Java is one of those programming languages that has dominated the technological world for quite some time now. There are countless reasons why Java turns out to be one of the most preferred programming languages. Some of the features include portability, automated garbage collection, and a gentle learning curve. Well, what stands unnoticed is the fact that Java developers tend to make certain mistakes that cannot stand ignorable. On that note, let us have a look at the top 10 Java mistakes that could cost your job as a developer.

Missing the 'break' Keyword in a Switch-Case Block

This is not that common a mistake but the fact that it sometimes remains undiscovered until runs in production turn out to be annoying. For example, if you have forgotten to put a "break" in "case 0", there are chances that the program will write "Zero" followed by "One".

Memory leaks

As Java makes use of automatic memory management, there's no need of allocating and freeing memory manually. However, that doesn't rule out the possibility of memory allocations. As long as a program creates references to objects that are not needed anymore, it will not be freed, and this is no less than a memory leak.

Neglecting Existing Libraries

Yet another Java mistake that can cost you as a developer is ignoring the innumerable amount of libraries written in Java. It is always better to try searching for available libraries. Doing so, you will definitely get a hang of Java as a programming language.

Forgetting to free resources

It is always important for Java developers to free the resource once done every time a program opens a file or network connection. Yet another area that should be paid attention to is whether any exceptions were to be thrown during operations on such resources.

Concurrent Modification Exception

Concurrent modification of collections, as known to many, is quite natural. However, when treated with usual tools from the concurrent programming toolbox such as synchronization locks, special collections adopted for concurrent modification, etc., Java developers can avoid making mistakes. Yet another area of making mistakes as far as concurrent collection modification is concerned is to create a stream from a collection, and during the stream iteration, modify the backing collection.

Excessive Garbage Allocation

Excessive garbage allocation is something that usually happens when the program creates a lot of short-lived objects. In such a situation, the garbage collector works continuously, removing unneeded objects from memory. The impact of the same is on the performance of the applications in a negative way.

Ignoring Exceptions

As a Java developer, one might not pay heed to the exceptions that come along. However, this is yet another mistake that could cost your job as a Java developer. In a majority of the cases, you need to address the issues causing these exceptions and you are good to go.

Breaking Contracts

Breaking contracts is not something that would always lead to exceptions or break code compilation. However, things can get even more complicated as it might result in a change of application behavior without any sign of danger. Erroneous code could slip into production release and lead to various undesired effects including bad UI behavior, wrong data reports, poor application performance, data loss, and more.

Using Null References without Need

Using Null references unnecessarily is also problematic, and this is something that Java developers should avoid. One of the best strategies is to use an Optional type that can either be an empty object or a wrap of some value.

Using Raw Type Instead of a Parameterized One

According to Java specifications, raw types, are either not parametrized, or non-static members of class R that are not inherited from the superclass or super-interface of R. Until the time generic types were introduced in Java, there were no alternatives to raw types. A raw type supports generic programming since version 1.5, and generics were undoubtedly a significant improvement.