spring boot interview questions

Analysis:Store basic data types1. Create an arr reference in the stack2. Create an int array of length 3 in the heap and initialize it, assigning the default value of 03. Point an ARR reference to an int array4. Re-assign values to each int value in an int arrayStore reference type User1. Create a Userarr reference in the stack2. Create a user array of length 3 in the heap and initialize it, assigning a default value of NULL3. Point the Userarr reference to the user array4. Create a user1,user2

digits:"); int N=scanner.nextint (); int [] num=new int[n]; SYSTEM.OUT.PRINTLN ("Input remaining number:"); int max=integer.min_value; int min=integer.max_value; int s=0; for (int i=0;iSequence and 01 FlipLongest common continuous substringAssembling trianglesThe smallest rectangleString classificationThe beautiful palindrome stringGo to the companyAdjust formationCollectionPainting BoardSmall easy to remember wordsSplit biscuitsBuy a HatThe degree of t

client. The expression is defined between the two tags, 9. What does the implied object mean? What are the hidden objects?JSP implied objects are some Java objects in the page, and the JSP container allows these Java objects to be used by developers. Developers can use them directly without a clear statement. JSP implicit objects are also called predefined variables. The following lists the implied objects in the JSP page:ApplicationPageRequestResponseSessionexceptionOutConfigPageContext

tee filter?Answer: The tee filter is used to send output to multiple destinations. If used for pipelines, it can copy the output to one file and copy the other to the screen (or some other program).[Email protected]:~$ ll/etc | NL | Tee/tmp/ll.outIn the example above, the LL output can be captured in the/tmp/ll.out file and also displayed on the screen.Q: Export PS1 = "[Email protected]:\ $PWD: What is this command doing?]A: This export command changes the login prompt to display the user name,

firstNameYou can use the following property names: person.firstName, the standard hump-type naming person.first-name, dashed ( - ) split mode, recommended for .properties use in and .yml configuration files PERSON_FIRST_NAME, uppercase underline, recommended for use in system environment variables Property ValidationAnnotations can be used for JSR-303 validation, such as:@Component@ConfigurationProperties(prefix="connection")public class ConnectionSettings { @NotNull

}spring.datasource.username={database username}spring.datasource.passwd={database passwd} JdbcTemplate DateSourceTransactionManager will also be automatically configured. We only need to inject (@ Autowired) when using it. In addition, SpringBoot supports spring-boot-data-jpa spring-boot-data-mongodb databases.

Spring Boot and Kotlin use the Redis database configuration method, kotlinredis In addition to providing excellent automation support for common relational databases, Spring Boot also provides automated configuration support for many NoSQL databases, including Redis, MongoDB, Elasticsearch, solr and Cassandra. Use Redi

"Common Interview questions Summary folder >>>"61. The Spring IOC container relies on two layers of meaning:bean-dependent containers : That is, the bean relies on the container, where the dependency is that the container is responsible for creating the bean and managing the bean's life cycle, precisely because the container controls the creation of the bean and

, we have completed coding. Start App. java in the MyFirstSpringBoot project and enter http: // localhost: 8080/HelloWorld in the browser. The/HelloWorld request can be mapped to the @ RequestMapping of the sayHello method of rows 11th to 13, so Hello World will be output through the sayHello method! As shown in. From this program, we can understand the differences between Spring Boot and traditional

as a service You can also make a soft link to point to your jar package and add it to init. d, and then start it with a command. Example of init. d: ln -s /var/yourapp/yourapp.jar /etc/init.d/yourappchmod +x /etc/init.d/yourapp In this way, you can use the stop or restart command to manage your application. /etc/init.d/yourapp start|stop|restart Or service yourapp start|stop|restart Now, how to test, combine, and package springboot has been introduced. You can find time to study the automatic O

") userService. create ("$ username c", "$ password 3") userService. create ("$ username d", "$ password 4") userService. create ("$ username e", "$ password 5") log.info ("total users $ {userService. allUsers} ") // Delete two userservices. deleteByName ("$ username a") userService. deleteByName ("$ username B") log.info ("total users $ {userService. allUsers }")}} The JdbcTemplate described above is only the most basic operations. For more information about how to use other data access operati

bean in the spring context, but there are two applications, so the nouniquebeandefinitionexception is thrown. to get the code that the bean specifically defines from beandefinition Let's look at where H2datasource1,h2datasource2 is defined. The above process is broken in the Defaultlistablebeanfactory.resolvenamedbean (class So let's do this here (if not clear, search the IDE for how to execute the code in the breakpoint case): This.getbeandefinition

") @Configuration public class SecurityConfig extends WebSecurityConfigurerAdapter { @Override protected void configure(HttpSecurity http) throws Exception { http.formLogin().loginPage("/login.html").loginProcessingUrl("/login").permitAll(); http.logout().logoutUrl("/logout"); http.csrf().disable(); http.authorizeRequests() .antMatchers("/login.html", "/**/*.css", "/img/**", "/third-party/**").permitAll(); http.authorizeRequests().antMatchers("/api/**").permitAll().

Introduction: A number of available connection pools are provided by default under Spring Boot, druid from an open source connection pool in the Ali Department, and provides excellent monitoring capabilities beyond the connection pool, which explains how to integrate with spring boot. 1. Environmental description

. @ CacheEvict: deletes the specified cached data. Note: @ Cacheable and @ Cacheput both put the method execution results in the cache according to the specified key. @ Cacheable first checks whether data exists in the cache during execution. If yes, read from the cache directly. If no, execute the method and put the returned value into the cache. @ Cacheput first executes the method and then writes the execution result to the cache.The @ Cacheput method must be executed. Complete sample code

10 11 12 13 14 15 16 17 18 19 20 21st ?? Note the newly added three configuration class locations, where they put the package structure lower than the startup class.Startup class Location:??? package microservice.qssj;Druid Configuration class Location:?package microservice.qssj.config;4. After the above configuration, after starting the project, you can access the Druid page, such as my project port number is 30001, my access page is as foll

source code is forward thinking The most practical way is to look at the reverse There's hikari.pool in the exception, this is a SQL connection pool that I haven't seen before. Reference Https://github.com/brettwooldridge/HikariCP#configuration-knobs-baby Official configuration Https://stackoverflow.com/questions/23172643/how-to-set-up-datasource-with-spring-for-hikaricp Http://www.cnblogs.com/yjmyzz/p/my

Recently using the spring Boot+mybatis, using IntelliJ idea to develop and document some of the solutions to the problem.1, in the case of using @mapper annotation instead of the Xxmapper.xml configuration file, using annotations such as @select to configure the SQL statement, how to configure the database field name to JavaBean entity class attribute life automatic hump naming conversion?With

, you can find the corresponding JAR package under the target directory in the project directory. study-0.0.1-SNAPSHOT.jar Execute the JAR package Start a CMD or other command line tool and execute the following command. java -jar study-0.0.1-SNAPSHOT.jar Enter Http: // localhost: 8080/hello The browser will output hello,Spring Boot For specific code, see the previous S