How to implement relational and logical operators in JShell in Java 9?

JShell has introduced in Java 9 that enables us to explore, discover, and experiment with Java language features, and extensive libraries.

The relational operators (==, != <, >, <=, >=) can be used mainly for comparison. It accepts operands of non-boolean primitive data types and returns a boolean value. JShell also supports logical operators that can be used in expressions. The logical operators can expect boolean operands. The expressions involving these operands can be used for forming boolean conditions in the code within if, for, and while statements. The logical operators include : "&& : logical AND", "|| : OR" and "! : NOT".

In the below two code snippets, we can implement relational operators using JShell.

Snippet-1

jshell> int i = 10;
i ==> 10

jshell> i > 10;
$2 ==> false

jshell> i >= 10;
$3 ==> true

jshell> i < 10;
$4 ==> false

jshell> i <= 10;
$5 ==> true

jshell> i == 10;
$6 ==> true

jshell> i == 20;
$7 ==> false

Snippet-2

jshell> int i = 15;
i ==> 15

jshell> i >=15
$1 ==> true

jshell> i <= 15
$2 ==> true

jshell> i >= 15 && i <= 25
$3 ==> true

jshell> i == 30;
$4 ==> false

jshell> i = 30;
i ==> 30

jshell> i >= 15 && i <= 25;
$5 ==> false

In the below code snippet, we can implement logical operators using JShell.

jshell> true && true
$1 ==> true

jshell> true && false
$2 ==> false

jshell> false && true
$3 ==> false

jshell> false && false
$4 ==> false

jshell> true || true
$5 ==> true

jshell> true || false
$6 ==> true

jshell> false || true
$7 ==> true

jshell> false || false
$8 ==> false