1. The String type

The String type is one of the most used types in Java. It just might be the most used type. There's a reason why it is so popular: such variables let you store text — and who doesn't want to do that? Additionally, unlike the int and double types, you can call methods on objects of the String type, and these methods do some useful and interesting things.

What's more, all Java objects (all of them!) can be transformed into a String. Well, to be more precise, all Java objects can return a text (string) representation of themselves. The name of the String type starts with a capital letter, because it is a full-fledged class.

We'll return to this type more than once (it is super useful and interesting), but today we will make a brief introduction.

2. Creating String variables

The String type is designed for storing strings (text). To create a variable in code that can store text, you need to use a statement like this:

String name;
Creating a String variable

Where name is the name of the variable.


Statement Description
String name;
A string variable named name is created
String message;
A string variable named message is created
String text;
A string variable named text is created

Just as with the int and double types, you can use the shorthand notation to create multiple String variables:

String name1, name2, name3;
Shorthand for creating multiple String variables

3. Assigning values to String variables

To put a value into a String variable, you need to this statement:

name = "value";
Assigning a value to a String variable

And now we have come upon the first difference between this type and those we have already studied. All values of the String type are strings of text and must be enclosed in double quotes.


Statement Note
String name = "Steve";
The name variable contains the text Steve
String city = "New York";
The city variable contains the text New York
String message = "Hello!";
The message variable contains the text Hello!

4. Initializing String variables

As with the int and double types, variables of the String type can be initialized immediately when they are created. In fact, this is something you can do with all types in Java. So we won't mention it anymore.

String name1 = "value1", name2 = "value2", name3 = "value3";
Shorthand for creating and initializing variables
String name = "Steve", city = "New York", message = "Hello!";
Example of a statement that creates and initializes variables
Please note:

The Java compiler will complain if you declare a variable without assigning any value to it and then try to use it.

This code won't work:

Statement Note
String name;
The name variable is not initialized. The program won't compile.
int a;
The a variable is not initialized. The program won't compile.
double x;
double y = x;
The x variable is not initialized. The program won't compile.

New Java Syntax,  level 2lesson 3
We solemnly publish and declare these variables...
Declare int variables called a and b. In the same line in which the variables are declared, immediately assign them different values. The values can be any integers.