数据库配置的通用做法是配置在配置文件中，譬如application.yml,application.properties中；但在有些情况下，开发人员并不想将数据库的配置信息放置在配置文件中，若未做脱敏处理，数据库的地址，用户名，密码等信息就会有暴露的风险

数据库配置在配置文件中

spring:
  datasource:
    url: jdbc:postgresql://localhost:5432/postgres?useSSL=false&stringtype=unspecified
    username: postgres
    password: ******
    driver-class-name: org.postgresql.Driver

数据库配置在Configuration中

import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.sql.DataSource;

@Configuration
public class DataSourceConfig {
    @Bean
    public DataSource dataSource() {
        DataSourceBuilder dataSourceBuilder = DataSourceBuilder.create();
        dataSourceBuilder.driverClassName("org.postgresql.Driver");
        dataSourceBuilder.url("jdbc:postgresql://localhost:5432/postgres?useSSL=false&stringtype=unspecified");
        dataSourceBuilder.username("postgres");
        dataSourceBuilder.password("******");
        return dataSourceBuilder.build();
    }
}