Java by API/java.io/BufferedReader

BufferedReader: readLine()

   <source lang="java">

/*

* Output:
*/

import java.io.BufferedReader; import java.io.FileReader; public class MainClass {

 public static void main(String args[]) {
   try {
     FileReader fr = new FileReader(args[0]);
     BufferedReader br = new BufferedReader(fr);
     String s;
     while((s = br.readLine()) != null)
       System.out.println(s);
     fr.close();
   }
   catch(Exception e) {
     System.out.println("Exception: " + e);
   }
 }

}

 </source>
   
  
 
  

new BufferedReader(FileReader fileReader)

   <source lang="java">

/*

* Output:
*/

import java.io.BufferedReader; import java.io.FileReader; public class MainClass {

 public static void main(String args[]) {
   try {
     FileReader fr = new FileReader(args[0]);
     BufferedReader br = new BufferedReader(fr);
     String s;
     while((s = br.readLine()) != null)
       System.out.println(s);
     fr.close();
   }
   catch(Exception e) {
     System.out.println("Exception: " + e);
   }
 }

}

 </source>
   
  
 
  

new BufferedReader(InputStreamReader input)

   <source lang="java">

/*

* Output:
*/

import java.io.BufferedReader; import java.io.InputStreamReader; public class MainClass {

 public static void main(String args[]) {
   try {
     InputStreamReader isr = new InputStreamReader(System.in);
     BufferedReader br = new BufferedReader(isr);
     while (true) {
       System.out.print("Radius? ");
       String str = br.readLine();
       double radius;
       try {
         radius = Double.valueOf(str).doubleValue();
       } catch (NumberFormatException nfe) {
         System.out.println("Incorrect format!");
         continue;
       }
       if (radius <= 0) {
         System.out.println("Radius must be positive!");
         continue;
       }
       double area = Math.PI * radius * radius;
       System.out.println("Area is " + area);
       return;
     }
   } catch (Exception e) {
     e.printStackTrace();
   }
 }

}

 </source>
   
  
 
  

new BufferedReader(Reader in)

   <source lang="java">

import java.io.BufferedReader; import java.io.InputStreamReader; import java.net.URL; public class Main {

 public static void main(String[] args) throws Exception {
   URL url = new URL("http://localhost:1776");
   BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));
   String line;
   while ((line = in.readLine()) != null) {
     System.out.println(line);
   }
   in.close();
 }

}

 </source>