Using and in if statement java

If, If..else Statement in Java with Examples

When we need to execute a set of statements based on a condition then we need to use control flow statements. For example, if a number is greater than zero then we want to print “Positive Number” but if it is less than zero then we want to print “Negative Number”. In this case we have two print statements in the program, but only one print statement executes at a time based on the input value. We will see how to write such type of conditions in the java program using control statements.

In this tutorial, we will see four types of control statements that you can use in java programs based on the requirement: In this tutorial we will cover following conditional statements:

a) if statement
b) nested if statement
c) if-else statement
d) if-else-if statement

If statement

If statement consists a condition, followed by statement or a set of statements as shown below:

The statements gets executed only when the given condition is true. If the condition is false then the statements inside if statement body are completely ignored.

Example of if statement

public class IfStatementExample < public static void main(String args[])< int num=70; if( num < 100 )< /* This println statement will only execute, * if the above condition is true */ System.out.println("number is less than 100"); >> >

Nested if statement in Java

When there is an if statement inside another if statement then it is called the nested if statement.
The structure of nested if looks like this:

Statement1 would execute if the condition_1 is true. Statement2 would only execute if both the conditions( condition_1 and condition_2) are true.

Example of Nested if statement

public class NestedIfExample < public static void main(String args[])< int num=70; if( num < 100 )< System.out.println("number is less than 100"); if(num >50) < System.out.println("number is greater than 50"); >> > >

number is less than 100 number is greater than 50

If else statement in Java

This is how an if-else statement looks:

The statements inside “if” would execute if the condition is true, and the statements inside “else” would execute if the condition is false.

Example of if-else statement

public class IfElseExample < public static void main(String args[])< int num=120; if( num < 50 )< System.out.println("num is less than 50"); >else < System.out.println("num is greater than or equal 50"); >> >

num is greater than or equal 50

if-else-if Statement

if-else-if statement is used when we need to check multiple conditions. In this statement we have only one “if” and one “else”, however we can have multiple “else if”. It is also known as if else if ladder. This is how it looks:

if(condition_1) < /*if condition_1 is true execute this*/ statement(s); >else if(condition_2) < /* execute this if condition_1 is not met and * condition_2 is met */ statement(s); >else if(condition_3) < /* execute this if condition_1 & condition_2 are * not met and condition_3 is met */ statement(s); >. . . else < /* if none of the condition is true * then these statements gets executed */ statement(s); >

Note: The most important point to note here is that in if-else-if statement, as soon as the condition is met, the corresponding set of statements get executed, rest gets ignored. If none of the condition is met then the statements inside “else” gets executed.

Example of if-else-if

public class IfElseIfExample < public static void main(String args[])< int num=1234; if(num =1) < System.out.println("Its a two digit number"); >else if(num =100) < System.out.println("Its a three digit number"); >else if(num =1000) < System.out.println("Its a four digit number"); >else if(num =10000) < System.out.println("Its a five digit number"); >else < System.out.println("number is not between 1 & 99999"); >> >

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Java If . Else

You already know that Java supports the usual logical conditions from mathematics:

• Less than: a < b
• Less than or equal to: a
• Greater than: a > b
• Greater than or equal to: a >= b
• Equal to a == b
• Not Equal to: a != b

You can use these conditions to perform different actions for different decisions.

Java has the following conditional statements:

• Use if to specify a block of code to be executed, if a specified condition is true
• Use else to specify a block of code to be executed, if the same condition is false
• Use else if to specify a new condition to test, if the first condition is false
• Use switch to specify many alternative blocks of code to be executed

The if Statement

Use the if statement to specify a block of Java code to be executed if a condition is true .

Syntax

if (condition) < // block of code to be executed if the condition is true > 

Note that if is in lowercase letters. Uppercase letters (If or IF) will generate an error.

In the example below, we test two values to find out if 20 is greater than 18. If the condition is true , print some text:

Example

We can also test variables:

Example

int x = 20; int y = 18; if (x > y)

Example explained

In the example above we use two variables, x and y, to test whether x is greater than y (using the > operator). As x is 20, and y is 18, and we know that 20 is greater than 18, we print to the screen that «x is greater than y».

The else Statement

Use the else statement to specify a block of code to be executed if the condition is false .

Syntax

if (condition) < // block of code to be executed if the condition is true > else < // block of code to be executed if the condition is false > 

Example

int time = 20; if (time < 18) < System.out.println("Good day."); >else < System.out.println("Good evening."); >// Outputs "Good evening." 

Example explained

In the example above, time (20) is greater than 18, so the condition is false . Because of this, we move on to the else condition and print to the screen «Good evening». If the time was less than 18, the program would print «Good day».

The else if Statement

Use the else if statement to specify a new condition if the first condition is false .

Syntax

if (condition1) < // block of code to be executed if condition1 is true > else if (condition2) < // block of code to be executed if the condition1 is false and condition2 is true > else < // block of code to be executed if the condition1 is false and condition2 is false > 

Example

int time = 22; if (time < 10) < System.out.println("Good morning."); >else if (time < 18) < System.out.println("Good day."); >else < System.out.println("Good evening."); >// Outputs "Good evening." 

Example explained

In the example above, time (22) is greater than 10, so the first condition is false . The next condition, in the else if statement, is also false , so we move on to the else condition since condition1 and condition2 is both false — and print to the screen «Good evening».

However, if the time was 14, our program would print «Good day.»

