【技能库】--Spring JDBC framework with JdbcTemplate class（176）

理解Spring JDBC 和 JdbcTemplate 完整实例：学生DAO–实现

步骤：
Steps Description
1 Create a project with a name SpringExample and create a package com.tutorialspoint under the src folder in the created project.
2 Add required Spring libraries using Add External JARs option as explained in the Spring Hello World Example chapter.
3 Add Spring JDBC specific latest libraries mysql-connector-java.jar, org.springframework.jdbc.jar and org.springframework.transaction.jar in the project. You can download required libraries if you do not have them already.
4 Create DAO interface StudentDAO and list down all the required methods. Though it is not required and you can directly write StudentJDBCTemplate class, but as a good practice, let’s do it.
5 Create other required Java classes Student, StudentMapper, StudentJDBCTemplate and MainApp under the com.tutorialspoint package.
6 Make sure you already created Student table in TEST database. Also make sure your MySQL server is working fine and you have read/write access on the database using the give username and password.
7 Create Beans configuration file Beans.xml under the src folder.
8 The final step is to create the content of all the Java files and Bean Configuration file and run the application as explained below.

1 创建数据库

CREATE TABLE Student(   ID   INT NOT NULL AUTO_INCREMENT,   NAME VARCHAR(20) NOT NULL,   AGE  INT NOT NULL,   PRIMARY KEY (ID));

2 Following is the content of the Data Access Object interface file StudentDAO.java

import java.util.List;import javax.sql.DataSource;public interface StudentDAO {   /**       * This is the method to be used to initialize      * database resources ie. connection.   */   public void setDataSource(DataSource ds);   /**       * This is the method to be used to create      * a record in the Student table.   */   public void create(String name, Integer age);   /**       * This is the method to be used to list down      * a record from the Student table corresponding      * to a passed student id.   */   public Student getStudent(Integer id);   /**       * This is the method to be used to list down      * all the records from the Student table.   */   public List<Student> listStudents();   /**       * This is the method to be used to delete      * a record from the Student table corresponding      * to a passed student id.   */   public void delete(Integer id);   /**       * This is the method to be used to update      * a record into the Student table.   */   public void update(Integer id, Integer age);}

3 Following is the content of the Student.java

public class Student {   private Integer age;   private String name;   private Integer id;   public void setAge(Integer age) {      this.age = age;   }   public Integer getAge() {      return age;   }   public void setName(String name) {      this.name = name;   }   public String getName() {      return name;   }   public void setId(Integer id) {      this.id = id;   }   public Integer getId() {      return id;   }}

4 Following is the content of the StudentMapper.java

import java.sql.ResultSet;import java.sql.SQLException;import org.springframework.jdbc.core.RowMapper;public class StudentMapper implements RowMapper<Student> {   public Student mapRow(ResultSet rs, int rowNum) throws SQLException {      Student student = new Student();      student.setId(rs.getInt("id"));      student.setName(rs.getString("name"));      student.setAge(rs.getInt("age"));      return student;   }}

5 Following is the implementation class file StudentJDBCTemplate.java for the defined DAO interface StudentDAO

import java.util.List;import javax.sql.DataSource;import org.springframework.jdbc.core.JdbcTemplate;public class StudentJDBCTemplate implements StudentDAO {   private DataSource dataSource;   private JdbcTemplate jdbcTemplateObject;   public void setDataSource(DataSource dataSource) {      this.dataSource = dataSource;      this.jdbcTemplateObject = new JdbcTemplate(dataSource);   }   public void create(String name, Integer age) {      String SQL = "insert into Student (name, age) values (?, ?)";      jdbcTemplateObject.update( SQL, name, age);      System.out.println("Created Record Name = " + name + " Age = " + age);      return;   }   public Student getStudent(Integer id) {      String SQL = "select * from Student where id = ?";      Student student = jdbcTemplateObject.queryForObject(SQL,          new Object[]{id}, new StudentMapper());      return student;   }   public List<Student> listStudents() {      String SQL = "select * from Student";      List <Student> students = jdbcTemplateObject.query(SQL, new StudentMapper());      return students;   }   public void delete(Integer id) {      String SQL = "delete from Student where id = ?";      jdbcTemplateObject.update(SQL, id);      System.out.println("Deleted Record with ID = " + id );      return;   }   public void update(Integer id, Integer age){      String SQL = "update Student set age = ? where id = ?";      jdbcTemplateObject.update(SQL, age, id);      System.out.println("Updated Record with ID = " + id );      return;   }}

6 Following is the content of the MainApp.java

import java.util.List;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;import com.tutorialspoint.StudentJDBCTemplate;public class MainApp {   public static void main(String[] args) {      ApplicationContext context = new ClassPathXmlApplicationContext("Beans.xml");      StudentJDBCTemplate studentJDBCTemplate =          (StudentJDBCTemplate)context.getBean("studentJDBCTemplate");      System.out.println("------Records Creation--------" );      studentJDBCTemplate.create("Zara", 11);      studentJDBCTemplate.create("Nuha", 2);      studentJDBCTemplate.create("Ayan", 15);      System.out.println("------Listing Multiple Records--------" );      List<Student> students = studentJDBCTemplate.listStudents();      for (Student record : students) {         System.out.print("ID : " + record.getId() );         System.out.print(", Name : " + record.getName() );         System.out.println(", Age : " + record.getAge());      }      System.out.println("----Updating Record with ID = 2 -----" );      studentJDBCTemplate.update(2, 20);      System.out.println("----Listing Record with ID = 2 -----" );      Student student = studentJDBCTemplate.getStudent(2);      System.out.print("ID : " + student.getId() );      System.out.print(", Name : " + student.getName() );      System.out.println(", Age : " + student.getAge());   }}

7 Following is the configuration file Beans.xml 配置

<?xml version = "1.0" encoding = "UTF-8"?><beans xmlns = "http://www.springframework.org/schema/beans"   xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"    xsi:schemaLocation = "http://www.springframework.org/schema/beans   http://www.springframework.org/schema/beans/spring-beans-3.0.xsd ">   <!-- Initialization for data source -->   <bean id="dataSource"       class = "org.springframework.jdbc.datasource.DriverManagerDataSource">      <property name = "driverClassName" value = "com.mysql.jdbc.Driver"/>      <property name = "url" value = "jdbc:mysql://localhost:3306/TEST"/>      <property name = "username" value = "root"/>      <property name = "password" value = "password"/>   </bean>   <!-- Definition for studentJDBCTemplate bean -->   <bean id = "studentJDBCTemplate"       class = "com.tutorialspoint.StudentJDBCTemplate">      <property name = "dataSource" ref = "dataSource" />       </bean></beans>

8 运行结果

------Records Creation--------Created Record Name = Zara Age = 11Created Record Name = Nuha Age = 2Created Record Name = Ayan Age = 15------Listing Multiple Records--------ID : 1, Name : Zara, Age : 11ID : 2, Name : Nuha, Age : 2ID : 3, Name : Ayan, Age : 15----Updating Record with ID = 2 -----Updated Record with ID = 2----Listing Record with ID = 2 -----ID : 2, Name : Nuha, Age : 20