That means no generics, no autoboxing, and no new-style for-each loop.
那意味着没有类属性、没有自动装箱(autoboxing)，也没有新样式for - each循环。
2
Autoboxing: Rather than generating calls to the valueOf method in the wrapper class, the compiler generates calls to the constructor instead.
自动装箱：编译器不生成对包装器类的value Of方法的调用，而是生成对构造函数的调用。
3
Using the JSR 14 target mode allows you to write code that uses generics, autoboxing, and the for-each loop in the "easy" cases, which may suffice for many projects.