• Java
• Spring
• SpringBoot

SpringBoot

Example

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>hello</groupId>
    <artifactId>test-spring-boot</artifactId>
    <version>0.1.0</version>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.4.0.RELEASE</version>
    </parent>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mariadb.jdbc</groupId>
            <artifactId>mariadb-java-client</artifactId>
            <version>1.4.4</version>
        </dependency>
        <dependency>
            <groupId>commons-dbcp</groupId>
            <artifactId>commons-dbcp</artifactId>
            <version>1.4</version>
        </dependency>

         <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>4.3.2.RELEASE</version>
        </dependency>

    </dependencies>
    <properties>
        <start-class>hello.Application</start-class>
    </properties>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
    <repositories>
        <repository>
            <id>spring-milestone</id>
            <url>http://repo.spring.io/libs-release</url>
        </repository>
    </repositories>
    <pluginRepositories>
        <pluginRepository>
            <id>spring-milestone</id>
            <url>http://repo.spring.io/libs-release</url>
        </pluginRepository>
    </pluginRepositories>
</project>

src/main/java/hello/GreetingController.java

package hello;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.beans.factory.annotation.Autowired;

import java.util.List;
import java.util.ArrayList;

@Controller
public class GreetingController {
    private final Logger logger = LoggerFactory.getLogger(GreetingController.class);
    @Autowired
    DummyDAO dummyDAO;

    public GreetingController(){
        logger.debug("Greeting controller created.");
    }

    @RequestMapping("/greeting")
    public String greeting(@RequestParam(value="name", required=false, defaultValue="World") String name, Model model) {
        logger.info("Greeting endpoint called.");
        model.addAttribute("name", name);
        return "greeting";
    }

    @RequestMapping(value="/dummy",produces="application/json")
    @ResponseBody
    public List<Dummy> dummy(){
      List<Dummy> list= new java.util.ArrayList<Dummy>();
      Dummy dummy = new Dummy();
      dummy.setFieldA("AAA");
      dummy.setFieldB("CCC");
      list.add(dummy);

      Dummy dummy2 = new Dummy();
      dummy2.setFieldA("AAA2");
      dummy2.setFieldB("CCC2");
      list.add(dummy2);

      return list;
    }

    @RequestMapping(value="/dummyname",produces="application/json")
    @ResponseBody
    public String getDummyName(){
      return dummyDAO.getNameFromDummy();
    }


}

src/main/java/hello/Application.java

package hello;

import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.SpringApplication;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Bean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;

import org.apache.commons.dbcp.BasicDataSource;
import org.springframework.jdbc.core.JdbcTemplate;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@ComponentScan
@EnableAutoConfiguration
public class Application {
    private static Logger logger;

    public static void main(String[] args) {
        logger = LoggerFactory.getLogger(Application.class);
        logger.info("Starting application");
        SpringApplication.run(Application.class, args);
    }

    @Bean(name="basicDataSource",destroyMethod="close")
    public BasicDataSource createBasicDataSource(){
      logger.info("Creating basicDataSource");
      BasicDataSource bds = new BasicDataSource();
      bds.setDriverClassName("org.mariadb.jdbc.Driver");
      bds.setUrl("jdbc:mariadb://localhost:3306/springmvchtml");
      bds.setUsername("usertest");
      bds.setPassword("usertest");
      bds.setInitialSize(3);
      return bds;
    }
/*
    @Bean(name="jdbcTemplate")
    public JdbcTemplate jdbcTemplate(){
      logger.info("Creating jdbcTemplate");
      return new JdbcTemplate( basicDataSource() );
    }
*/
    @Bean(name="jdbcTemplate")
    public JdbcTemplate createJdbcTemplate(@Autowired @Qualifier("basicDataSource") BasicDataSource bds  ){
      logger.info("Creating jdbcTemplate");
      return new JdbcTemplate( bds );
    }

}

src/main/java/hello/ThreadTimer.java

package hello;

import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;
import org.springframework.beans.factory.annotation.Autowired;
import java.text.MessageFormat;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.ArrayList;

@Component
public class ThreadTimer extends Thread {
  private int delaySeconds;
  private Logger logger;
  private boolean running;
  private Object monitor=new Object();
  private ArrayList<Object> subscribers;

