String operation in Java -

is code correct? have mentioned doubts in form of comments in places:

public class pract1 {     public static void main (string[] args)     {         int i;         string [] array = new string[20]; // declaration correct?         bufferedreader br = new bufferedreader(new inputstreamreader(system.in));         system.out.println("enter array: ");         array = br.readline(); // correct way accept input keyboard?         i=0;         while(array[i]!='\0') // can use null pointer concept in java?         {             system.out.println("the "+(i+1)+"character is:" +array[i]+"\n"); //want print each , every characters in string along position             i++;         }        } } 

this how it:

import java.io.bufferedreader; import java.io.inputstreamreader;  public class pract1 {     public static void main (string[] args)     {         string array = ""; //initialize empty string hold value keyboard         bufferedreader br = new bufferedreader(new inputstreamreader(system.in)); // initialize bufferedreader          // while "stop" not typed on console, keep running         while(!array.equals("stop")) {             system.out.println("enter array: ");             try {                 array = br.readline(); // read console                 system.out.println("array:" + array);                 for(int i=0; i<array.length(); i++) { //loop through input , show chars                     system.out.println("character "+(i+1)+" is: " +array.charat(i));                 }              } catch (exception e) { // catch exception , show message, not entire stacktrace                 system.out.println("error: " +  e.getmessage());             }             system.out.println("");         }      } }