GWT Debugging Tools - Tutorial

Welcome to this tutorial on GWT debugging tools. Debugging is an essential part of the development process, and GWT provides powerful tools to help you diagnose and fix issues in your GWT applications. In this tutorial, we will explore the debugging capabilities of GWT, including tools like the Development Mode, Super Dev Mode, and browser developer tools. We will provide step-by-step instructions, examples of commands and code, and highlight common mistakes to avoid during the debugging process.

Introduction to GWT Debugging

Debugging allows you to examine and analyze your GWT code at runtime, helping you identify and resolve issues such as logic errors, performance bottlenecks, and UI glitches. GWT offers several debugging tools to facilitate this process. Let's take a closer look at a few of them:

Development Mode

The Development Mode is a built-in debugging tool provided by GWT. It allows you to run your GWT application in a development environment and provides features like code hot-swapping, remote debugging, and breakpoints. Here are the steps to use the Development Mode:

1. Compile your GWT application in Development Mode using the GWT Compiler.
2. Launch the Development Mode using the GWT Development Mode Launcher.
3. Open the application in your preferred web browser with the provided URL.
4. Use the browser plugin provided by GWT to interact with your application and set breakpoints.
5. Use the debugging features like stepping through code, inspecting variables, and modifying code on the fly.

Super Dev Mode

Super Dev Mode is an alternative to Development Mode that provides faster compilation times and improved debugging capabilities. It utilizes the browser's built-in developer tools for debugging. Here are the steps to use Super Dev Mode:

1. Compile your GWT application in Super Dev Mode using the GWT Compiler.
2. Start the Super Dev Mode server.
3. Launch your GWT application in your preferred web browser.
4. Open the browser's developer tools and navigate to the Dev Mode On page.
5. Enable Super Dev Mode and follow the instructions provided.
6. Use the browser's developer tools for debugging, including setting breakpoints, inspecting variables, and profiling.

Common Mistakes to Avoid

• Not using breakpoints effectively to narrow down the cause of the issue.
• Overlooking logging statements and not utilizing logging effectively for debugging.
• Ignoring the browser's developer tools and not leveraging their features for debugging.
• Forgetting to compile the application in the appropriate debugging mode (Development Mode or Super Dev Mode).
• Not utilizing the debugging features provided by GWT, such as code hot-swapping and remote debugging.

Frequently Asked Questions (FAQs)

1. Can I debug my GWT application in different browsers?

Yes, GWT debugging tools are compatible with various web browsers. You can debug your GWT application in browsers like Chrome, Firefox, and Internet Explorer by using the appropriate browser plugins or developer tools.

2. How can I set breakpoints in my GWT code?

To set breakpoints in your GWT code, you can use the browser's developer tools or the debugging features provided by GWT. Simply navigate to the desired line of code and click on the line number to set a breakpoint.

3. Can I debug both client-side and server-side code in GWT?

Yes, you can debug both client-side and server-side code in GWT. The Development Mode and Super Dev Mode allow you to debug client-side code, while server-side code can be debugged using standard Java debugging techniques in your preferred IDE.

Summary

In this tutorial, we explored the powerful debugging tools available for GWT and learned how to effectively debug GWT applications. We discussed the Development Mode and Super Dev Mode, providing step-by-step instructions and highlighting common mistakes to avoid. By leveraging these debugging tools, you can quickly identify and fix issues in your GWT code, resulting in more robust and reliable applications.