Spring3之 bean简单属性注入

DI （依赖注入）有二种： Constructor-based dependency injection and Setter-based dependency

a)、Constructor-based? DI

com.spring305.test.beanInit.po.InitSingeBean.java

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?b)、Setter-based? DI
XML
到底使用哪种来注入？
Spring3官方文档：
<!--EndFragment--> 
it is a good rule of thumb to use constructor arguments for mandatory dependencies and setters for optional dependencies。....The Spring team generally advocates setter injection
?关于一般属性的注解现没在文档上找到。。。估计那样也没多大意义。。。
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