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JavaLogical Operators in Conditions


Logical Operators in Conditions

You can combine or reverse conditions usinglogical operators. These work together withif,else, andelse if to build more complex decisions.

  • && (AND) - all conditions must be true
  • || (OR) - at least one condition must be true
  • ! (NOT) - reverses a condition (true = false, false = true)

AND (&&)

Use AND (&&) whenboth conditions must be true:

Example

Test ifa is greater thanb,and ifc is greater thana:

int a = 200;int b = 33;int c = 500;if (a > b && c > a) {  System.out.println("Both conditions are true");}

Try it Yourself »


OR (||)

Use OR (||) whenat least one of the conditions can be true:

Example

Test ifa is greater thanb,or ifa is greater thanc:

int a = 200;int b = 33;int c = 500;if (a > b || a > c) {  System.out.println("At least one condition is true");}

Try it Yourself »


NOT (!)

Use NOT (!) toreverse a condition:

Example

Test ifa isnot greater thanb:

int a = 33;int b = 200;if (!(a > b)) {  System.out.println("a is NOT greater than b");}

Try it Yourself »


Real-Life Example

In real programs, logical operators are often used for access control. For example, to get access to a system, there are specific requirements:

You must be logged in, and then you either need to be an admin, or have a high security clearance (level 1 or 2):

Example

boolean isLoggedIn = true;boolean isAdmin = false;int securityLevel = 3; // 1 = highestif (isLoggedIn && (isAdmin || securityLevel <= 2)) {  System.out.println("Access granted");} else {  System.out.println("Access denied");}// Try changing securityLevel to test different outcomes://// securityLevel 1 = Access granted// securityLevel 2 = Access granted// securityLevel 3 = Access denied// securityLevel 4 = Access denied//// If isAdmin = true, access is granted.

Try it Yourself »




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