iBATIS儲存過程


使用iBATIS組態來呼叫儲存過程。為了理解這一章,首先需要了解我們是如何在MySQL中建立一個儲存過程。

在繼續對本章學習之前,可以通過MySQL儲存過程。 

我們已經在MySQL下有EMPLOYEE表:

CREATE TABLE EMPLOYEE (
   id INT NOT NULL auto_increment,
   first_name VARCHAR(20) default NULL,
   last_name  VARCHAR(20) default NULL,
   salary     INT  default NULL,
   PRIMARY KEY (id)
);

讓我們在MySQL資料庫中建立以下儲存過程。

DELIMITER $$

DROP PROCEDURE IF EXISTS `testdb`.`getEmp` $$
CREATE PROCEDURE `testdb`.`getEmp` 
   (IN empid INT)
BEGIN
   SELECT * FROM EMPLOYEE
   WHERE ID = empid;
END $$

DELIMITER;

考慮EMPLOYEE表是有兩條記錄如下:

mysql> select * from EMPLOYEE;
+----+------------+-----------+--------+
| id | first_name | last_name | salary |
+----+------------+-----------+--------+
|  1 | Zara       | Ali       |   5000 |
|  2 | Roma       | Ali       |   3000 |
+----+------------+-----------+--------+
2 row in set (0.00 sec)

Employee POJO 類:

使用儲存過程,你就需要修改Employee.java檔案。因此,讓我們保持它,因為它是在前一章。

public class Employee {
  private int id;
  private String first_name; 
  private String last_name;   
  private int salary;  

  /* Define constructors for the Employee class. */
  public Employee() {}
  
  public Employee(String fname, String lname, int salary) {
    this.first_name = fname;
    this.last_name = lname;
    this.salary = salary;
  }

 /* Here are the required method definitions */
  public int getId() {
    return id;
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getFirstName() {
    return first_name;
  }
  public void setFirstName(String fname) {
    this.first_name = fname;
  }
  public String getLastName() {
    return last_name;
  }
  public void setlastName(String lname) {
    this.last_name = lname;
  }
  public int getSalary() {
    return salary;
  }
  public void setSalary(int salary) {
    this.salary = salary;
  }

 } /* End of Employee */

Employee.xml 類:

在這裡,我們將修改Employee.xml檔案介紹<procedure></procedure>和<parameterMap></parameterMap>標記。這裡<procedure></procedure>標籤將有一個id,我們會用我們的應用程式來呼叫儲存過程。

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sqlMap 
PUBLIC "-//ibatis.apache.org//DTD SQL Map 2.0//EN"
"http://ibatis.apache.org/dtd/sql-map-2.dtd">

<sqlMap namespace="Employee">

<!-- Perform Insert Operation -->
<insert id="insert" parameterClass="Employee">
   INSERT INTO EMPLOYEE(first_name, last_name, salary)
   values (#first_name#, #last_name#, #salary#)

   <selectKey resultClass="int" keyProperty="id">
      select last_insert_id() as id
   </selectKey>

</insert>

<!-- Perform Read Operation -->
<select id="getAll" resultClass="Employee">
   SELECT * FROM EMPLOYEE
</select>

<!-- Perform Update Operation -->
<update id="update" parameterClass="Employee">
   UPDATE EMPLOYEE
   SET    first_name = #first_name#
   WHERE  id = #id#
</update>

<!-- Perform Delete Operation -->
<delete id="delete" parameterClass="int">
   DELETE FROM EMPLOYEE
   WHERE  id = #id#
</delete>

<!-- To call stored procedure. -->
<procedure id="getEmpInfo" resultClass="Employee"
              parameterMap="getEmpInfoCall">
   { call getEmp( #acctID# ) } 
</procedure>
<parameterMap id="getEmpInfoCall" class="map">
   <parameter property="acctID" jdbcType="INT" 
   javaType="java.lang.Integer" mode="IN"/>
</parameterMap>

</sqlMap>

IbatisSP.java 檔案:

檔案將應用程式級別的邏輯讀取使用結果對映Employee表員工的姓名name:

import com.ibatis.common.resources.Resources;
import com.ibatis.sqlmap.client.SqlMapClient;
import com.ibatis.sqlmap.client.SqlMapClientBuilder;
import java.io.*;
import java.sql.SQLException;
import java.util.*;

public class IbatisSP{
  public static void main(String[] args)
   throws IOException,SQLException{
   Reader rd = Resources.getResourceAsReader("SqlMapConfig.xml");
   SqlMapClient smc = SqlMapClientBuilder.buildSqlMapClient(rd);

   int id = 1;
   System.out.println("Going to read employee name.....");
   Employee e = (Employee)smc.queryForObject
                ("Employee.getEmpInfo", id);

   System.out.println("First Name:  " + e.getFirstName());

   System.out.println("Record name Successfully ");

  }
} 

編譯和執行:

下面是步驟來編譯並執行上述應用程式。請確保您在進行的編譯和執行之前,適當地設定PATH和CLASSPATH。

  • 建立Employee.xml如上所示。

  • 建立Employee.java如上圖所示,並編譯它。

  • 建立IbatisSP.java如上圖所示,並編譯它。

  • 執行IbatisSP二進位制檔案來執行程式。

得到以下結果:

Going to read record.....
ID:  1
First Name:  Zara
Last Name:  Ali
Salary:  5000
Record read Successfully