Best Java Code Review Tools Every Developer Should Know About

In software development, code review is a critical process that helps to improve code quality, reduce errors, and maintain consistency across the codebase.

With the growing complexity of modern software systems, reviewing code manually can be a time-consuming and error-prone task. Fortunately, there are several tools available that can automate the code review process and help developers to identify potential issues quickly.

In this topic, we will explore the world of Java code review tools, discussing different types of tools, their benefits, and how they can help developers to write better code.

Java Tools to Leverage in Code Review

These software tools automate and streamline the code review process by analyzing code to identify potential issues, such as security vulnerabilities, performance bottlenecks, coding standards violations, and more.

There are various types of Java code review tools available, including static code analysis tools, code coverage tools, IDE-based code review tools, collaboration and code review tools, security code review tools, performance analysis tools, debugging tools, refactoring tools, and documentation tools.

By leveraging these tools, developers can identify and fix potential issues more quickly, resulting in higher-quality code, improved maintainability, and reduced development time. We will explore these different types of Java code review tools, their benefits, and how they can help developers write better code.

Static Code Analysis Tools:

Static code analysis tools are software tools that analyze code without actually executing it. These tools analyze the source code to identify potential issues, such as coding standards violations, security vulnerabilities, and performance bottlenecks.

They can also provide suggestions for code improvements, such as refactoring suggestions, to help developers write better code.

Here are some examples of popular static code analysis tools for Java:

1. spotbugs: spotbugs is a widely used open-source static analysis tool that detects bugs in Java code. It examines bytecode for common programming errors and provides detailed reports of any potential issues found.
2. Checkstyle: Checkstyle is an open-source static analysis tool that checks Java code for adherence to coding standards. It can detect issues such as incorrect indentation, naming conventions, and formatting.
3. PMD: PMD is a source code analyzer that detects common programming flaws in Java code. It examines code for issues such as unused variables, dead code, and inefficient code constructs.
4. SonarQube: SonarQube is a platform that integrates multiple code quality tools, including static code analysis tools. It analyzes Java code and provides comprehensive reports on code quality, security vulnerabilities, and other issues.
5. IntelliJ IDEA Inspections: IntelliJ IDEA is an Integrated Development Environment (IDE) that includes built-in static analysis tools. It can analyze Java code for a variety of issues, such as null pointer exceptions, unreachable code, and unused imports.

Static code analysis tools are typically integrated into the development process as part of a Continuous Integration (CI) pipeline.

They are run automatically as part of the build process to catch potential issues early in the development cycle.

Developers can also run them manually on specific code sections or entire codebases to get detailed feedback on code quality and potential issues.

Code Coverage Tools:

Code coverage tools are software tools that measure the extent to which the source code is executed during automated testing.

They analyze the code to determine which parts of the code were executed and which parts were not.

This information can be used to identify untested code sections and improve the overall test coverage.

Here are some examples of popular code coverage tools for Java:

1. JaCoCo: JaCoCo is a free and open-source code coverage tool that provides detailed reports on how much of the code was executed during testing. It can be integrated with popular build tools, such as Maven and Gradle, and supports multiple code coverage metrics, such as branch coverage and line coverage.
2. Cobertura: Cobertura is another popular code coverage tool for Java that provides detailed reports on code coverage metrics. It can be integrated with Ant, Maven, and Gradle, and supports multiple code coverage metrics, such as branch coverage, line coverage, and method coverage.
3. Emma: Emma is a Java code coverage tool that provides detailed reports on how much of the code was executed during testing. It can be integrated with Ant and supports multiple code coverage metrics, such as line coverage and branch coverage.

Code coverage tools are typically integrated into the development process as part of a Continuous Integration (CI) pipeline. They are run automatically as part of the build process to measure code coverage and identify untested code sections.

Developers can also use code coverage tools manually to analyze specific code sections or entire codebases to get detailed feedback on test coverage and identify areas for improvement.

