jack" );
               tt.add( "Hunter Jeff" );
               tt.add( "Williams Serena" );
               tt.add( "Williams Uenus" );
                
                System.out.println( "  --------------------------------" );
                System.out.println( "  检索 LinkedList 中的对象" );
                System.out.println( "  --------------------------------" );
                print(tt);
                
                System.out.println( "--------------------------------" );
                System.out.println( "检索 LinkedList 中的指定对象" );
                System.out.println( "--------------------------------" );
                
              try{
           
                Seath(tt,"John");
                
                }
                catch(Exception e)
                {}
              
                        }
}
请问为啥检索不了"John"  
  请说清楚原因~~