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spring boot DAO之jdbcTemplate

发表于:2024-11-23 作者:热门IT资讯网编辑
编辑最后更新 2024年11月23日,依赖 org.springframework.boot spring-boot-starter-data-jpa

依赖

                    org.springframework.boot            spring-boot-starter-data-jpa                            mysql            mysql-connector-java        

application-database.properties

#初始化数据库的时候,如果错误,是否继续启动。spring.datasource.continue-on-error=false#jdbc driver.默认通过uri来自动检测。spring.datasource.driver-class-name=com.mysql.jdbc.Driver#jdbc url.连接数据库的urispring.datasource.url=jdbc:mysql://172.28.1.227:3310/fc?useUnicode=true&autoReconnect=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useServerPrepStmts=false#数据库连接用户名spring.datasource.username=fcdev#数据连接密码spring.datasource.password=123456#全限定名,连接池。默认自动检测classpathspring.datasource.type=com.zaxxer.hikari.HikariDataSource#sql脚本字符spring.datasource.sql-script-encoding=UTF-8#jdbcTemplate配置参数spring.jdbc.template.fetch-size=-1spring.jdbc.template.max-rows=-1spring.jdbc.template.query-timeout=60

源码-JdbcProperties

@ConfigurationProperties(prefix = "spring.jdbc")public class JdbcProperties {    private final Template template = new Template();    public Template getTemplate() {        return this.template;    }    /**     * {@code JdbcTemplate} settings.     */    public static class Template {        /**         * Number of rows that should be fetched from the database when more rows are         * needed. Use -1 to use the JDBC driver's default configuration.         */        private int fetchSize = -1;        /**         * Maximum number of rows. Use -1 to use the JDBC driver's default configuration.         */        private int maxRows = -1;        /**         * Query timeout. Default is to use the JDBC driver's default configuration. If a         * duration suffix is not specified, seconds will be used.         */        @DurationUnit(ChronoUnit.SECONDS)        private Duration queryTimeout;        }}       

源码-JdbcTemplateAutoConfiguration

@Configuration@ConditionalOnClass({ DataSource.class, JdbcTemplate.class })@ConditionalOnSingleCandidate(DataSource.class)@AutoConfigureAfter(DataSourceAutoConfiguration.class)@EnableConfigurationProperties(JdbcProperties.class)public class JdbcTemplateAutoConfiguration {    @Configuration    static class JdbcTemplateConfiguration {        private final DataSource dataSource;        private final JdbcProperties properties;        JdbcTemplateConfiguration(DataSource dataSource, JdbcProperties properties) {            this.dataSource = dataSource;            this.properties = properties;        }        @Bean        @Primary        @ConditionalOnMissingBean(JdbcOperations.class)        public JdbcTemplate jdbcTemplate() {            JdbcTemplate jdbcTemplate = new JdbcTemplate(this.dataSource);            JdbcProperties.Template template = this.properties.getTemplate();            jdbcTemplate.setFetchSize(template.getFetchSize());            jdbcTemplate.setMaxRows(template.getMaxRows());            if (template.getQueryTimeout() != null) {                jdbcTemplate                        .setQueryTimeout((int) template.getQueryTimeout().getSeconds());            }            return jdbcTemplate;        }    }    @Configuration    @Import(JdbcTemplateConfiguration.class)    static class NamedParameterJdbcTemplateConfiguration {        @Bean        @Primary        @ConditionalOnSingleCandidate(JdbcTemplate.class)        @ConditionalOnMissingBean(NamedParameterJdbcOperations.class)        public NamedParameterJdbcTemplate namedParameterJdbcTemplate(                JdbcTemplate jdbcTemplate) {            return new NamedParameterJdbcTemplate(jdbcTemplate);        }    }}

jdbcTemplate使用

@Repositorypublic class TestJdbcDao {    @Autowired    private JdbcTemplate jdbcTemplate;    public String getMenuNameById(int id){        return jdbcTemplate.queryForObject("select name from t_sys_menu where id = ?", new Object[]{id}, String.class);    }}

jdbcTemplate测试

@RunWith(SpringRunner.class)@SpringBootTestpublic class AppContextTest {    @Autowired    private TestJdbcDao testJdbcDao;    @Test    public void jdbcTest(){        String menuName = testJdbcDao.getMenuNameById(1);        System.out.println("menuName = " + menuName);    }
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