Eclipse/Java code completion not working

If code completion is not working in Eclipse, there are a few possible reasons:

1. Code completion may be disabled. To enable code completion, go to "Window > Preferences > Java > Editor > Content Assist" and make sure that "Auto Activation" is enabled.

2. You may not have imported the necessary classes or packages. Code completion will only suggest classes and methods that are available in the current scope. Make sure you have imported the necessary classes or packages using the import statement.

3. The project may not be set up correctly. Make sure that your project is set up correctly and that all the necessary libraries and dependencies are included.

4. There may be syntax errors in your code. Code completion will not work if there are syntax errors in your code. Make sure to fix any syntax errors before trying to use code completion.

5. Eclipse may be having issues. If none of the above solutions work, there may be issues with Eclipse itself. Try restarting Eclipse, or try re-installing it to see if that fixes the problem.