Java is a popular programming language used to create software applications for various platforms. Understanding how to convert long to integer in Java is an essential skill for any programmer. This article will provide a stepbystep guide on how to convert long data type to an integer in Java. We will also explain the differences between long and integer data types and the various methods available to achieve this conversion.
Key Takeaways
 Converting long to integer is a fundamental skill for Java programmers.
 Understanding the differences between long and integer data types is crucial before proceeding with the conversion process.
 Typecasting and the intValue() method are two common methods used to convert long to integer in Java.
 Handling overflow and underflow cases is necessary when converting long to integer in Java.
 The Math class in Java offers a method to perform this conversion effectively.
Understanding Long and Integer Data Types in Java
Before we dive into the conversion process, it’s important to understand the differences between the long and integer data types in Java. Both are numerical data types used to store whole numbers, but they differ in range and size.
The long data type is a 64bit signed two’s complement integer. It has a range of 9,223,372,036,854,775,808 to 9,223,372,036,854,775,807, which allows it to store larger numbers than the integer data type.
The integer data type, on the other hand, is a 32bit signed two’s complement integer with a range of 2,147,483,648 to 2,147,483,647.
When converting a long to an integer, it’s important to consider the range of both data types to ensure that the value being converted falls within the range of the integer data type.
To convert a long to an integer, there are several methods available that we will explore in the following sections.
Converting Long to Integer Using Typecasting
Typecasting is a simple method to convert a long variable to an int data type. This technique entails specifying the target data type in parentheses before the long variable. Typecasting is widely used in Java to convert one data type to another, including long to int.
The following Java code example demonstrates the conversion of a long variable to an int.
// Declare a long variable
long longVariable = 123456789;// Convert the long variable to an int using typecasting
int intVariable = (int) longVariable;// Print the int variable to the console
System.out.println(“The integer value of the long variable is: ” + intVariable);
In the code above, we first declare a long variable called longVariable and assign it a value of 123456789. We then use typecasting to convert this long variable to an int data type, assigning the result to a new variable called intVariable. Finally, we print the value of intVariable to the console.
Using typecasting is a quick and efficient way to convert a long variable to an integer in Java. However, it’s critical to keep in mind that this conversion technique may cause data loss if the long variable exceeds the maximum value that can be stored in an int variable. It’s also crucial to handle overflow and underflow cases to avoid program errors or incorrect output.
Converting Long to Integer Using the intValue() Method
When it comes to converting long values to ints in Java, one method is to use the intValue() method. This method will convert a long value to an Integer object and then retrieve the int value of that object. However, it’s essential to note that this method might not be the most efficient approach in terms of performance.
To convert a long to an int using the intValue() method, follow these steps:
 Create a Long object and initialize it with the value you wish to convert.
 Call the intValue() method on the Long object to retrieve its int value.
Long myLongValue = 123456L;
int myIntValue = myLongValue.intValue();
It’s crucial to note that this method will only work if the long value is within the range of the int data type. If the long variable has a value outside the range of the int data type, the result will be a truncated representation of the original value, leading to potential data loss.
Overall, the intValue() method can be a useful approach to convert long values to ints in Java programming. However, it’s essential to understand its limitations and use it appropriately based on your specific program’s requirements.
Handling Overflow and Underflow Cases
When converting a long variable to int in java programming, it’s essential to handle overflow and underflow cases. An overflow occurs when the long value is greater than the maximum value that can be stored in an int data type. Similarly, an underflow happens when the long value is less than the minimum value of an int data type.
To handle overflow and underflow cases while converting long to int in java with an example, we can use if statements to check the range of the long value. If the long value is within the range of int data type, we can safely convert it to int. Otherwise, we need to handle the overflow and underflow cases.
“Suppose you have a long variable ‘myLong’ with a value of 2147483648. If you try to convert it to int using typecasting, you will get 2147483648 because the long value exceeds the range of int type.”
One way to handle overflow and underflow cases is by truncating the long value and keeping the least significant 32 bits. We can achieve this by using the bitwise AND operator and masking the value with (2^32)1:
Code Example: 

long myLong = 3000000000L;

The output of the above code will be:
Output: 

