原来的配置文件

spring.datasource.driver-class-name=com.alibaba.druid.proxy.DruidDriver spring.datasource.url=jdbc:oracle:thin:@127.0.0.1:1521:orcl spring.datasource.username=erose spring.datasource.password=EROSE spring.datasource.type=com.alibaba.druid.pool.DruidDataSource mybatis-plus.mapper-locations=classpath:mapper/*_mapper.xml 

后来的配置文件

讯享网

讯享网spring.datasource.driver-class-name=oracle.jdbc.driver.OracleDriver spring.datasource.url=jdbc:oracle:thin:@127.0.0.1:1521:orcl spring.datasource.username=erose spring.datasource.password=EROSE spring.datasource.type=com.alibaba.druid.pool.DruidDataSource mybatis-plus.mapper-locations=classpath:mapper/*_mapper.xml 

将DruidDriver替换为oracleDriver后问题得到了解决。
具体原因尚未可知，如有大佬答复，不胜感激。
另附上Oracle配置文件

package com.positioningsystem.configuration; import com.alibaba.druid.pool.DruidDataSource; import org.apache.ibatis.session.SqlSessionFactory; import org.mybatis.spring.SqlSessionFactoryBean; import org.mybatis.spring.annotation.MapperScan; import org.mybatis.spring.mapper.MapperScannerConfigurer; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.beans.factory.annotation.Value; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.context.annotation.Primary; import org.springframework.context.support.PropertySourcesPlaceholderConfigurer; import org.springframework.core.io.support.PathMatchingResourcePatternResolver; import javax.sql.DataSource; import java.sql.SQLException; @Configuration public class DBConfiguration { 
    @Value("${spring.datasource.url}") private String url; @Value("${spring.datasource.username}") private String username; @Value("${spring.datasource.password}") private String passowrd; @Value("${spring.datasource.driver-class-name}") private String drivername; private static final String mapperlocations = "classpath:mapper/*.xml"; private static final String pageScanse = "com.positioningsystem.dao"; @Primary @Bean(name = "mainDatabase") @ConfigurationProperties(prefix = "spring.datasource") public DataSource druid(){ 
    DruidDataSource druidDataSource = new DruidDataSource(); druidDataSource.setInitialSize(30); druidDataSource.setMaxActive(200); druidDataSource.setMinIdle(50); druidDataSource.setMaxWait(); try { 
    druidDataSource.setFilters("stat,wall"); }catch (SQLException e){ 
    e.printStackTrace(); } return druidDataSource; } @Bean(name = "mainSqlSessionFactory") @Primary public SqlSessionFactory getSqlSessionFactory(@Qualifier("mainDatabase") DataSource dataSource) throws Exception{ 
    SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean(); sqlSessionFactoryBean.setDataSource(dataSource); sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(mapperlocations)); sqlSessionFactoryBean.setTypeAliasesPackage(pageScanse); return sqlSessionFactoryBean.getObject(); } }