1、@Value
Read parameters from the current configuration file in the format
@Value("${TypeName}")
private Type typeName;Type conversion will be performed automatically.
2、@Component
Only classes with this annotation can be used by @Autowired.
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4. Use annotations to construct IoC containers
Reads an entire collection type from the current configuration file. For example, there is a collection configured in the current configuration file as
dog:
age: 10
type: "哈士奇"
favorite: "拆家"
Then write a class such as Dog. Note that get and set methods must be added to all attributes.
@Component
@ConfigurationProperties(prefix = "dog")
public class Dog {
private int age;
private String type;
private String favorite;
Configure the @ConfigurationProperties annotation for the class, the parameter prefix is the prefix of the collection in the configuration file, and then add the @Component annotation to it, you can introduce it in other classes, as follows
@Autowired
private Dog dog;
By the way, the annotation of the control class in springboot is @RestController, which is equivalent to @Controller plus @ResponseBody.
The method annotation in the control class is @RequestMapping, the format is as follows, multiple request names are separated by commas
@RequestMapping(value = {"/dog"} , method = RequestMethod.GET)
There are also shorthand methods @GetRequestMapping and @PostRequestMapping, which are equivalent to omitting the following methods.
4. Use annotations to construct IoC containers
Use annotations to register beans with the Spring container . <context:component-scan base-package="pagkage1[,pagkage2,…,pagkageN]"/> needs to be registered in applicationContext.xml .
For example: specify a package in base-package
1 <context:component-scan base-package="cn.gacl.java"/>
Indicates that in the cn.gacl.java package and its sub-packages, if a class has a specific annotation [@Component/@Repository/@Service/@Controller] on the header, this object will be registered as a Bean in the Spring container. . You can also specify multiple packages in <context:component-scan base-package=” ”/>, such as:
1 <context:component-scan base-package="cn.gacl.dao.impl,cn.gacl.service.impl,cn.gacl.action"/>
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4、@RestController 和 @RequestMapping
Quote: https://blog.csdn.net/qq_32881383/article/details/77982227