SpringBoot + Oracle JDBC

build.gradle

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-data-jdbc'
    implementation 'com.oracle.database.jdbc:ojdbc8:19.6.0.0'
    implementation 'com.oracle.database.jdbc:ucp:19.6.0.0'
}

DataSourceConfig.java

package com.acme.ucp;

import oracle.ucp.jdbc.PoolDataSource;
import oracle.ucp.jdbc.PoolDataSourceFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;

import javax.sql.DataSource;
import java.sql.SQLException;

@Configuration
public class DataSourceConfig {
    @Value("${spring.datasource.url}")
    private String url;
    @Value("${spring.datasource.username}")
    private String username;
    @Value("${spring.datasource.password}")
    private String password;
    @Value("${oracle.ucp.minPoolSize}")
    private String minPoolSize;

    @Value("${oracle.ucp.maxPoolSize}")
    private String maxPoolSize;

    @Value("${spring.datasource.driver-class-name:oracle.jdbc.pool.OracleDataSource}")
    private String driverClassName;

    @Bean(name = "OracleUniversalConnectionPool")
    @Primary
    public DataSource getDataSource() {
        PoolDataSource pds = null;
        try {
            pds = PoolDataSourceFactory.getPoolDataSource();

            pds.setConnectionFactoryClassName(driverClassName);
            pds.setURL(url);
            pds.setUser(username);
            pds.setPassword(password);
            pds.setMinPoolSize(Integer.valueOf(minPoolSize));
            pds.setInitialPoolSize(10);
            pds.setMaxPoolSize(Integer.valueOf(maxPoolSize));

        } catch (SQLException ea) {
            System.err.println("Error connecting to the database: " + ea.getMessage());
        }

        return pds;
    }
}

pom.xml

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-jdbc</artifactId>
</dependency>
<dependency>
    <groupId>com.oracle.database.jdbc</groupId>
    <artifactId>ojdbc8</artifactId>
    <version>19.6.0.0</version>
</dependency>
<dependency>
    <groupId>com.oracle.database.jdbc</groupId>
    <artifactId>ucp</artifactId>
    <version>19.6.0.0</version>
</dependency>