iBATIS更新操作
上一章展示瞭如何使用iBATIS對錶進行讀取操作。本章將告訴你如何在一個表中使用iBATIS更新記錄。
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) );
此表有如下只有一條記錄：
mysql> select * from EMPLOYEE; +----+------------+-----------+--------+ | id | first_name | last_name | salary | +----+------------+-----------+--------+ | 1 | Zara | Ali | 5000 | +----+------------+-----------+--------+ 1 row in set (0.00 sec)
Employee POJO 類:
要執行UDPATE操作，需要修改Employee.java文件，如下所示：
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 文件:
要定義使用iBATIS SQL映射語句，我們想補充的
<sqlMap namespace="Employee"> <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 <select id="getAll" resultClass="Employee"> SELECT * FROM EMPLOYEE <update id="update" parameterClass="Employee"> UPDATE EMPLOYEE
SET first_name = #first_name#
WHERE id = #id#
IbatisUpdate.java 文件:
文件將應用程序級別的邏輯來更新記錄到Employee表：
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 IbatisUpdate{ public static void main(String[] args) throws IOException,SQLException{ Reader rd = Resources.getResourceAsReader("SqlMapConfig.xml"); SqlMapClient smc = SqlMapClientBuilder.buildSqlMapClient(rd); /* This would update one record in Employee table. */ System.out.println("Going to update record....."); Employee rec = new Employee(); rec.setId(1); rec.setFirstName( "Roma"); smc.update("Employee.update", rec ); System.out.println("Record updated Successfully "); System.out.println("Going to read records....."); List <Employee> ems = (List<Employee>) smc.queryForList("Employee.getAll", null); Employee em = null; for (Employee e : ems) { System.out.print(" " + e.getId()); System.out.print(" " + e.getFirstName()); System.out.print(" " + e.getLastName()); System.out.print(" " + e.getSalary()); em = e; System.out.println(""); } System.out.println("Records Read Successfully "); } }
編譯和運行：
下面是步驟來編譯並運行上述軟件。請確保您已在進行的編譯和執行之前，適當地設置PATH和CLASSPATH。
創建Employee.xml如上所示。
創建Employee.java如上圖所示，並編譯它。
創建IbatisUpdate.java如上圖所示，並編譯它。
執行IbatisUpdate二進制文件來運行程序。
得到下面的結果，並創建紀錄在EMPLOYEE表進行更新和更高版本相同的記錄將從EMPLOYEE表中讀出。
Going to update record..... Record updated Successfully Going to read records..... 1 Roma Ali 5000 Records Read Successfully