Java if statement in one line

Assign and execute if/else conditions in single line

You can call a method inside a Ternary Operator as long as it returns a value which is of the same type as the left-side of a ternary operator, consider this example, let’s create a method that returns a value, Now see this code, this will execute just fine because type of and variable type of are the same, i.e . output: Solution 2: For putting a conditional statement on one line, you could use the ternary operator. If you want to execute methods, that do not return anything, but have some other side-effects, the ternary operator is not the right way to go.

Assign and execute if/else conditions in single line

How can I do that for example, if block checks if the condition is true or false and then execute action depends on that condition?

if (check true or false) if false do action if true do action 

Something like that do it all in the same line without blocks , it that possible ?

result = testCondition ? value1 : value2 

this statement can be read as, If testCondition is true, assign the value of value1 to result ; otherwise, assign the value of value2 to result .

In above code, if the variable a is less than b , minVal is assigned the value of a ; otherwise, minVal is assigned the value of b .

here is another example using String ,

// result is assigned the value "it's false" String result = false ? "that was true" : "it's false"; 

this examples would clear it more. It prints the salutation properly for a person’s gender:

// if `person.isMale()` then its Mr. else its Ms. return = "Thank you " + (person.isMale() ? "Mr. " : "Ms. ") + person.getLastName() + "."; 

You can call a method inside a Ternary Operator as long as it returns a value which is of the same type as the left-side of a ternary operator,

let’s create a method that returns a String value,

String answer = false ? "true" : message(); 

this will execute just fine because return type of message() and variable type of answer are the same, i.e String .

For putting a conditional statement on one line, you could use the ternary operator. Note, however, that this can only be used in assignments , i.e. if the functions actually return something and you want to assign that value to a variable.

If you want to execute methods, that do not return anything, but have some other side-effects, the ternary operator is not the right way to go. In fact, it does not even compile!

void doThis() void doThat() (condition) ? doThis() : doThat(); // does not work! 

Instead, you should just use a plain-old if-then-else . It’s also easier to read.

You can not use Ternary Operator as you can not invoke any void method (i.e. the method which do not return anything ) from Ternary Operator

As it is not the intended use of the ternary operator .

If you really want it to be achieved in 1 line, you can write:

if (condition) doThisMethod(); else doThatMethod(); 

Single line if statement without else, Answers. You don’t. The conditional operator cannot be used for a single `if` statement. The closest you could do would be to set the variable to itself in the else case: Generally speaking, if you’re asking this question then chances are you should just be using a regular `if` statement.

15 — Single-Line IF Statements in Java Programming

Get more lessons like this at http://www.MathTutorDVD.comIn this lesson, we will learn how to control the flow of a program by using an » if» statement in jav

What’s the proper way to format «if» statements in Java with multiline «ands» or «ors»?

Apparently «if», «and», and «or» are such generic search parameters that I can’t find the answer on google for my life. Which of these is the correct format according to the Java standards?

if (condition1 && condition2 && condition3) . 

or Option 2 :

if (condition1 && condition2 && condition3) . 

The Oracle/Sun guidelines («code conventions for the java tm programming language») tell us to break before an operator. And they give this example.

if ((condition1 && condition2) || (condition3 && condition4) ||!(condition5 && condition6))

Many companies that I’ve worked for adopt the Oracle/Sun guidelines as the standard for their own code.

I believe the correct answer is ++F in Eclipse 🙂

This is completely subjective. Coding standards vary from shop to shop. To steal from yshavit’s comment: Do whatever you want unless you are working in a team environment, in which case you should follow the team standards.

I’m a fan of the second pattern.

This is a preference question. But usually you want to follow the style guidelines of either your company or whoever else is working on the codebase with you. As long as it’s consistent, any style is fine.

Personally, I’d keep everything on the same line. (ever dealt with tabs vs. spaces?)

However, if you have enough conditions to fill multiple lines, you should probably break your problem into smaller pieces.

If statement — One-line if vs && in JavaScript, 3 Answers. You should use the second. Your code should say what it means. That is what is meant by writing «semantic» code. If you are writing an if condition, then you should use the if statement, because that’s what it is there for. The && is, semantically, a logical and, which should be used in cases where you …

Java one line if does not work for prints [duplicate]

If you write something like:

 boolean condition; (. ) String out = condition ? "true" : "false"; System.out.println(out); 

It works. But if you write

 condition ? System.out.println("true") : System.out.println("false"); 

you get a «not a statement» error. The «correct» way is to write (the usage of braces or «to be or not to be in one line» is out of the scope of the question):

 if (condition) System.out.println("true"); else System.out.println("false"); 

Why? The one line if s must always return a value?