IDE-Based Code Review Tools:

IDE-based code review tools are software tools that integrate with popular Integrated Development Environments (IDEs) like Eclipse, IntelliJ, and NetBeans to provide real-time feedback on code quality.

They analyze code as it is being written, highlighting potential issues and suggesting improvements to developers.

Here are some examples of popular IDE-based code review tools for Java:

1. SonarLint: SonarLint is a free and open-source plugin for popular IDEs like Eclipse, IntelliJ, and Visual Studio Code. It provides real-time feedback on code quality, highlighting potential issues as code is being written. It can detect issues such as security vulnerabilities, performance bottlenecks, and coding standards violations.
2. CodePro AnalytiX: CodePro AnalytiX is a commercial plugin for Eclipse that provides automated code review capabilities. It can detect issues such as coding standards violations, security vulnerabilities, and performance bottlenecks. It also provides detailed reports on code quality and can be integrated into the development process as part of a Continuous Integration (CI) pipeline.
3. IntelliJ IDEA Inspections: IntelliJ IDEA is an IDE that includes built-in static analysis tools. It provides real-time feedback on code quality, highlighting potential issues as code is being written. It can detect issues such as null pointer exceptions, unreachable code, and unused imports.

IDE-based code review tools are typically integrated into the development process as part of the IDE.

They provide developers with real-time feedback on code quality, helping to catch potential issues early in the development cycle.

They also encourage developers to write better code by providing suggestions for improvements and adhering to coding standards.

Collaboration and Code Review Tools:

Collaboration and code review tools are software tools that facilitate team collaboration during the code review process. They allow team members to review code, provide feedback, and suggest improvements.

Here are some examples of popular collaboration and code review tools for Java:

1. GitHub: GitHub is a web-based platform that provides version control and collaboration tools for software development teams. It allows teams to create repositories, collaborate on code, and track issues and bugs. GitHub also includes a pull request feature that allows team members to review and comment on code changes.
2. GitLab: GitLab is another web-based platform that provides version control and collaboration tools for software development teams. It includes features such as code reviews, issue tracking, and continuous integration and deployment (CI/CD) pipelines.
3. Crucible: Crucible is a standalone code review tool by Atlassian that integrates with various version control systems, including Git, Mercurial, and Subversion. It offers features like in-line commenting, change tracking, and automated review workflows.
4. Bitbucket: Bitbucket is a web-based platform that provides version control and collaboration tools for software development teams. It includes features such as code reviews, issue tracking, and CI/CD pipelines.
5. Gerrit: Gerrit is a web-based code review tool for Git repositories. It allows team members to review code changes, provide feedback, and suggest improvements. Gerrit also includes features such as access control, change tracking, and integration with Continuous Integration (CI) tools.

Collaboration and code review tools are typically integrated into the development process as part of a Continuous Integration (CI) pipeline.

They allow team members to review code changes, provide feedback, and suggest improvements, helping to catch potential issues early in the development cycle.

They also encourage collaboration and communication within development teams, improving overall code quality and team productivity.

Security Code Review Tools:

Security code review tools are software tools that check for security vulnerabilities in code. They analyze code to identify potential security issues, such as injection attacks, authentication and authorization issues, and other common vulnerabilities.

Here are some examples of popular security code review tools for Java:

1. SonarQube: SonarQube is a platform that integrates multiple code quality tools, including security code review tools. It analyzes Java code for security vulnerabilities, such as SQL injection, cross-site scripting (XSS), and buffer overflows. It provides comprehensive reports on code quality, security vulnerabilities, and other issues.
2. OWASP ZAP: OWASP ZAP is a free and open-source security testing tool that can be used for manual and automated security testing of web applications. It includes features such as automated scanning for security vulnerabilities, as well as an active scanner for detecting vulnerabilities in real-time.
3. FindSecBugs: FindSecBugs is a plugin for the SpotBugs static analysis tool that focuses on detecting security vulnerabilities in Java code. It checks for common security issues, such as SQL injection, cross-site scripting (XSS), and insecure data storage.
4. Checkmarx: Checkmarx is a commercial security code review tool that analyzes Java code for security vulnerabilities. It can detect issues such as injection attacks, cross-site scripting (XSS), and buffer overflows. Checkmarx can also provide guidance on how to fix any potential security issues.

