Spring入門第二十五課
阿新 • • 發佈：2017-05-28
struct java 映射 構造器 into named put per mysq
使用具名參數
直接看代碼：
db.properties
jdbc.user=root
jdbc.password=logan123
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.jdbcUrl=jdbc:mysql://localhost:3306/selective-courses-system
jdbc.initPoolSize=5
jdbc.maxPoolSize=10
applicationContext.xml
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd"> <!-- 導入資源文件 --> <context:property-placeholder location="classpath:db.properties"/> <!-- 配置C3P0數據源 --> <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <property name="user" value="${jdbc.user}"></property> <property name="password" value="${jdbc.password}"></property> <property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property> <property name="driverClass" value="${jdbc.driverClass}"></property> <property name="initialPoolSize" value="${jdbc.initPoolSize}"></property> <property name="maxPoolSize" value="${jdbc.maxPoolSize}"></property> </bean> <!-- 配置Spring的JDBCTemplate --> <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate"> <property name="dataSource" ref="dataSource"></property> </bean> <!-- 配置NamedParameterJdbcTemplate,該對象可以使用具名參數，其沒有無參的構造器，所以必須為其構造器指定參數 --> <bean id="namedParameterJdbcTemplate" class="org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate"> <constructor-arg ref="dataSource"></constructor-arg> </bean> </beans>
package logan.study.spring.jdbc; public class Student { String student_id; String student_name; String card_id; String student_class; String sex; String password; String perovince; String address; String tel; String interests; public String getStudent_id() { return student_id; } public void setStudent_id(String student_id) { this.student_id = student_id; } public String getStudent_name() { return student_name; } public void setStudent_name(String student_name) { this.student_name = student_name; } public String getCard_id() { return card_id; } public void setCard_id(String card_id) { this.card_id = card_id; } public String getStudent_class() { return student_class; } public void setStudent_class(String student_class) { this.student_class = student_class; } public String getSex() { return sex; } public void setSex(String sex) { this.sex = sex; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } public String getPerovince() { return perovince; } public void setPerovince(String perovince) { this.perovince = perovince; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } public String getTel() { return tel; } public void setTel(String tel) { this.tel = tel; } public String getInterests() { return interests; } public void setInterests(String interests) { this.interests = interests; } @Override public String toString() { return "Student [student_id=" + student_id + ", student_name=" + student_name + ", card_id=" + card_id + ", student_class=" + student_class + ", sex=" + sex + ", password=" + password + ", perovince=" + perovince + ", address=" + address + ", tel=" + tel + ", interests=" + interests + "]"; } }
package logan.study.spring.jdbc; import static org.junit.Assert.*; import java.sql.SQLException; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import javax.sql.DataSource; import org.junit.Test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import org.springframework.jdbc.core.BeanPropertyRowMapper; import org.springframework.jdbc.core.JdbcTemplate; import org.springframework.jdbc.core.RowMapper; import org.springframework.jdbc.core.namedparam.BeanPropertySqlParameterSource; import org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate; import org.springframework.jdbc.core.namedparam.SqlParameterSource; public class JDBCTest { private ApplicationContext ctx = null; private JdbcTemplate jdbcTemplate; private NamedParameterJdbcTemplate namedParameterJdbcTemplate; { ctx = new ClassPathXmlApplicationContext("applicationContext.xml"); jdbcTemplate = (JdbcTemplate) ctx.getBean("jdbcTemplate"); namedParameterJdbcTemplate = ctx.getBean(NamedParameterJdbcTemplate.class); } @Test public void testDataSource() throws SQLException { DataSource dataSource = (DataSource) ctx.getBean("dataSource"); System.out.println(dataSource.getConnection()); } /** * 使用具名參數可以使用update(String sql, SqlParameterSource paramSource)方法進行更新 * 1.SQL語句中的參數名和類的屬性名一樣。 * 2.使用SqlParameterSource的BeanPropertySqlParameterSource實現類作為參數 */ @Test public void testNamedParameterJdbcTemplate2(){ String sql = "INSERT INTO student_info (student_id,student_name) VALUES(:student_id,:student_name)"; Student student = new Student(); student.setStudent_id("100"); student.setStudent_name("小周"); SqlParameterSource paramSource = new BeanPropertySqlParameterSource(student); namedParameterJdbcTemplate.update(sql, paramSource); } /** * 可以為參數起名字 * 1.好處：若有多個參數，則不用再去對應位置，直接對應參數名，便於維護 * 2.缺點：較為麻煩 */ @Test public void testNamedParameterJdbcTemplate(){ String sql = "INSERT INTO student_info (student_id,student_name) VALUES(:si,:sn)"; Map<String,Object> paramMap = new HashMap<>(); paramMap.put("si", "HH"); paramMap.put("sn", "小樓"); namedParameterJdbcTemplate.update(sql, paramMap); } /** * 獲取單個列的值,或者做統計查詢 */ @Test public void testQueryForObject2(){ String sql = "SELECT count(*) FROM student_info"; long count = jdbcTemplate.queryForObject(sql, Long.class); System.out.println(count); } /** * 查到實體類的集合 */ @Test public void testQueryForList(){ String sql = "SELECT student_id,student_name,card_id,class student_class,sex,password,perovince,tel,interests from student_info where student_id > ?"; RowMapper<Student> rowMapper = new BeanPropertyRowMapper<>(Student.class); List<Student> students = jdbcTemplate.query(sql, rowMapper,5); System.out.println(students); } /** * 從數據庫中獲取一條記錄，實際得到對應的一個對象 * 註意不是調用queryForObject(String sql,Class<Student> requiredType,Object... args)方法！ * 而是調用queryForObject(String sql,RowMapper<Student> rowMapper,Object... args)方法！ * 1.其中的RowMapper指定如何去映射結果集的行，常用的實現類為BeanPropertyRowMapper * 2.使用SQL中列的別名完成列名和類的屬性名的映射。例如class student_class * 3.不支持級聯框架，JdbcTemplate到底是一個JDBC的小工具，而不是ORM框架。 */ @Test public void testQueryForObject(){ String sql = "SELECT student_id,student_name,card_id,class student_class,sex,password,perovince,tel,interests from student_info where student_id=?"; RowMapper<Student> rowMapper = new BeanPropertyRowMapper<>(Student.class); Student student = jdbcTemplate.queryForObject(sql, rowMapper,1); System.out.println(student); } /** * 執行批量更新，批量INSERT，UPDATE，DELETE * */ @Test public void testBatchUpdate(){ String sql = "INSERT INTO student_info (student_id,student_name) VALUES(?,?)"; List<Object[]> pss = new ArrayList<Object[]>(); pss.add(new Object[]{"009","AA"}); pss.add(new Object[]{"010","BB"}); pss.add(new Object[]{"011","CC"}); pss.add(new Object[]{"012","DD"}); pss.add(new Object[]{"013","EE"}); pss.add(new Object[]{"014","FF"}); pss.add(new Object[]{"015","GG"}); jdbcTemplate.batchUpdate(sql, pss); } /** * 執行INSERT，UPDATE，DELETE */ @Test public void testUpdate(){ String sql = "UPDATE student_info SET student_name = ? WHERE student_id = ?"; jdbcTemplate.update(sql,"小黑","002"); } }
Spring入門第二十五課