You can check two strings to see if they are the same. For this, use the equals
method in Java. Here's some code:
In this code, we want to check if one email address is the same as another.
The first two lines set up two string variables, one for each email address.
The third line sets up a Boolean variable. That's because the equals method
returns a value of true or false. The fourth line is where we use the method:
The equals method only compares objects, however. It's OK for strings, because they are objects. But you can't use the equals method to compare int variables. For example, this code would get you an error:
Another useful Java string method is charAt. You'll meet this in the next lesson.

isMatch = email_address1.equals( email_address2 );
In between the round brackets of the equals method, you place the string
you're trying to check. The other string goes before the equals method. Java
will then tell you (true or false) whether the two are the same. The IF statement
checks which one it is.The equals method only compares objects, however. It's OK for strings, because they are objects. But you can't use the equals method to compare int variables. For example, this code would get you an error:
int num1 = 12;
int num2 = 13
Boolean isMatch = false;
int num2 = 13
Boolean isMatch = false;
isMatch = num1.equals(num2);
The int variable is a primitive data type, and not an object. You can turn
the primitive int data type into an object, though:
int num1 = 12;
Integer num_1 = new Integer(num1);
Here, the int variable called num1 is being turned into an Integer object.
Note the use of the new keyword. In between the round brackets of Integer, you
put the primitive int data type you want to convert to an object.Integer num_1 = new Integer(num1);
Another useful Java string method is charAt. You'll meet this in the next lesson.
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