Security code review tools are typically integrated into the development process as part of a Continuous Integration (CI) pipeline. They are run automatically as part of the build process to catch potential security vulnerabilities early in the development cycle.

Developers can also use security code review tools manually to analyze specific code sections or entire codebases to get detailed feedback on security vulnerabilities and identify areas for improvement.

Performance Analysis Tools:

Performance analysis tools are software tools that measure and optimize the performance of Java code.

They analyze code to identify potential performance bottlenecks, such as memory leaks, CPU usage, and I/O operations, and provide feedback on how to optimize the code to improve performance.

Here are some examples of popular performance analysis tools for Java:

1. JProfiler: JProfiler is a commercial performance analysis tool for Java that provides detailed reports on performance metrics, such as CPU usage, memory usage, and garbage collection. It includes features such as a memory profiler, a CPU profiler, and a thread profiler, and can be integrated into the development process as part of a Continuous Integration (CI) pipeline.
2. YourKit Java Profiler: YourKit Java Profiler is another commercial performance analysis tool for Java that provides detailed reports on performance metrics, such as CPU usage, memory usage, and garbage collection. It includes features such as a memory profiler, a CPU profiler, and a thread profiler, and can be integrated into the development process as part of a Continuous Integration (CI) pipeline.
3. VisualVM: VisualVM is a free and open-source performance analysis tool for Java that provides detailed reports on performance metrics, such as CPU usage, memory usage, and garbage collection. It includes features such as a memory profiler, a CPU profiler, and a thread profiler, and can be integrated into the development process as part of a Continuous Integration (CI) pipeline.

Performance analysis tools are typically integrated into the development process as part of a Continuous Integration (CI) pipeline. They are run automatically as part of the build process to catch potential performance issues early in the development cycle.

Developers can also use performance analysis tools manually to analyze specific code sections or entire codebases to get detailed feedback on performance metrics and identify areas for improvement.

Debugging Tools:

Debugging tools are software tools that help to identify and resolve issues in Java code.

They provide developers with a way to inspect the internal state of the code, trace program execution, and identify potential errors or bugs.

Here are some examples of popular debugging tools for Java:

1. IntelliJ IDEA Debugger: IntelliJ IDEA is an IDE that includes a built-in debugger for Java code. It allows developers to set breakpoints, step through code, and inspect variables and object state during program execution.
2. Eclipse Debugger: Eclipse is an IDE that includes a built-in debugger for Java code. It allows developers to set breakpoints, step through code, and inspect variables and object state during program execution.
3. jdb: jdb is a command-line debugger for Java code. It allows developers to set breakpoints, step through code, and inspect variables and object state during program execution. It can be used with any Java Virtual Machine (JVM).

Debugging tools are typically used during the development process to identify and resolve issues in code.

They are used to track down errors or bugs, understand how code is executing, and inspect the state of objects and variables during program execution.

To use a debugging tool, a developer typically sets a breakpoint at a specific line of code and then runs the program in debug mode.

When the program execution reaches the breakpoint, the debugging tool stops execution and allows the developer to inspect the current state of the program.

The developer can then step through the code, inspect variables and objects, and identify potential issues or bugs.

Refactoring Tools:

Refactoring tools for tools that automate the process of refactoring code. Refactoring is the process of restructuring existing code to improve its readability, maintainability, and extensibility, without changing its functionality.

Refactoring tools can automate common refactoring tasks, such as renaming variables, extracting methods, and introducing new classes, making it easier for developers to refactor code and improve its quality.

