【Spring Data Access】NamedParameterJdbcTemplate 批量插入

妖狐艹你老母 2022-05-10 11:14 215阅读 0赞

# NamedParameterJdbcTemplate批量插入 #

`NamedParameterJdbcTemplate`类封装了`JdbcTemplate`，在此基础上提供了基于parameter的statement,

我们先了解一下`NamedParameterJdbcTemplate`提供有别于`JdbcTemplate`的批量操作接口(其实是实现了`NamedParameterJdbcOperations`接口)，下面是方法的定义

/** * Executes a batch using the supplied SQL statement with the batch of supplied arguments. * @param sql the SQL statement to execute * @param batchValues the array of Maps containing the batch of arguments for the query * @return an array containing the numbers of rows affected by each update in the batch */ int[] batchUpdate(String sql, Map<String, ?>[] batchValues); /** * Execute a batch using the supplied SQL statement with the batch of supplied arguments. * @param sql the SQL statement to execute * @param batchArgs the array of {@link SqlParameterSource} containing the batch of arguments for the query * @return an array containing the numbers of rows affected by each update in the batch */ int[] batchUpdate(String sql, SqlParameterSource[] batchArgs);

上面的方法提供两种方式来给定parameters,这里我们演示第二个方法，对于`SqlParameterSource`对象的构造，我们可以用`SqlParameterSourceUtils`这个工具类来辅助生成对应的数组对象.

示例代码如下:

1 Config.java

import org.springframework.beans.factory.annotation.Autowired; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.ComponentScan; import org.springframework.context.annotation.Configuration; import org.springframework.context.annotation.PropertySource; import org.springframework.core.env.Environment; import org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate; import org.springframework.jdbc.datasource.DriverManagerDataSource; import javax.sql.DataSource; /** * @author jiangjian */ @Configuration @ComponentScan @PropertySource("classpath:jdbc.properties") public class Config { @Autowired private Environment env; @Bean public DataSource dataSource() { DriverManagerDataSource dataSource = new DriverManagerDataSource(); dataSource.setDriverClassName(env.getProperty("spring.datasource.driver-class-name")); dataSource.setUrl(env.getProperty("spring.datasource.url")); dataSource.setUsername(env.getProperty("spring.datasource.username")); dataSource.setPassword(env.getProperty("spring.datasource.password")); return dataSource; } /** * NOTE: 注意这里我们配置的是NamedParameterJdbcTemplate,而不是JdbcTemplate * */ @Bean public NamedParameterJdbcTemplate namedParameterJdbcTemplate() { return new NamedParameterJdbcTemplate(dataSource()); } }

2 jdbc.properties文件

spring.datasource.url=jdbc:mysql://localhost/test?useUnicode=true&characterEncoding=UTF-8&allowMultiQueries=true&autoReconnect=true&failOverReadOnly=false&autoReconnectForPools=true&serverTimezone=UTC
    spring.datasource.username=root
    spring.datasource.password=root
    spring.datasource.driver-class-name=com.mysql.jdbc.Driver

3 User类

public class User { private Long id; private String name; public User() { } public User(Long id, String name) { this.id = id; this.name = name; } //..省略get set方法 @Override public String toString() { return "User{" + "id=" + id + ", name='" + name + '\'' + '}'; } }

4 主类 NamedParameterJdbcTemplateBatchOperationSample

import org.springframework.context.ApplicationContext; import org.springframework.context.annotation.AnnotationConfigApplicationContext; import org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate; import org.springframework.jdbc.core.namedparam.SqlParameterSourceUtils; import java.util.Arrays; import java.util.List; /** * @author jiangjian */ public class NamedParameterJdbcTemplateBatchOperationSample { public static void main(String[] args) { ApplicationContext ac = new AnnotationConfigApplicationContext(Config.class); NamedParameterJdbcTemplate namedParameterJdbcTemplate = ac.getBean(NamedParameterJdbcTemplate.class); namedParameterJdbcTemplate.getJdbcOperations().execute("drop table if exists user "); namedParameterJdbcTemplate.getJdbcOperations().execute("create table user(id int auto_increment primary key, name varchar(40))"); List<User> users = Arrays.asList(new User("Alice"), new User("Bob")); namedParameterJdbcTemplate.batchUpdate("insert into user(name) values (:name)", SqlParameterSourceUtils.createBatch(users)); List<User> findUsers = namedParameterJdbcTemplate.query("select * from user", (rs, rowNum) -> new User(rs.getLong(1), rs.getString(2))); findUsers.forEach(System.out::println); namedParameterJdbcTemplate.getJdbcOperations().execute("drop table user"); } }