09 JDBCTemplate

spring jdbc

引用jar包

Spring封裝的jdbc引用的jar包

JDBCTemplate_介紹

JDBCTemplate_快速入門

導入jar包

JDBCTemplate_執行DML語句

添加註解

package cn.itcast.jdbctemplate;

import cn.itcast.utils.JDBCUtils;
import org.springframework.jdbc.core.JdbcTemplate;

/**

• JdbcTemplate入門

*/
public class JdbcTemplateDemo1 {

public static void main(String[] args) {
    //1.導入jar包
    //2.建立JDBCTemplate對象
    JdbcTemplate template = new JdbcTemplate(JDBCUtils.getDataSource());
    //3.調用方法
    String sql = "update account set balance = 5000 where id = ?";
    int count = template.update(sql, 3);
    System.out.println(count);
}

}

JDBCTemplate_執行DQL語句

package cn.itcast.jdbctemplate;

import cn.itcast.domain.Emp;
import cn.itcast.utils.JDBCUtils;
import org.junit.Test;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;

import java.sql.Date;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;
import java.util.Map;

public class JdbcTemplateDemo2 {

//Junit單元測試，可讓方法獨立執行


//1. 獲取JDBCTemplate對象
private JdbcTemplate template = new JdbcTemplate(JDBCUtils.getDataSource());
/**
 * 1. 修改1號數據的 salary 爲 10000
 */
@Test
public void test1(){

    //2. 定義sql
    String sql = "update emp set salary = 10000 where id = 1001";
    //3. 執行sql
    int count = template.update(sql);
    System.out.println(count);
}

/**
 * 2. 添加一條記錄
 */
@Test
public void test2(){
    String sql = "insert into emp(id,ename,dept_id) values(?,?,?)";
    int count = template.update(sql, 1015, "郭靖", 10);
    System.out.println(count);

}

/**
 * 3.刪除剛纔添加的記錄
 */
@Test
public void test3(){
    String sql = "delete from emp where id = ?";
    int count = template.update(sql, 1015);
    System.out.println(count);
}

/**
 * 4.查詢id爲1001的記錄，將其封裝爲Map集合
 * 注意：這個方法查詢的結果集長度只能是1
 */
@Test
public void test4(){
    String sql = "select * from emp where id = ? or id = ?";
    Map<String, Object> map = template.queryForMap(sql, 1001,1002);
    System.out.println(map);
    //{id=1001, ename=孫悟空, job_id=4, mgr=1004, joindate=2000-12-17, salary=10000.00, bonus=null, dept_id=20}

}

/**
 * 5. 查詢全部記錄，將其封裝爲List
 */
@Test
public void test5(){
    String sql = "select * from emp";
    List<Map<String, Object>> list = template.queryForList(sql);

    for (Map<String, Object> stringObjectMap : list) {
        System.out.println(stringObjectMap);
    }
}

/**
 * 6. 查詢全部記錄，將其封裝爲Emp對象的List集合
 */

@Test
public void test6(){
    String sql = "select * from emp";
    List<Emp> list = template.query(sql, new RowMapper<Emp>() {

        @Override
        public Emp mapRow(ResultSet rs, int i) throws SQLException {
            Emp emp = new Emp();
            int id = rs.getInt("id");
            String ename = rs.getString("ename");
            int job_id = rs.getInt("job_id");
            int mgr = rs.getInt("mgr");
            Date joindate = rs.getDate("joindate");
            double salary = rs.getDouble("salary");
            double bonus = rs.getDouble("bonus");
            int dept_id = rs.getInt("dept_id");

            emp.setId(id);
            emp.setEname(ename);
            emp.setJob_id(job_id);
            emp.setMgr(mgr);
            emp.setJoindate(joindate);
            emp.setSalary(salary);
            emp.setBonus(bonus);
            emp.setDept_id(dept_id);

            return emp;
        }
    });


    for (Emp emp : list) {
        System.out.println(emp);
    }
}

/**
 * 6. 查詢全部記錄，將其封裝爲Emp對象的List集合
 */

@Test
public void test6_2(){
    String sql = "select * from emp";
    List<Emp> list = template.query(sql, new BeanPropertyRowMapper<Emp>(Emp.class));
    for (Emp emp : list) {
        System.out.println(emp);
    }
}

/**
 * 7. 查詢總記錄數
 */

@Test
public void test7(){
    String sql = "select count(id) from emp";
    Long total = template.queryForObject(sql, Long.class);
    System.out.println(total);
}

}