Java is one of the most popular programming languages in the world, and is used by a wide variety of industries and applications. Whether you're just starting out in your career as a programmer or looking to improve your Java skills, here are some tips on how to become a good Java programmer:

1. Start with the basics:
   Java is a complex language, so it's important to begin with the fundamentals. Make sure you have a good understanding of basic programming concepts such as variables, data types, loops, and control structures before diving into more advanced topics.

2. Practice coding:
   The more you practice coding, the better you'll become. Work on coding challenges and projects that require you to use Java, and aim to write clean, efficient code.

3. Learn from others:
   One of the best ways to become a good Java programmer is to learn from others. Attend meetups, conferences, or take online courses that focus on Java programming. Reading blogs and participating in online forums can also be a great way to learn from others' experiences and expertise.

4. Stay up to date with the latest technologies: 
   Java is a constantly evolving language, so it's important to keep up with the latest trends and technologies. Stay informed about new releases and updates to the Java language, as well as new tools and frameworks that can make your job easier.

5. Write readable and maintainable code:
   Writing code that is easy to read and maintain is crucial for becoming a good Java programmer. Use meaningful variable and method names, and comment your code to make it easier to understand and modify in the future.

6. Test your code thoroughly:
   A good Java programmer is also a good tester. Make sure to thoroughly test your code to ensure it's working as intended and free of bugs. Learn about different testing frameworks and techniques to ensure your code is of high quality.

7. Collaborate with others:
   Collaborating with other programmers can help you learn new techniques and ideas, as well as improve your ability to work on a team. Participate in group coding projects or work on open source projects to build your collaboration skills.

Becoming a good Java programmer takes time and effort, but by focusing on the basics, practicing your coding skills, learning from others, staying up to date with the latest technologies, writing readable and maintainable code, testing thoroughly, and collaborating with others, you can improve your Java programming abilities and become an expert in the field.