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If statement with and or in java

Solution 1: The best way to get different behaviour from different types in Java is using polymorphism — basically, put a virtual method into your Champion type with different implementations in Wizard, Warrior, Dragon etc subtypes A chain of if-else’s based on the type of an object is a bit of an anti-pattern in Java — crying out to be refactored into a single call to a virtual method. This is simple Warrior class, in my example, it can fight only Magic and Meele : And similar to Warrior, here is Wizard : This approach is important, because it is extremely easy to add new class (like Ranger for example).

JAVA AND OR and IF

The best way to get different behaviour from different types in Java is using polymorphism — basically, put a virtual method into your Champion type with different implementations in Wizard, Warrior, Dragon etc subtypes

A chain of if-else’s based on the type of an object is a bit of an anti-pattern in Java — crying out to be refactored into a single call to a virtual method.

Why not use a 2D array to map FightCompatilibity between Challenge and Champ. Model each Champ and Challenge as enum. Maybe, take a look at Visitor Pattern. It might be useful.

This is exactly something, which should be done by class hiearchy. Like if you know, someone is Wizard, you should already known what he can attack or not, therefore you should move responsibility into that Wizard class instead of testing it externally.

I did an example with 4 classes :

In this enum are listed all attack types

This is abstract class, it only helps you define behaviour that is same for all classes. I supposed that every class has some subset of «attack types» (or something similar). In my example, I just suppose, that each class can fight only against some types of attack. In constructor, I get all the attack I can fight and then I can chack it with this canAttack.

public abstract class Champion < private ListattackTo; public Champion(AttackTypes. attack) < this.attackTo = new ArrayList<>(); this.attackTo.addAll(Arrays.asList(attack)); > public boolean canAttack(AttackTypes attackType) < for (AttackTypes attack : attackTo)< if (attack == attackType)< return true; >> return false; > > 

This is simple Warrior class, in my example, it can fight only Magic and Meele :

public class Warrior extends Champion < public Warrior()< super(AttackTypes.Magic, AttackTypes.Meele); >> 

And similar to Warrior, here is Wizard :

public class Wizard extends Champion < public Wizard()< super(AttackTypes.Ranged, AttackTypes.Magic); >> 

This approach is important, because it is extremely easy to add new class (like Ranger for example). You just add him and thats all, you dont have to anything in your already finished code.

Then you can use it as following :

 Champion wizard = new Wizard(); Champion warrior = new Warrior(); AttackTypes attackType = AttackTypes.Ranged; System.out.println("can wizard attack? : " + wizard.canAttack(attackType)); System.out.println("can warrior attack? : " + warrior.canAttack(attackType)); 

can wizard attack? : true can warrior attack? : false 

Boolean operations — How to use ‘or’ in Java?, So the statement «a equals 5 or a equals 7» is true. The || operator can only be used, in Java, where a boolean (true or false) expression is expected, such as in an if statement like the above. So pretty much in an if or a conditional operator (that ?: thing, sometimes called the ternary operator).

OR and AND functions in java?

Well let me break it up for you.

Short Circuit And & Or operator:

Non-Short Circuit And & Or operator:

Difference between Short and Non-Short Circuit Operator:

if (false && true) // As the 1st statement is false it won’t evaluate the 2nd condition

if (false & true) //Even though the 1st statement is false, it will still evaluate the 2nd condition

Um, what do you mean by «logic gates»? Do you mean || and && ?

Java — How do I use both && and, Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question.Provide details and share your research! But avoid …. Asking for help, clarification, or responding to other answers.

How do I use both && and

What you have used is assignment operator = You need to use comparison operator == in your if block.

if (computerMove == ‘R’&& playerMove ==’S’||computerMove==’S’&&playerMove==’P’|| computerMove==’P’&& playerMove==’R’)

playerMove===’P’ in your if statement

 if ((computerMove == 'R'&&playerMove == 'S')||(computerMove=='S'&&playerMove=='P')||(computerMove=='P'&&playerMove=='R')) < int r = 1; return r; >else if ((computerMove == 'R'&&playerMove = 'R')||(computerMove=='S'&&playerMove=='S')||(computerMove=='P'&&playerMove=='P')) < int r = 0; return r; >else if ((computerMove == 'S'&&playerMove == 'R')||(computerMove=='P'&&playerMove=='S')||(computerMove=='R'&&playerMove=='P'))< int r = -1; return r; 

Besides what others have said about using == instead of =, I would just use parenthesis. Doesn't hurt anything, and improves readability of the code. So your statements would look something like:

if ( (computerMove == 'R'&&playerMove =='R') || (computerMove=='S'&&playerMove=='S') || (computerMove=='P'&&playerMove=='P') ). 

Java - && (AND) and || (OR) in IF statements, Java has 5 different boolean compare operators: &, &&, |, ||, ^. & and && are "and" operators, | and || "or" operators, ^ is "xor". The single ones will check every parameter, regardless of the values, before checking the values of the parameters. The double ones will first check the left parameter and its value and if true ( ||) or … Code sampleif (str == null || str.isEmpty()) else Feedback

Using "OR" within an "IF" statement

if(positionE != -1 && (position == -1 || positionE

if (position == -1 || positionE < position) position = positionE; 

"and" and "or" statements in java, Is there a way to use both of them in the same if statement? Yes! You're totally on the right track, just missing a set of parenthesis, and a few other small mistakes! You have the right idea. You want to use two and statements, where if either the left or the right statement is true you will assign a=0, …

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