Java programming- DO NOT USE BREAK METHOD Goals The lab this lesson introduces s

Question

Java programming- DO NOT USE BREAK METHOD

Goals

The lab this lesson introduces students to File I/O and exception processing. By the end of this lab, students should be able to

Read and write text files

Process input from a file

Read web pages

Catch exceptions

Question-

Write a program to query

http://www.oracle.com/technetwork/java/javase/downloads/index.html

and display the first release number for a JDK listed on that page (and ONLY the release number). For example, at the time of this writing, the output would be

8u101

This summer (when our virtual machines were created), the release number output would have been

8u91

Your program should handle any thrown exceptions with an informative message.

Explanation / Answer

Hi,
Please see the below classes. Please comment for any queris/feedbacks.
Thanks.

WebpageReader.java

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.Scanner;
import java.util.StringTokenizer;

public class WebpageReader {
   public static void main(String [] args){
       try {
           //Connecting to the URL
           URL url = new URL("http://www.oracle.com/technetwork/java/javase/downloads/index.html");
           // Read all the text returned by the server
           BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));
           String str;
           String relaeseNumber ="";
           while ((str = in.readLine()) != null) {
               //Reading each string on a line
               StringTokenizer token = new StringTokenizer(str);
               while(token.hasMoreElements()){
                   relaeseNumber= token.nextToken();
                   //Checking each word, if it starts with '8u' and '8u' should be starting
                   //and length should be less than 10
                   if(relaeseNumber.contains("8u") && relaeseNumber.indexOf("8u") ==0
                           && relaeseNumber.length()<10){
                       //Removing html tags from the releaaseNumber
                       int trailIndex = relaeseNumber.indexOf("<");
                       String trail = relaeseNumber.substring(trailIndex);
                       relaeseNumber = relaeseNumber.replace(trail, "");
                       System.out.println("Release number for a JDK :: "+relaeseNumber);
                   }
               }
           }
           in.close();
       }
       catch(IOException ex) {
           // there was some connection problem, or the file did not exist on the server,
           // or your URL was not in the right format.
           // think about what to do now, and put it here.
           ex.printStackTrace(); // for now, simply output it.
       }
   }

}

Sample output:

Release number for a JDK :: 8u131

Related Questions

Navigate

• Browse (All)
• Browse J
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.