Groovy vs Java: Detailed Comparison and Tips on the Language Choice

The latest statistics from the TIOBE Programming Community index states that Java remains one of the most popular software development languages among professional developers.

According to the TIOBE data, last year Java held the first place; this year it went down to the second position. (Source: tiobe.com)

Despite the high popularity of Java, the data from the Stack Overflow survey indicates that there is a large number of developers who no longer want to use this language.

% show the number of professional developers who are currently using Java, but no longer interested in continuing to use it. (Source: insights.stackoverflow.com)

One of the reasons why Java’s popularity is declining is that there are more convenient alternatives appearing day by day.

Apache Groovy is one of the programming languages that can complement and in some cases even replace Java.

Today, Groovy takes the 31st place in the ranking of the most popular programming languages. Earlier, it several times got into the top 20. (Source: tiobe.com)

Despite the fact that Apache Groovy is a Java-syntax-compatible programming language for the Java platform, there is still a big difference between Groovy and Java.

In this article, we’ll examine the main differences between Groovy and Java to see when each of the two languages is best to use.

Why Java Is Worth Consideration

Developers use the Java platform to work on a variety of projects, ranging from desktop, web and mobile applications to big data processing and many more.

Source: edureka.com

For many years, the Java language has been very popular, and today a lot of companies hire Java developers to get valuable software and expand business opportunities.

Why do developers prefer Java? Here are some points that can explain this:

Java Is a Mature Language

Given that the Java language is very common and time-proven, it is very stable and predictable regarding software development, especially when talking about enterprise development.

The reason for that is a very rich ecosystem of proven frameworks and libraries which Java offers to the developers.

Also, the prevalence of this language provides companies with a large pool of talents – as Java is studied at schools and universities, and for many developers this language is the first programming language they learn.

Therefore, companies that want to find a Java developer always have a large variety of potential contractors with rich experience and advanced skills in Java development.

Due to the support of Oracle and the Java community, the language is constantly evolving, which makes it even more stable and reliable.

So if Java is so widespread why should businesses consider any alternatives?

Why Groovy Is Worth Consideration

Though Java is still one of the most widely used object oriented programming languages in the IT industry, Groovy has a few benefits that make it no less effective in software development.

Groovy May Provide Even More Opportunities Than Java

Groovy is based on the power of the Java code, but beyond that, Groovy combines the strengths of other languages.

Python, Ruby, and Smalltalk, also influenced Groovy and some of its features – range data type checking, map and list literal notation, and more.

Still, Groovy can be both a static and dynamic language depending on how you use it. It is based on the grammar of Java, so every developer learning Groovy is a Java developer to some extent.

Besides that, developers who program in Groovy get access to the valuable features inspired by other development languages which facilitates the development process and makes it more efficient.

Groovy Can Complement Java

Groovy and Java have some things in common.

For instance, Groovy can be used as a scripting and programming language for the Java platform. Groovy can also work with Java libraries and code as well as be compiled to Java virtual machine (JVM) bytecode.

Java virtual machine. (Source: net-informations.com)

This way, companies are able to combine the power of both languages to get the utmost.

Apache Groovy Is Open-Source

Groovy is open-source, which allows developers to constantly improve it, as well as exchange ideas and experience.

During its lifespan, Groovy has had many active code contributors and more than 300 code committers. (Source: github.com)

Many Companies Use Apache Groovy and Benefit From It

There is a large number of companies such as Starbucks, TransferWise, Learningpod, Rumble, and Craftbase successfully using Groovy for their business needs.

Here are some of these companies. (Source: stackshare.io)

Apparently, this is not a complete list of companies, and the language is being used in a variety of spheres like CAD development, banking & finance, insurance, biomedical research, etc.

Now that we know the main advantages of both Java and Groovy, let’s see how they differ.

What Are the Main Differences Between Apache Groovy and Java

Complexity and Convenience

Java is a power-packed and “heavyweight” language which makes it quite complex to use.

On the other hand, Groovy is a functional static and dynamic JVM-based language capable of simplifying the Java development process.

