Spaces should be used for for indentation (not tabs). The IDEs can be configured to use spaces.
Opening curly brace, {, should not be on its own line. Example:
if (true) {
First sentence in Javadoc should end with a period: .
Auto-format Code with IntelliJ
IntelliJ IDEA's built-in formatter can be configured to enforce Sun/Oracle Java code conventions automatically. For more information, see IntelliJ IDEA: Reformat code.
In IntelliJ, you can adjust the settings under Settings → Editor → Code Style → Java. The sample formatting schema can be imported directly into IntelliJ to apply the expected style more easily.
The provided schema is unofficial and may not fully conform to Oracle's Java code conventions. It serves as a baseline and should be adjusted as needed.