DEV Community


Posted on


How to eliminate code duplicates in Java?

A Java developer's job doesn't end with writing code. The developer must ensure that the code is structured and functional. Removing duplicate code fragments from the program is an important step in the process of software development and maintenance.

It is worth mentioning that removing the duplicate code can be a laborious process. Still, it is essential to remember that it will improve the maintainability of the code and also reduce the risk of introducing errors and bugs. This can be achieved by using special tools for working with code. You should analyze your code and then refactor it to improve its quality.

The processes of analysis and refactoring improve the internal structure of the code and get rid of "smells", for example, as duplicated code fragments. This allows you to keep the code up-to-date and add new functions without problems.

Image description

Code Analysis for Java

Code analysis is one of the steps in writing good code. Code analysis involves reviewing and evaluating the program to identify areas with bugs, bugs, security vulnerabilities, and other problems.

  • Manual code analysis. This is code analysis line by line, performed by a software developer who specializes in code analysis. The process usually takes much time;
  • Automated static analysis. The process involves using automated tools, such as SonarQube, which will save you time. The tools analyze the code without running it.
  • Automated dynamic analysis. It involves monitoring the code being executed to detect errors, bugs, and potential vulnerabilities.
  • Hybrid approach. This method combines automated static and dynamic code analysis and its manual check.

There is also a new AppRefactoring tool on the market that analyzes the code and makes it unique. This tool will also help you in eliminating duplicates from your Java code.
Based on the results of the analysis, you can perform refactoring for the source code.

How can refactoring help?

Refactoring is changing the internal structure of Java code without changing its functionality. This process has many benefits that help the Java developer improve the quality of his code. We will cite four reasons:

  • Clean code, refactoring helps eliminate code smells and extract duplicate fragments.
  • Bug detection and correction. Refactoring makes code easier to understand, which makes it easier to find bugs in it.
  • Ease of maintenance. Conducting regular refactoring makes it easier to maintain the code.
  • Saving time and energy, refactoring Java code improves code quality without having to rewrite it. This will save your resources.

Image description

Example of refactoring for Java

For example, there is a method that compares two numbers and returns true if the first is greater and false otherwise:
public boolean max(int a, int b) {
if(a > b) {
return true;
} else if(a == b) {
return false;
} else {
return false;

This is quite a lot of code. It would seem that there is no need for the if-else block when you can write a method 6 lines shorter:
public boolean max(int a, int b) {
return a>b;

This way the code looks much easier, although it does the same action as above.
Automated code uniqueness tool for Java
Conducting analysis manually is a tedious task that consumes time and resources. In addition, it can lead to additional errors in the software. That's why you need an automated tool that can help ensure speed and improve your performance. Consider AppRefactoring, an automated analysis tool that effectively helps you work with Java code.

With AppRefactoring, you can perform a detailed analysis of your code in a few clicks. The result of the analysis gives you information about problems in your code and fragments that need to be unique. Your code is compared to other projects in your database for uniqueness, notifying you of any overlaps. While AppRefactoring analyzes and compares your projects, you can focus on your other tasks.

Image description


Refactoring is a tool that every Java developer needs because no code is perfect. By refactoring your code regularly, you get to keep it readable and clean, and functioning at the highest level. It is necessary to analyze the code to fix its errors and bugs. For analysis, it's better to use the special tools mentioned above. SonarQube, which can perform automated analysis for code. AppRefactoring - this will not only help you to analyze but will also help to make your code unique. With these tools, you won't have to worry about the long hours required to manually work with your code. AppRefactoring will help you quickly analyze your code with all the possible exceptions.

Top comments (0)

Timeless DEV post...

Git Concepts I Wish I Knew Years Ago

The most used technology by developers is not Javascript.

It's not Python or HTML.

It hardly even gets mentioned in interviews or listed as a pre-requisite for jobs.

I'm talking about Git and version control of course.

One does not simply learn git