EDIT: To everyone pointing out that

 condition ? System.out.println("true") : System.out.println("false"); 

is not a correct syntax, yeah I got that part. I am not asking for solutions (although the

 System.out.println(condition ? "true" : "false"); 

@Andrew Tobilko where is that stated? THAT is what I’m interested in.

EDIT2 : The accepted answer provides exactly what I wanted. Thanks

condition ? System.out.println(«true») : System.out.println(«false»); is not a statement.

In computer science, a ternary operator is an operator that takes three arguments .

System.out.println(«true») does not qualify to be an argument, as the method println() is of void type. Hence, it is not a statement.

System.out.println(condition ? «true» : «false»);

System.out.println() doesn’t return any value (returns void ). The ternary operator expects that its two parts return statements.

System.out.println(condition ? "true" : "false"); System.out.println(condition); // it's an equalent to the previous line 

Some theory from the specification:

ConditionalExpression: ConditionalOrExpression ConditionalOrExpression ? Expression : ConditionalExpression 

• The conditional operator is syntactically right-associative (it groups right-to-left). Thus, a?b:c?d:e?f:g means the same as a?b:(c?d:(e?f:g)) .
• The conditional operator has three operand expressions. ? appears between the first and second expressions, and : appears between the second and third expressions.
• The first expression must be of type boolean or Boolean , or a compile-time error occurs.
• It is a compile-time error for either the second or the third operand expression to be an invocation of a void method.

The ternary operator should be used as :

field = condition ? valueIfTrue : valueIfFalse; 

Yes, the 2 possible options, each need to have a value (which is not the case if you call a void method such as System.out.println(. ) ).

In your case you could write:

System.out.println(condition? "true" : "false"); 

This is not correct syntax(Your code):

 condition ? System.out.println("true") : System.out.println("false"); 

This acomplishes the similar goal but has correct syntax

System.out.println(Condition ? "true" : "false") 

System.out.println() is not an argument.. Thats just for printing. To actually print you need to have an actual string! «example» . And dont forget ternary operator takes three arguments.. The condition your evaluating, the 1st result if return true, and if return false.Hope this helped!

ConditionToBeEvaluated ? IfTrue : IfFalse 

Nested if in Java, Using nested if conditions, we have printed a statement. Here inner if the condition is not true. Hence else part is executed. Nested if condition comes under decision-making statement in Java. It contains several branches with an if condition inside another if condition. The syntax, code examples, and …

How does Java deal with multiple conditions inside a single IF statement

Now. Is Java smart enough to skip checking bool2 and bool2 if bool1 was evaluated to false? Does java even check them from left to right? I’m asking this because i was «sorting» the conditions inside my if’s by the time it takes to do them (starting with the cheapest ones on the left). Now I’m not sure if this gives me any performance benefits because i don’t know how Java handles this.

Yes, Java (similar to other mainstream languages) uses lazy evaluation short-circuiting which means it evaluates as little as possible.

This means that the following code is completely safe:

Also, a || b never evaluates b if a evaluates to true .

Is Java smart enough to skip checking bool2 and bool2 if bool1 was evaluated to false?

Its not a matter of being smart, its a requirement specified in the language. Otherwise you couldn’t write expressions like.

BTW if you use & and | it will always evaluate both sides of the expression.

Please look up the difference between & and && in Java (the same applies to | and || ).

& and | are just logical operators, while && and || are conditional logical operators, which in your example means that

will skip bool2 and bool3 if bool1 is false, and

will evaluate all conditions regardless of their values.

if(foo() | foo()) will print foo twice , and if(foo() || foo()) — just once .

Yes,that is called short-circuiting.

Please take a look at this wikipedia page on short-circuiting

Java — How To Write Two If Statements Into One Single, Like the answers say, to use a ternary operator you need to know what you’re going to return if neither one of those is 0. But I think you also need to question your premise: why is it important to combine things into one line of code? You don’t get improved performance by having fewer lines in your program.

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Java Short Hand If. Else (Ternary Operator)

There is also a short-hand if else, which is known as the ternary operator because it consists of three operands.

It can be used to replace multiple lines of code with a single line, and is most often used to replace simple if else statements:

Syntax

variable = (condition) ? expressionTrue : expressionFalse; 

Example

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

Example

int time = 20; String result = (time < 18) ? "Good day." : "Good evening."; System.out.println(result); 

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