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Java Java Objects Meet Objects Welcome Back

Posted by oussama zeglama
oussama zeglama
Courses Plus Student 340 Points

I don't know when to put the " " ? For example int age = Integer.parseInt("30"); int age = Integer.parseInt(AGE);

NEED HELP ?

2 Answers

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

It looks like you have it correct in your examples.

Quotes go around a literal string (like "30") but never around a variable name (AGE).

oussama zeglama
oussama zeglama
Courses Plus Student 340 Points

you mean by literal string just numbers ?

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

A literal string can have anything ("Bob", "robots", "this is a test", etc.). But one that you might give to "parseInt" would just have numbers.

oussama zeglama
oussama zeglama
Courses Plus Student 340 Points

So what s the difference between the variable name and the literal string ?

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

The variable name represents the value that was previously assigned to it.
A literal string only represents what is contained in the quotes.

Mike Meany
Mike Meany
3,988 Points
Mike Meany
Mike Meany
3,988 Points

To reiterate what Steven said, a String will always have quotes around it, variables wont. To expand a bit; ints will always be numbers but never have quotes, strings can be/contain letters, symbols or numbers and will always have quotes. Lets take the example of;

int x = 1; int y = 2; System.out.println(x + y);

This will output 3 as it adds the two numbers together

now take this example

String x = "1"; String y = "2";

System.out.println(x + y);

This will output 12 as it concatenates the two strings together

If you wanted to add the two numbers together from example 2 then you would have to parse them and it would look something like this;

System.out.println(Integer.parseInt(x) + Integer.parseInt(y));

or

System.out.println(Integer.parseInt("1") + Integer.parseInt("2"));