Long Value: 3000000000

As shown in the example, we first check if the long value is within the range of int data type. If it is not, we mask the value with (2^32)1 to keep the least significant 32 bits. The final output shows that the long value of 3000000000 is converted to an int value of 1294967296.
By handling overflow and underflow cases appropriately while converting long values to int in java, we can avoid unexpected results and ensure our code functions correctly.
Converting Long to Integer Using the Math Class
The Math class in Java provides various methods to perform mathematical operations, including converting long values to int. The Math.toIntExact() method is an efficient and straightforward way to convert long to int while avoiding overflow and underflow conditions. This approach is suitable when you have a single long value to convert.
Here’s an example:
// Define a long variable
long myLong = 2147483648L;// Convert long to int using the Math class
int myInt = Math.toIntExact(myLong);// Output the result
System.out.println(myInt);
The method throws an ArithmeticException if the long value exceeds the range of the int data type. Therefore, you should use this method carefully and handle any exceptions that may occur.
The Math class also provides other methods to perform mathematical operations on long and int data types. For example, you can use the Math.floor() method to round down a floatingpoint value to the nearest integer, and then convert it to an int. Here’s an example:
// Define a double variable
double myDouble = 123.45;// Round down the double value
double rounded = Math.floor(myDouble);// Convert the rounded value to an int
int myInt = (int) rounded;// Output the result
System.out.println(myInt);
In this example, we first round down the double value using the Math.floor() method, which returns a double value. Then, we convert this value to an int by using typecasting. Finally, we output the result.
Using the Math class to convert long to int offers a versatile and flexible approach for handling large numbers. Be sure to experiment with the different methods available and choose the appropriate method based on your specific programming requirements.
Conclusion
Converting a long data type to an integer in Java is a valuable skill for any programmer. It allows you to handle large numbers effectively and ensures your code remains accurate. Throughout this article, we have explored different methods and techniques for converting long to int in Java. By understanding these methods, you can choose the appropriate one for your program’s specific requirements.
Remember, when converting long values to int, it’s essential to handle overflow and underflow cases appropriately. Utilizing the Math class or the intValue() method can help you achieve this. Typecasting is another technique to consider when converting long values to int. You can practice by using the code examples provided in this article.
Keep Refining Your Skills
Programming requires constant practice and refinement of your skills. Keep learning about different programming techniques and exploring new ways to convert long data types to int in Java. With dedication and consistent practice, you’ll become a proficient Java programmer in no time!
FAQ
Q: How do I convert a long to an integer in Java?
A: To convert a long data type to an integer in Java, you can use typecasting. Typecasting involves explicitly specifying the desired data type in parentheses before the value you want to convert. Here’s an example code snippet:
long longValue = 123456789L;
int intValue = (int) longValue;
After typecasting, the long value will be converted to an integer. Keep in mind that if the long value exceeds the range of the integer data type, overflow or underflow may occur, leading to unexpected results.
Q: What is the difference between long and integer data types in Java?
A: The long and integer data types in Java differ in their size and the range of values they can store. The long data type is a 64bit signed two’s complement integer, capable of storing values from 9,223,372,036,854,775,808 to 9,223,372,036,854,775,807. On the other hand, the integer data type is a 32bit signed two’s complement integer, with a range of 2,147,483,648 to 2,147,483,647. Therefore, the long data type can store larger values than the integer data type.
Q: Can I convert a long value to an integer using the intValue() method?
A: No, the intValue() method is not available for long data types in Java. This method is specifically designed for converting objects of the Integer class to int values. To convert a long value to an integer, you need to use typecasting or other appropriate techniques, as discussed in the previous answers.
Q: How should I handle overflow and underflow cases when converting a long to an integer?
A: When converting a long value to an integer, it’s essential to handle overflow and underflow cases. Overflow occurs when the long value is larger than the maximum value that can be stored in an int data type, while underflow occurs when the long value is smaller than the minimum int value. To handle these cases, you can perform range checks before the conversion and handle any exceptions or adjust your logic accordingly. It’s crucial to ensure that the converted value will not lose significant information or produce unexpected results.
Q: How can I convert a long to an integer using the Math class?
A: The Math class in Java provides the round() method, which can be used to convert a long value to an int. The round() method rounds the floatingpoint value to the nearest integer. To perform the conversion, you can use the following code:
long longValue = 123456789L;
int intValue = Math.round(longValue);
This method may be useful if you need to round the long value before converting it to an integer.