  //@Autowired
  //WaitThread waitThread;

  public ThreadTimer() {
    this.logger = LoggerFactory.getLogger(ThreadTimer.class);
    logger.info("Created instance of " + this.getClass().getSimpleName());
    this.running = true;
    this.delaySeconds = 5 * 1000;
    this.setName(this.getClass().getSimpleName() + "_" + this.getName());
    this.subscribers = new ArrayList<Object>();
  }

  public void addSubscriber(Object subscriber){
    this.subscribers.add(subscriber);
  }

  @PostConstruct
  public void init() {
    logger.info("Starting the thread");
    this.start();
  }

  @Override
  public void run() {
    while (running) {
      try {
        Thread.sleep(this.delaySeconds);
        logger.info("Delay " + this.getClass().getSimpleName());

        for(Object o: this.subscribers){
          synchronized(o){
            o.notify();
          }
        }
      }
      catch (InterruptedException e) {
          logger.info("ThreadTimer interrupted exception:" + e.getMessage() );
      }
      catch (Exception e) {
          e.printStackTrace();
          logger.info("ThreadTimer exception:" + e.getMessage() );
          stopRunning();
      }
    }
    logger.info("Exited " + this.getClass().getSimpleName());
  }

  public void startRunning() {
    this.running = true;
  }

  public void stopRunning() {
    this.running = false;
  }

  public void destroy(){
    logger.info("Called destroy");
    this.stopRunning();
    this.interrupt();
  }
}

src/main/java/hello/WaitThread.java

package hello;

import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;
import java.text.MessageFormat;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;

@Component
public class WaitThread extends Thread {
  private Logger logger;
  private boolean running;
  private Object monitor;

  @Autowired
  ThreadTimer timerThread;

  public WaitThread() {
    this.logger = LoggerFactory.getLogger(WaitThread.class);
    logger.info("Created instance of " + this.getClass().getSimpleName());
    this.running = true;
    this.setName(this.getClass().getSimpleName() + "_" + this.getName());
    this.monitor=new Object();
  }

  @PostConstruct
  public void init() {
    this.timerThread.addSubscriber(this);
    logger.info("Starting the thread");
    this.start();
  }

  public void run() {
    while (running) {
      try {
        synchronized(this){
          this.wait();
          logger.info("Notification received.");
        }
      }
      catch (InterruptedException e) {
          logger.info("ThreadTimer interrupted exception:" + e.getMessage() );
      }
      catch (Exception e) {
          logger.info("WaitThread exception:" + e.getMessage() );
          stopRunning();
      }
    }
    logger.info("Exited " + this.getClass().getSimpleName());
  }

  public void startRunning() {
    this.running = true;
  }

  public void stopRunning() {
    this.running = false;
  }

  public void destroy(){
    logger.info("Called destroy");
    this.stopRunning();
    this.interrupt();
  }
}

src/main/java/hello/Dummy.java

package hello;

public class Dummy{
  private String fieldA;
  private String fieldB;

  public Dummy(){
  }

  public String getFieldA(){
    return fieldA;
  }

  public String getFieldB(){
    return fieldB;
  }

  public void setFieldA(String arg){
    fieldA = arg;
  }

  public void setFieldB(String arg){
    fieldB = arg;
  }
}

src/main/java/hello/DummyDAO.java

package hello;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Component;

@Component
public class DummyDAO {
  @Autowired
  @Qualifier("jdbcTemplate")
  private JdbcTemplate jdbcTemplate;
  private Logger logger;

  public DummyDAO() {
    logger = LoggerFactory.getLogger(DummyDAO.class);
    logger.info("Created " + this.getClass().getSimpleName());
  }

  public String getNameFromDummy() {
    return this.jdbcTemplate.queryForObject("select name from dummy limit 1", String.class);
  }
}

src/main/resources/templates/greeting.html

<!DOCTYPE HTML>
<html xmlns:th="http://www.thymeleaf.org">
<head>
    <title>Getting Started: Serving Web Content</title>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
</head>
<body>
    <p th:text="'Hello, ' + ${name} + '!'" />
</body>
</html>