Java/C2/User-Input/English-timed

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Time Narration
00:02 Welcome to the spoken-tutorial on taking User input in Java, using BufferedReader .
00:09 In this tutorial, we will learn:
00:11 To take user input in Java
00:13 About InputStreamReader and BufferedReader.
00:17 To follow this tutorial, you must know
00:19 how to write, compile and run a simple java program in Eclipse.
00:24 You must also know about the data types in Java.
00:27 If not, please refer to the spoken tutorial on these topics available at spoken hyphen tutorial dot org.
00:35 Here, I am using:

Ubuntu v 11.10 JDK 1.6 and Eclipse IDE 3.7.0

00:44 Now, we will learn what a BufferedReader is!
00:48 It is a class in java which is used to read text from an input stream.
00:53 It provides efficient way to read array of characters and lines.
00:59 To make use of BufferedReader , we need to import three classes from the java dot io package.
01:05 These three classes are:

IOException InputStreamReader and BufferedReader

01:12 We will learn about packages and how to import classes in the coming tutorials.
01:18 Now how is the input taken?
01:21 All the input that we take from the user will be in the form of string.
01:26 It has to be then typecasted or converted to the particular data type.
01:31 We will see that while we write our program to take the user input.
01:35 Now, let us see the syntax to implement BufferedReader.
01:39 Once you import the three classes, you need to create an object of InputStreamReader.
01:45 You also need to create an object of BufferedReader.
01:49 We will learn about this in detail when we write our program.
01:54 So, let us switch to Eclipse.
01:56 I have already opened a class named InputBufferedReader.
02:00 We will begin with importing the java.io package.
02:04 So, type: before the class, import space java dot io dot star semicolon.
02:13 This will import the classes InputStreamReader, BufferedReader and IOException.
02:20 Now, we will make use of BufferedReader inside the main method.
02:25 We need to throw an IOException in whatever method we use the BufferedReader.
02:31 So, right after the main method type: throws space IOException.
02:42 Now, what does this mean?
02:45 Exceptions are errors which occur in Java when some unexpected circumstances occur.
02:52 To prevent Exception errors we make use of throws keyword.
02:57 Throws is a keyword which is used during Exception handling.
03:00 It is used whenever we know that Exception error will definitely occur.
03:05 When we use BufferedReader, exception error always takes place.
03:10 To prevent Exception errors from taking place we make use of throws IOException.
03:16 We will learn about Exception Handling in the coming tutorials.
03:20 Now, we will create an object of InputStreamReader.
03:24 For that, inside the main method type: InputStreamReader space isr equalto new space InputStreamReader parentheses.
03:44 Within parentheses, type: System dot in and then semicolon.
03:52 InputStreamReader is a class in java which allows us to take the user input .
04:01 System dot in tells the java compiler to take the input from the user, using keyboard.
04:10 The input that System dot in takes is stored in the object of InputStreamReader for sometime.
04:17 After this we create an object of BufferedReader.
04:22 So, type: BufferedReader space br equal to new space BufferedReader and then parentheses.
04:36 Inside the parentheses, type the object of InputStreamReader which is isr.
04:43 Now, isr only helps to take the input from the user.
04:48 BufferedReader helps to store the value in the BufferedReader object.
04:54 Isr passes this value to the BufferedReader object to store it.
05:01 Now, let us start taking input from the user.
05:06 We will first ask the user to enter a String. So create a variable of String type.
05:14 Type: String space str semicolon.
05:19 Now ask the user to enter his name.
05:23 So, type: System dot out dot println within brackets and double quotes Enter your name and then semicolon.
05:33 To take the input as String we will type:
05:37 str equal to br dot readLine parentheses and then semicolon.
05:45 The readLine method will read the input from the user.
05:51 Now, let us take the input as an integer. Create a variable of type int.
06:01 So, type: int n semicolon.
06:05 Ask the user to enter his age.
06:08 So, type: System dot out dotprintln within brackets and double quotes Enter your age semicolon.
06:21 Also, create another variable named str1 of String type in order to take the input.
06:31 Now, to take the input as String, type: str1 equal to br dot readLine parentheses and then semicolon.
06:45 To convert it into integer datatype, type: n equal to Integer with capital I dot parseInt, capital I within brackets str1 semicolon.
07:05 Integer is a class and parseInt is its method.
07:11 This method converts the argument passed within the bracket into integer.
07:18 Now, let us display the output for name and age.
07:22 So, type: System dot out dot println within brackets and double quotes The name is plus str semicolon.
07:38 Next line, type: System dot out dot println The age is plus n and then semicolon.
07:50 Now, Save the file, press Ctrl, S keys. Now let us run the program.
07:55 So, press Control and F11 keys.
08:00 In the output, you are asked to enter your name.
08:03 So, type your name. I will type here Ramu, press Enter.
08:08 You will be asked to enter your age.
08:11 I will type here 20 and then press Enter.
08:13 We get the output as :
08:15 The name is Ramu And The age is 20.
08:18 Thus, we know how to take an input from the user.
08:24 In this tutorial we have learnt :
08:26 About InputStreamReader
08:28 About BufferedReader And Converting from String to the desired data type.
08:33 For self-assessment, take a float, byte and character input from the user and then display the output.
08:42 Also take a number as input and divide it by 3. Then display the output on the console.
08:49 To know more about the spoken tutorial project, watch the video available at the following link.
08:54 It summarizes the Spoken Tutorial project.
08:57 If you do not have good bandwidth, you can download and watch it.
09:02 The Spoken Tutorial project team:
09:04 Conducts workshops using spoken tutorials.
09:07 Gives certificates to those who pass an online test.
09:11 For more details, please write to contact@spoken-tutorial.org
09:18 Spoken Tutorial project is a part of the Talk to a Teacher project.
09:21 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
09:27 More information on this mission is available at:http://spoken-tutorial.org\NMEICT-Intro.
09:36 This is Arya Ratish from IIT Bombay.

Thank You for joining.

Contributors and Content Editors

Gaurav, PoojaMoolya, Sandhya.np14, Sneha