Here are some examples of popular refactoring tools for Java:

1. Eclipse Refactoring: Eclipse is an IDE that includes a built-in refactoring tool for Java code. It allows developers to perform common refactoring tasks, such as renaming variables, extracting methods, and introducing new classes, with just a few clicks.
2. IntelliJ IDEA Refactorings: IntelliJ IDEA is an IDE that includes a built-in refactoring tool for Java code. It includes a wide range of automated refactoring tasks, such as renaming, extracting, and introducing new code constructs, as well as custom refactorings that can be defined by developers.
3. NetBeans Refactoring: NetBeans is an IDE that includes a built-in refactoring tool for Java code. It allows developers to perform common refactoring tasks, such as renaming variables, extracting methods, and introducing new classes, with just a few clicks.

Refactoring tools are typically used during the development process to improve the quality of code. They are used to simplify complex code, remove duplication, and improve the overall structure and organization of code.

To use a refactoring tool, a developer typically selects a block of code, such as a method or class, and chooses the appropriate refactoring action from the IDE’s menu.

The refactoring tool then automatically modifies the code to implement the requested changes. This allows developers to perform complex refactoring tasks quickly and easily, without introducing new bugs or errors.

Documentation Tools:

Documentation tools for Java are software tools that generate documentation for Java code.

They extract information from code comments and other metadata to create easy-to-read documentation that describes the functionality and purpose of the code.

Here are some examples of popular documentation tools for Java:

1. Javadoc: Javadoc is a tool that generates documentation from Java code comments. It is included with the Java Development Kit (JDK) and can be run from the command line or from an IDE. Javadoc generates HTML pages that describe the classes, methods, and variables in the code, making it easier for developers to understand how the code works and how to use it.
2. Doxygen: Doxygen is a tool that generates documentation from code comments in various programming languages, including Java. It generates documentation in HTML, PDF, and other formats and includes features such as cross-referencing, diagrams, and call graphs. Doxygen can also generate documentation for C++, Python, and other programming languages.
3. Sphinx: Sphinx is a tool that generates documentation from code comments in various programming languages, including Java. It generates documentation in HTML, PDF, and other formats and includes features such as cross-referencing, diagrams, and call graphs. Sphinx is often used to generate documentation for Python projects, but it can also be used to generate documentation for Java projects.

Documentation tools for Java are typically used to generate documentation for code libraries and frameworks, making it easier for developers to understand how to use them.

They can also be used to generate documentation for in-house code, making it easier for new developers to understand how the code works and how to use it.

To use a documentation tool, a developer typically adds comments to the code that describe the functionality and purpose of classes, methods, and variables.

The documentation tool then extracts this information and generates easy-to-read documentation that describes the code. The generated documentation can then be distributed to other developers or users to help them understand how to use the code.

Summary

code review is an essential part of the software development process, helping to ensure that code is reliable, maintainable, and meets established standards.

By using the various tools available for Java code review, developers can catch potential issues early in the development cycle, make code more efficient, and improve overall code quality.

To get the most out of these tools, it’s important to follow best practices in code review. Some key best practices include:

1. Review code regularly: Code should be reviewed regularly, preferably on a daily basis. This ensures that potential issues are caught early and can be addressed before they become more serious problems.
2. Involve multiple reviewers: Multiple reviewers should be involved in the code review process to provide a variety of perspectives and catch potential issues that may be missed by a single reviewer.
3. Be constructive and objective: Code reviews should be conducted in a constructive and objective manner, focusing on identifying issues and providing solutions rather than assigning blame or criticism.
4. Focus on high-risk areas: High-risk areas of code, such as security vulnerabilities or performance bottlenecks, should be given extra attention during the review process.
5. Use tools to automate and streamline the review process: The various tools available for Java code review, such as static code analysis tools and IDE-based code review tools, can be used to automate and streamline the review process, making it more efficient and effective.

By following these best practices and using the various tools available, developers can create high-quality, reliable, and maintainable software systems that meet the needs of their users.