Relational Operators in java

Java has six relational operators that compare two numbers and return a boolean value. The relational operators are <, >, <=, >=, ==, and !=.

x < y	Less than	True if x is less than y, otherwise false.
x > y	Greater than	True if x is greater than y, otherwise false.
x <= y	Less than or equal to	True if x is less than or equal to y, otherwise false.
x >= y	Greater than or equal to	True if x is greater than or equal to y, otherwise false.
x == y	Equal	True if x equals y, otherwise false.
x != y	Not Equal	True if x is not equal to y, otherwise false.

Here are some code snippets showing the relational operators.

boolean test1 = 1 < 2;  // True. One is less that two.
boolean test2 = 1 > 2;  // False. One is not greater than two.
boolean test3 = 3.5 != 1;  // True. One does not equal 3.5
boolean test4 = 17*3.5 >= 67.0 - 42; //True. 59.5 is greater than 5
boolean test5 = 9.8*54 <= 654; // True. 529.2 is less than 654
boolean test6 = 6*4 == 3*8; // True. 24 equals 24
boolean test7 = 6*4 <= 3*8; // True. 24 is less than or equal to 24
boolean test8 = 6*4 < 3*8; // False. 24 is not less than 24

This, however, is an unusual use of booleans. Almost all use of booleans in practice comes in conditional statements and loop tests. You've already seen several examples of this. Earlier you saw this

if (args.length > 0) {
  System.out.println("Hello " + args[0]);
}

args.length > 0 is a boolean value. In other words it is either true or it is false. You could write

boolean test = args.length > 0;
if (test) {
  System.out.println("Hello " + args[0]);
}

instead. However in simple situations like this the original approach is customary. Similarly the condition test in a while loop is a boolean. When you write while (i < args.length) the i < args.length is a boolean.

All relational operators are binary operators, and their operands are numeric expressions.
Binary numeric promotion is applied to the operands of these operators. The evaluation results in a boolean value. Relational operators have precedence lower than arithmetic operators, but higher than that of the assignment operators.