Reverse a string(JAVA)

import java.io.*;
class node
{
node top;
node next;
char name;
node()
{}
node(char c)
{
name=c;
}
}
class link extends node
{
void push(char c)
{
node newnode=new node(c);
if(top==null)
{
top=newnode;
}
else
{
newnode.next=top;
top=newnode;
}
}
char pop()
{
node pot=top;
top=top.next;
return(pot.name);
}
}
class reverse
{
public static void main(String args[])
{
try
{
link k=new link();
char ch;
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("enter the string");
String s=br.readLine();
int l=s.length();
for(int i=0;i<l;i++)
{
char c=s.charAt(i);
k.push(c);
}
System.out.println("the reverse is   ");
for(int i=0;i<l;i++)
{
System.out.print(k.pop());
}
}catch(IOException e)
{
System.out.println(e);
}
}
}