Application.java

package hello;

import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;

import hello.model.Customer;
import hello.model.Quote;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.client.RestTemplateBuilder;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.web.client.RestTemplate;

@SpringBootApplication
public class Application implements CommandLineRunner {

    private static final Logger log = LoggerFactory.getLogger(Application.class);

    public static void main(String[] args) {

        ApplicationContext ctx = SpringApplication.run(Application.class, args);
        
        System.out.println("Let's inspect the beans provided by Spring Boot:");
        
        String[] beanNames = ctx.getBeanDefinitionNames();
        Arrays.sort(beanNames);
        for (String beanName : beanNames) {
            System.out.println(beanName);
        }

        RestTemplate restTemplate =  new RestTemplate();
        try {
            Quote quote = restTemplate.getForObject("https://gturnquist-quoters.cfapps.io/api/random", Quote.class);
            log.info(quote.toString());
        } catch (Exception e) {
            log.warn("Could not reach external quote service: {}", e.getMessage());
        }
    }


    @Bean
    public RestTemplate restTemplate(RestTemplateBuilder builder) {
        return builder.build();
    }

    @Bean
    public CommandLineRunner run(RestTemplate restTemplate) throws Exception {
        return args -> {
            try {
                Quote quote = restTemplate.getForObject(
                        "https://gturnquist-quoters.cfapps.io/api/random", Quote.class);
                log.info(quote.toString());
            } catch (Exception e) {
                log.warn("Could not reach external quote service: {}", e.getMessage());
            }
        };
    }


    @Autowired
    JdbcTemplate jdbcTemplate;

    @Override
    public void run(String... args) throws Exception {
        log.info("Creating tables");

        jdbcTemplate.execute("DROP TABLE customers IF EXISTS");
        jdbcTemplate.execute("CREATE TABLE customers(id SERIAL, first_name VARCHAR(255), last_name VARCHAR(255))");

        // Split up the array of whole names into an array of first/last names
        List<Object[]> splitUpNames = Arrays.asList("John Woo", "Jeff Dean", "Josh Bloch", "Josh Long")
                .stream()
                .map(name -> name.split(" "))
                .collect(Collectors.toList());

        // Use a Java 8 stream to print out each tuple of the list
        splitUpNames.forEach(name -> log.info(String.format("Inserting customer record for %s %s", name[0], name[1])));

        // Uses JdbcTemplate's batchUpdate operation to bulk load data
        jdbcTemplate.batchUpdate("INSERT INTO customers(first_name, last_name) VALUES (?,?)", splitUpNames);

        log.info("Querying for customer records where first_name = 'Josh':");
        jdbcTemplate.query(
                "SELECT id, first_name, last_name FROM customers WHERE first_name = ?",
                (rs, rowNum) -> new Customer(rs.getLong("id"), rs.getString("first_name"), rs.getString("last_name")),
                "Josh"
        ).forEach(customer -> log.info(customer.toString()));

    }
}