There are about 50+ reserved keywords in java for making the the language more sophisticated.
Among them, most of them are used in java and few are kept for future use.
Anyway, the main message of Java keywords is that, you can not use them for creating classes, variables , methods and so on. But, combination could be valid.
But it us recommended that you don't use them for defining classes, variables or methods and vice versa.
In the below chart you see list of reserved keywords in java.
| abstract | continue | for | new | switch |
| assert | default | goto | package | synchronized |
| boolean | do | if | private | this |
| byte | else | import | public | throw/throws |
| break | double | implements | protected | extends |
| case | enum | return | instanceof | transient |
| catch | int | short | double | long |
| float | try | char | final | interface |
| static | void | class | finally | strictfp |
| volatile | const | native | super | while |