Java is a powerful programming language designed to be used in many different environments. One of Java’s best features is its ability to run on small devices with limited memory resources such as mobile phones and tablets. Still, it can also be used on high-end servers for enterprise applications. Unfortunately, when you ignore how your code allocates and uses system memory, you may find yourself running out of available memory, causing your app to crash. This article will show you ten ways to help you avoid this problem by saving memory while using Java either in an application or in the command line environment.
Ways to Save Memory When Using Java
- Declare Variables As Final Whenever Possible: The first way to save memory when using Java is to declare your variables as final whenever possible. This will prevent them from being modified after initializing them, freeing up some additional system resources.
- Use Primitive Data Types Instead Of Objects: Another way to conserve memory is by using primitive data types instead of objects. For example, if you need to store a list of numbers, use an int array rather than the ArrayList class. The int array will take up less memory, and it can be faster since there is no need for the extra layer of indirection provided by the ArrayList class. In many cases, you can avoid creating unnecessary objects altogether. For example, if you only need to read a value from a file, don’t create a File Input Stream object. Instead, use the get Resource As Stream() method to read the file’s contents directly into a String.
- Use The String builder Class To Create Strings Instead Of The String Class: The Java String class is implemented using a char array. This means that every time you create a new String, Java has to allocate memory for the char array, even if you only need it to hold a few characters. The StringBuilder class is designed to solve this problem by providing an easy way to build up Strings without creating separate Strings each time. It uses less memory than the String class, and it can be faster since there is no need for string concatenation operations.
- Cache Frequently Used Values In Local Variables Or Methods: A final way to save memory when using Java is by caching frequently used values in local variables or methods. This can be especially useful if you are working with large data sets. For example, if you will iterate through a list of numbers, cache the first and last numbers in local variables rather than recalculating them each time. This will avoid allocating new memory for these values on each iteration.
- Store Large Arrays In A Separate File Rather Than In Memory: Another way to conserve memory when using Java is by storing large arrays in a separate file instead of in memory. This can be helpful if your application needs to access a lot of data at once. You can free up some memory for other parts of your program by storing the data externally.
- Use The Arrays Class To Sort And Search Arrays: Another way that you can save memory when using Java is by calling on the Arrays class, which contains several helpful methods such as sort(), binarySearch(), and fill(). These methods are faster than writing custom sorting or searching algorithms, so use them whenever possible to avoid wasting precious system resources.
- Use Protobufs Rather than XML Or JSON When Sending Data Over A Network Connection: If you are working with protocols say,a protobuf example, Protocol Buffers should be used instead of using other encoding formats such as JSON and XML which require parsing on the client side, potentially increasing memory usage unnecessarily by processing objects that have already been parsed at the server level.
- Don’t Box Primitives When Possible: One final thing you should do to save memory when using Java is not boxing primitives into objects when it isn’t necessary. This will reduce garbage collection issues and improve performance since fewer objects are being created on the heap at runtime.
- Use The Java.Io Package: Finally, you should use Java’s built-in I/O capabilities whenever possible to avoid writing unnecessary code yourself. For example, rather than using an external library to read text files into Strings or byte arrays, just use the FileReader and BufferedReader classes in combination with some String functions like substring(). You can do this by calling on methods such as getInputStream() for reading input from a file and getResourceAsStream()for getting access to resources that are stored externally.
- Avoid Creating Unnecessary Objects: One of the best ways to save memory when using Java is by avoiding creating unnecessary objects. You can do this differently, but some tips include using primitive data types instead of objects, declaring variables as final whenever possible, and using the StringBuilder class to create Strings.