Conditional statements are essential in programming, it gives us the power to control how our code runs depending on certain conditions. In Java, the if statement is a basic building block for setting up conditions in our code. When working with if-else statements that have lots of conditions, it’s crucial to enhance the way we write the code so that it’s easy to read and maintain. In this article, we’ll explore several techniques to refine our syntax, accompanied by examples for a better understanding.
Let’s consider a scenario where we want to check if a variable number is less than 5, greater than 10, or even. Below is an example illustrating the challenge:
public class MultipleOrConditionsExample < public static void main(String[] args) < int number = 7; if (number < 5) < if (number >10) < if (number % 2 == 0) < System.out.println("The number satisfies one of the conditions."); >> > System.out.println("The number does not satisfy any of the conditions."); > >
When we run the above code, we get the following output as shown in Fig 1.0
The problem includes addressing issues related to code readability, potential logical errors, and the overall maintainability of the codebase. The challenge is to come up with a solution that keeps the code easy to read and clear even when there are more conditions. This ensures that the code stays manageable and free of mistakes.
Let’s implement the above if-else statements with multiple conditions to improve readability and clarity. The above code becomes:
public class MultipleConditions < public static void main(String[] args) < int number = 7; // The following if statement has multiple 'or' conditions if (number < 5 || number >10 || number % 2 == 0) < System.out.println("The number satisfies one of the conditions."); >else < System.out.println("The number does not satisfy any of the conditions."); >> >
If we run the above code, we will get the same output shown in Fig 1.0.
To enhance the readability, maintainability, and robustness of code with multiple conditions in an if statement, consider the following approaches:
Maintain uniform and correct indentation. Use braces <> for the if and else blocks, even if they contain only a single statement. This maintains a consistent coding style and stops mistakes from happening.
if (condition1 || condition2 || condition3) < // Code block for the first condition >else if (condition4 && condition5) < // Code block for the second condition >else < // Default code block if none of the conditions is met >
When combining multiple conditions, always use parentheses to explicitly define the order of evaluation. This not only ensures that the conditions are checked in the intended sequence but also improves code readability. Without parentheses, the default operator precedence might lead to unexpected results.
// Unclear without parentheses if (number < 5 || number >10 || number % 2 == 0) < // Code block >// Clear with parentheses if ((number < 5 || number >10) || (number % 2 == 0)) < // Code block >
Nested if-else statements can quickly become complex and difficult to comprehend. Instead, think about refactoring your code to make it simpler and use logical operators to combine conditions in a smart way. This makes your code easier to read and lowers the chance of introducing mistakes.
Assign meaningful names to variables representing conditions. This makes the code self-explanatory, reducing the need for comments to explain the logic. Developers reading your code can quickly grasp the purpose of each condition.
If conditions become complex, consider extracting them into separate methods. This improves readability and allows for code reuse.
For straightforward conditions, if-else statements can be replaced with the ternary operator for more concise code. However, be careful when using this method so that you don’t compromise how easy it is to read.
// If-else statement int number = 7; if (number < 5) < // code block >if (number > 10) < //code block >else < // code block >// Ternary operator String result = (number < 5 || number >10 || number % 2 == 0) ? "Satisfies" : "Does not satisfy"; System.out.println("The number " + result + " the conditions.");
When dealing with multiple values for a single variable, consider using a switch statement instead of a long chain of if-else statements. Using switch statements makes the code easier to read, and the compiler can make it run faster.
// If-else chain if (day == 1) < // Code block >else if (day == 2) < // Code block >else if (day == 3) < // Code block >// . and so on // Switch statement switch (day) < case 1: // Code block break; case 2: // Code block break; case 3: // Code block break; // . and so on >
If you have specific values to deal with, think about using enums . They make it easy to show and compare values, which makes your code easier to manage.
enum Season < SPRING, SUMMER, AUTUMN, WINTER >Season currentSeason = Season.SUMMER; if (currentSeason == Season.SUMMER || currentSeason == Season.AUTUMN) < // Code block >
Crafting clear and efficient if-else statements with multiple conditions is a skill that enhances code readability and maintainability. By understanding the logic flow, using parentheses to clarify conditions, avoiding nested structures, employing descriptive variable names, and considering alternative constructs like switch statements and enums, you can create code that is both expressive and easy to comprehend.
This was a tutorial on Writing Clear and Efficient If-Else Statements with Multiple ‘or’ Conditions in Java.
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You can download the full source code of this example here: Java multiple or conditions in if statement.