Java 关键字
Java关键字也称为保留字。关键字是充当代码键的特定单词。这些是Java预先定义的词，因此不能用作变量或对象名。
Java关键字列表
| abstract | continue | for | new | switch |
| assert | default | goto | package | synchronized |
| boolean | do | if | private | this |
| break | double | implements | protected | throw |
| byte | else | import | public | throws |
| case | enum | instanceof | return | transient |
| catch | extends | int | short | try |
| char | final | interface | static | void |
| class | finally | long | strictfp | volatile |
| const | float | native | super | while |
