依赖注入方式

https://blog.csdn.net/Hello_World_QWP/article/details/116119502

构造器的依赖注入
Setter的依赖注入
字段变量的依赖注入
还有其它不常用的注入方式：静态工厂方法注入、动态工厂方法注入

#构造器的依赖注入
 private final InventoryMapper inventoryMapper;

    public InventoryController(InventoryMapper inventoryMapper) {
        this.inventoryMapper = inventoryMapper;
    }
Setter注入：
private InventoryMapper inventoryMapper;

 public void setInventoryMapper(InventoryMapper inventoryMapper) {
        this.inventoryMapper = inventoryMapper;
}
字段变量注入：
@Autowired
private InventoryMapper inventoryMapper;

@Autowired

@Autowired：表示自动注入，自动从spring的上下文找到合适的bean来注入