Detailed explanation of spring automatic assembly and scanning annotation code

1 @ r of JavaBean_ 404_ 1860@

Automatic injection to reduce the configuration information of XML files.

2 spring scan annotation

Use spring's scanning annotation to reconstruct the three-tier structure. Configure less content

In ApplicationContext XML file, import the scanned XSD

L enable annotation scanning

Summarize with notes

Class annotation:

@Controller (annotation for web layer)

@Service (annotation for serivce layer)

@Repository (annotation for Dao layer)

@Component (annotate the Java class, which is the only annotation in the old version of spring)

The above three annotations: bring the corresponding class into the corresponding class in the spring container

ID: the first letter of the class name is lowercase (default)

If you need to specify your own ID, you need to add string class parameters to the three annotations

@controller(“uAction”)id=uAction

@Resource (annotation for the object attribute to be dependent)

Pass @ r_ 404_ 1860 @ complete the injection of dependent attributes.

Parameter: Name: @ r by byname_ 404_ 1860@

Parameter: Type: @ r by bytype_ 404_ 1860@

Annotation execution process

1. Load spring container

2. Scan the specified package in the spring container

3. Scan the specified package, add three class annotated classes, and then include them into the spring container

4,

5. Scan the attributes annotated with @ resource in the class, and then follow @ R_ 404_ 1860 @

6,Autowrie

summary

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