Spring中的SQL儲存過程

SimpleJdbcCall類可用於呼叫具有輸入和輸出引數的儲存過程。在使用Apache Derby、DB2、MySQL、Microsoft SQL Server、Oracle和Sybase等任何RDBMS時，都可以使用此方法。

為了理解這種方法，讓我們以Student表為例，它可以用以下DDL在MySQL TEST資料庫中建立：

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

接下來，考慮以下MySQL儲存過程，它接收學生ID並使用OUT引數返回相應學生的姓名和年齡。因此，讓我們使用MySQL命令提示符在您的TEST資料庫中建立此儲存過程：

DELIMITER $$

DROP PROCEDURE IF EXISTS `TEST`.`getRecord` $$
CREATE PROCEDURE `TEST`.`getRecord` (
IN in_id INTEGER,
OUT out_name VARCHAR(20),
OUT out_age  INTEGER)
BEGIN
   SELECT name, age
   INTO out_name, out_age
   FROM Student where id = in_id;
END $$

DELIMITER ;

現在讓我們編寫Spring JDBC應用程式，它將在我們的Student表上實現簡單的建立和讀取操作。讓我們準備好一個可執行的Eclipse IDE，並按照以下步驟建立一個Spring應用程式：

以下是資料訪問物件介面檔案StudentDAO.java的內容

package com.tutorialspoint;

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();
}

以下是Student.java檔案的內容

package com.tutorialspoint;

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;
   }
}

以下是StudentMapper.java檔案的內容

package com.tutorialspoint;

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;
   }
}

以下是為已定義的DAO介面StudentDAO編寫的實現類檔案StudentJDBCTemplate.java：

package com.tutorialspoint;

import java.util.Map;

import javax.sql.DataSource;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.namedparam.MapSqlParameterSource;
import org.springframework.jdbc.core.namedparam.SqlParameterSource;
import org.springframework.jdbc.core.simple.SimpleJdbcCall;

public class StudentJDBCTemplate implements StudentDAO {
   private DataSource dataSource;
   private SimpleJdbcCall jdbcCall;

   public void setDataSource(DataSource dataSource) {
      this.dataSource = dataSource;
      this.jdbcCall =  new SimpleJdbcCall(dataSource).withProcedureName("getRecord");
   }
   public void create(String name, Integer age) {
      JdbcTemplate jdbcTemplateObject = new JdbcTemplate(dataSource);
      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) {
      SqlParameterSource in = new MapSqlParameterSource().addValue("in_id", id);
      Map<String, Object> out = jdbcCall.execute(in);

      Student student = new Student();
      student.setId(id);
      student.setName((String) out.get("out_name"));
      student.setAge((Integer) out.get("out_age"));
      return student;
   }
   public List<Student> listStudents() {
      String SQL = "select * from Student";
      List <Student> students = jdbcTemplateObject.query(SQL, new StudentMapper());
      return students;
   }
}

關於上述程式的一些說明：您為執行呼叫編寫的程式碼涉及建立包含輸入引數的SqlParameterSource。重要的是將為輸入值提供的名稱與儲存過程中宣告的引數名稱相匹配。execute方法獲取輸入引數並返回一個Map，其中包含任何以儲存過程中指定的名稱為鍵的輸出引數。現在讓我們繼續使用主應用程式檔案MainApp.java，如下所示：

package com.tutorialspoint;

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("----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());
   }
}

以下是配置檔案Beans.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" 
   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://: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>

建立原始檔和bean配置檔案後，讓我們執行應用程式。如果您的應用程式一切正常，它將列印以下訊息：

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