spring boot mongodb example

-annotations are grouped together so that we can simply write an annotation to represent two annotations.Example:(1) Example combination annotations Packagecom.ecworking.annotation;ImportOrg.springframework.context.annotation.ComponentScan;Importorg.springframework.context.annotation.Configuration;Importjava.lang.annotation.*; @Target (Elementtype.type) @Retention (retentionpolicy.runtime) @Documented @configuration//combining @configuration meta-anno

. For example: Spring-boot-starter-web will automatically assemble Tomcat containers , and the configuration of the Web app is automatically read from application.properties, such as: Server.port, or if the application.properties does not have the relevant parameters configured, the default configuration information, such as: 8080.

specified by the Spring.profiles.active property is added after those configured files through the Springapplication API, so the priority is higher. If you specify any files in the spring.config.location, the specific profile version of those files will not be considered. If you also want to use a specific profile attribute, use the table of contents in Spring.config.location. 24.5 placeholders in Properties When the values in Application.properties are used, they are filtered through the exist

complex. In order of precedence from highest to lowest, the specific list is as follows. command-line arguments. The Java system parameters obtained through System.getproperties (). Operating system environment variables. The JNDI attribute obtained from java:comp/env. The "random.*" property generated by Randomvaluepropertysource. apply a property file other than the Jar file . (via spring.config.location parameter) Apply the properties file inside the Jar file

Spring Boot 2.0 offers a number of new features, one of which is a small egg: dynamic Banner, and today we'll take this to taste fresh.Configuration dependenciesWith spring boot 2 You first need to replace the project dependency package with the newly released 2.0 release, and now the site https://start.spring.io/ also

configuration. about paging Plug-ins and general Mapper integration The paging plugin as an example of Plug-ins is available in the above code. The General mapper configuration is the actual configuration of the mapperscannerconfigurer when the use of Tk.mybatis.spring.mapper.MapperScannerConfigurer can be configured to use properties. the Spring boot integrated

following instruction to output the corresponding version to verify the installation success, the code is as follows:Successful output will appear in the console:Spring Boot CLI Hello World caseAfter installation, it is convenient to learn to use it under the Spring Boot CLI. For example, we learn how to write an

-annotation" > @RequestMapping ( "/") public String greeting () { return " Hello world! "; } public static void main (string[] args) {} /span> Run app: mvn spring-boot:run or run Main () method in the IDE, Access http://localhost:8080 in the browser, Hello world! appears on the page. With just more than 10 lines of Java code and a Hello World app running correctly, what exactly does this code do? We are from the entr

, throw MyException exception[Java] View plain copy@Controllerpublic class Hellocontroller {@RequestMapping("/json") public String json() throws MyException { throw new MyException("发生错误2"); } }Create a corresponding processing for a myexception exception[Java] View plain copy@ControllerAdvicepublic class Globalexceptionhandler {@ExceptionHandler(value = MyException.class) @ResponseBody public ErrorInfo}Launch app, Access: Http://localhost:8080/json, you can get the following return co

; @SpringBootApplication @RestController public class application { @RequestMapping ( "/") public String greeting () {return "Hello world!";} public static void main (string[] args) {Springapplication.run ( Application.class, args); }} Run app: mvn spring-boot:run or run Main () method in the IDE, Access http://localhost:8080 in the browser, Hello world! appears on the page. With just more than 10 lines of Java code and a Hello World app ru