For most Java developers, learning Groovy is pretty easy, which means that they can quickly learn new skills and expand the capabilities of the Java language.

One more important point is that developers note that Groovy makes unit testing much easier. Some of them even call Apache Groovy a testing-oriented development language.

For example, such tools as Spock, a specification-based and descriptive unit testing framework, expands capabilities and at the same time simplifies the unit testing process.

Source: slideshare.net

Groovy tests can be easily added to a Java system. In integrated development environments, Groovy’s syntax also provides support for running tests.

Also, there is Geb. Geb is a Groovy browser automation tool that creates E2E test scenarios. Even developers with little experience can create their own browser automation tests using this solution.

There is a number of additional technical advantages that allow Groovy developers to be more productive:

• When working with the Java code, developers have to define getters and setters methods for fields. As for Apache Groovy, getters and setters are generated automatically for class members.
• Java doesn’t support variable substitution which is allowed by Groovy when quoted.
• Groovy is a dynamic typing language, while Java is a statically typed language. Thus, with Groovy programming, developers can spend less time writing code.
• When writing code in Java, developers must finish every statement with a semicolon. In Groovy, semicolons are optional.
• Apache Groovy developers can be more productive because they don’t have to create large amounts of code, even for complex tasks.

Integration

Another difference between the two languages is that Java and Groovy have different integration capabilities.

While Java is suitable for any JVM-based apps and libraries, it can be utilized with several 3d party tools, such as Ant, Maven and Gradle.

Groovy also easily integrates with any Java libraries, objects, and tools, so it instantly delivers to an app such features as scripting capabilities, functional programming, meta-programming, and domain-specific language authoring.

Besides Java-based tools, Swagger Codegen, Micronaut Framework, Vert.x, and Grails are some other popular tools that can be integrated with Groovy.

A Swagger Codegen logo. (Source: phauer.com)

Community

Java has a huge community whose members are recognized industry professionals.

The Apache Groovy community, on the other hand, is not so mature. Still, it may seem more friendly, open-minded, and attract many young and talented developers and encourage them to learn the language.

Nevertheless, both Java and Groovy developers can always rely on the advice of colleagues, but the Java community is much bigger.

Room for Opportunity

As it was mentioned above, Groovy was greatly influenced by other programming languages, therefore it can offer developers more opportunities and features to make the work more productive and efficient. Here are some examples of these features:

• Apache Groovy borrowed range data type checking and meta-programming capabilities from the Ruby language.
• It borrowed the syntax for default parameters as well as map and list literal notation from Python.
• Smalltalk’s collection processing methods and naming scheme influenced Groovy creators.
• From Clojure and Lisp, Groovy developers took closures.

Some of the differences between Java and Apache Groovy make it possible to say that the Groovy language in some sense is a modern and advanced version of Java.

However, each language has its own specific features that should be considered when choosing a language for application development.

When It Is Better to Choose Apache Groovy and Java

On the one hand, companies use Groovy as a fairly innovative language that is well compatible with Java Virtual Machine and can greatly facilitate the work of developers, as well as speed up the project delivery.

On the other hand, Java is an extremely popular programming language  that has helped thousands of companies make their business more successful.

However, both languages may have their own strengths, weaknesses, and use cases.

When It Is Better to Use Java

Java may be a good choice if scalability and performance are critical and if the company develops web apps.

Large companies in the spheres like defense, banking and finance, healthcare, choose Java, as it is time-proven and is often used to develop complex enterprise projects.

When It Is Better to Use Groovy

Groovy programming can be successfully used for various scenarios, from experimenting with new APIs to string manipulation and data crunching.

Also, Groovy is supported by a wide range of frameworks such as Micronaut, Griffon, Spring Boot, and Ratpack which also helps simplify the work of engineers.

The choice between the two languages is situational and will depend on the specific requirements of a particular project.

If you don’t know what language will be a better fit for your project,  please feel free to contact us at SCAND. Our specialists will provide you with a free consultation and recommend you what language to choose