In this, part two of this ten part series on Java, Chris looks at the Java language syntax, variable declerations, truth conditions, loops and more. He finishes by wrapping everything up into a simple Java function.
Java Part 2: Syntax - Truth operations (Page 4 of 8 )
Truth is represented in Java as a boolean type, which is either true or false. The truth operators are as follows:
Equals ==
statement 1 == statement 2
Statements must be equal for the entire statement to be true.
And &&
statement 1 && statement 2
Both statements must be true for the entire statement to be true.
Or ||
statement 1 || statement 2
One or both of the statements must be true for the entire statement to be true.
Not !
!statement 1
True if the statement evaluates to false, and vice-versa.
Greater than and less Than < >
statement 1 < statement 2
OR
statement 1 > statement 2
Firstly, the result will be true if statement 1 is less than statement 2. Secondly, the result will be true if statement 1 is greater than statement 2.
If, Then, Else
The if, then, else construct is a powerful Java conditional statement for decision making in your code. It works as follows:
if ( some truth statement )
{
// perform task
}
else if( some other truth statement)
{
// perform task
}
else
{
// all other cases
}
Always enclose the conditional expressions in braces, as shown. This is not always essential but helps with readability. Also, indent the task performed by each condition by one tab space to enhance the readability of the code.