Java/C2/Strings/English

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Title of script: Strings in Java

Author: TalentSprint

Keywords: datatype, char, strings, adding strings, video tutorial

Visual Cue Description
Slide 1

Welcome

Welcome to the spoken tutorial onStrings in Java.
Slide 2

Learning Outcomes

In this tutorial, you will learn how to

create strings,add strings and perform basic string operations like converting to lower case and upper case.

Slide 3

Tools Used

For this tutorial we are using

Ubuntu 11.10, JDK 1.6 and

Eclipse 3.7'

Slide 4

Prerequisites

To follow this tutorial you must have knowledge ofdata types in Java.

If not, for relevant tutorial please visit our website as shown

Slide 5

Strings

String in Java, is a sequence of characters.

Before starting with Strings, we will first see the character data type.

Let us now switch to eclipse

Minimize Slides and open Eclipse

Eclipse should contain the following code

public class StringDemo{

public static void main(String[] args){

}

}

we have the eclipse IDE and the skeleton required for the rest of the code.

We have created a class StringDemo and added the main method.

Inside the main method, type

char star = '*';

Inside themain method, typechar star equal to in singlequotes asrteicks star

This statement creates a variable with name star and of the typechar.

It can store exactly one character.

Let us print a word using a few characters.

Type after thechar...

char c1 = 'c';

char c2 = 'a';

char c3 = 'r';

Remove the char line and type ,

'char c1equal to c'

'char c2equal to a'

'char c3 equal tor'

We have created three characters to make the wordcar.

Now let us use them to print the word.

Type afterchar3...

System.out.print(c1);

System.out.print(c2);

System.out.print(c3);

Save and Run.

Point to output

type,

System.out.print(c1);

System.out.print(c2);

System.out.print(c3);

Please note that I’m usingprint instead ofprintln so that all the characters are printed on the same line.

save the file and run it.

As we can see, the output is as expected.

But this method only prints the word but does not create one.

To create a word, we use theString data type.

Let us try it out.

Remove everything inside themain function and type

String greet = “Hello Learner”;

remove everything inside the main method and type

Type' String greet'equal to Hello Learnerin quotes;

Note that the S in the data typeString is in uppercase.

We have use double quotes instead of single quotes as delimiters

This statement creates a variablegreet that is of the typeString

Now Let us print the message.

Type the following

System.out.println(greet);

Save the file run it .

Point to output

System.out.println(greet);

Save the file and run it As we can see, the message has been stored in the variable and it has been printed.

Strings can also be added in Java.

let us see how to do so.

Change“Hello Learner” to“Hello“ I'm removing theLearner from the message.

We'll store the name in a different variable.

Type after thegreet... line

String name = “Java”;

String msg = greet + name;

changeprintln(greet) toprintln(msg)

Save and Run.

Point to output

'String name'equal to “Java”;

Now we’ll add the strings to make a message

'String msg'equal to'greet'plus name;

changeprintln(greet) toprintln(msg) save the file and run it.

We can see that the output shows the greeting and the name.

But there is no space separating them.

BeforeString greet line, type this

char SPACE = ' ';

Changegreet + name togreet + SPACE + name

Save and Run.

Point to output

so Let us create a space character;

char SPACE 'equal to ';

Note that I have used all uppercase letters in the variable name so that it is clear.

You can change it as you want.

Now let us add the space to the message.

'greet'plus'SPACE'plus name

save the file and run it

Now we can see the output is clear and as expected.

Let us look at a few basic string operations.

Change“hello” to“HeLLo”

Change“Java” to“jAvA”

Save and Run.

Point to output

I’m changing a few characters of “Hello” to upper case

and a word “java” to uppercase.

Often, when users give input, we have values like this, in mixed case.

So Let us run the file to see the output.

As we can see t he output is not clean.

Let us use the String methods to clean the input.

Add the following code beforeSystem...

greet = greet.toLowerCase();

name = name.toUpperCase();

Save and Run.

Point to output

type,

'greet'equal to greet.toLowerCase();

This statement converts each character of the stringgreet to lowercase

'name 'equal to name.toUpperCase();

This statement converts each character of the string name to uppercase.

Save the file and Run  it.

As we can see, the output is now clean after we have used the String methods.

This is how we create strings and perform string operations.

There are many more String methods and

We'll discuss them as we move on to complex topics.

Minimize theEclipse window and switch to slides.

Slide 6

Summary

This brings us to the end of this tutorial.

In this tutorial we have learnt

- how to create strings and addstrings

- few string operations like converting to lower case and upper case

Slide 7Assignment As a assignment,

- Read about theconcat method of Strings in Java. - Find out how is it different from adding strings.

Slide 8About the Spoken Tutorial Project To know more about theSpoken Tutorial project, watch the video available at the following link.

It summarises the Spoken Tutorial Project.

If you do not have good bandwidth, you can download and watch it

Slide 9Spoken Tutorial WorkshopsThe Spoken Tutorial Project Team
  • Conducts workshops using spoken tutorials
    • Gives certificates for those who pass an online test
      • org (contact at spoken-tutorial dot org)
The Spoken Tutorial Project Team.

Conducts workshops usingspoken tutorials.

Gives certificates for those who pass an online test. For more details, please write tocontact AT spoken HYPHEN tutorial DOT org.

Slide 10Acknowledgement
  • Spoken Tutorial Project is a part of the Talk to a Teacher project
Spoken Tutorial Project is a part of theTalk to a Teacher project and is supported by the National Mission on Education through ICT, MHRD, Government of India. More information on this Mission is available atspoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro
Slide 11About the contributor
  • This tutorial has been contributed byTalentSprint
  • www.talentsprint.com
    • Thanks for joining
This tutorial has been contributed byTalentSprint. Thanks for joining.

Contributors and Content Editors

Ashwini, Chandrika, Sneha