In Spring framework, you can wire beans automatically with auto-wiring feature. To enable it, just define the “autowire” attribute in <bean>.
Five Auto-wiring modes are supported:
1. no: Default, no auto wiring, set it manually via “ref” attribute
2. byName: Auto wiring by property name. If the name of a bean is same as the name of other bean property, auto wire it.
3. byType: Auto wiring by property data type. If data type of a bean is compatible with the data type of other bean property, auto wire it.
4. constructor: byType mode in constructor argument.
5. autodetect: If a default constructor is found, use “autowired by constructor”; Otherwise, use “autowire by type”.