public Configuration parse() {
        if (parsed) {
            throw new BuilderException("Each XMLConfigBuilder can only be used once.");
        }
        parsed = true;
        parseConfiguration(parser.evalNode("/configuration"));
        return configuration;
    }
@Test
    void parse() throws IOException {
        ResourceLoader loader = new DefaultResourceLoader();
        Resource resource = loader.getResource("classpath:/MybatisXMLConfigBuilderTest.xml");
        MybatisXMLConfigBuilder builder = new MybatisXMLConfigBuilder(resource.getInputStream(), null);
        Configuration configuration = builder.parse();
        assertThat(configuration).isInstanceOf(MybatisConfiguration.class);
        assertThat(configuration.getMappedStatement("com.baomidou.mybatisplus.core.MybatisXMLConfigBuilderTest$EntityMapper.selectCount"))
            .isNotNull();
    }