用于类的接口声明:class extends implements interface
包引入和包声明:import package
数据类型:boolean byte char short int long float double
某些数据类型的可先值:false true null
流程控制:break case continue default for do while if else return switch
异常处理:catch finally throw throws try
修饰符:abstract final native private protected public static synchronized transient volatile
操作符:instanceof
创建对象:new
引用:this super
方法返回类型:void