一个简单的 iBatis 实现——完整示例

表和数据：

CREATE TABLE weather (
    city            varchar(80),
    temp_lo         int,           -- low temperature
    temp_hi         int,           -- high temperature
    prcp            real,          -- average temperature
    date            date
);

insert into weather values ('Wuhan', 15, 30, 25.5, '2011-09-21');
insert into weather values ('Beijing', 10, 22, 15.3, '2011-09-22');
insert into weather values ('Shanghai', 17, 35, 28.6, '2011-09-22');
insert into weather values ('Guangzhou', 30, 36, 32.7, '2011-09-22');
insert into weather values ('Xiamen', 24, 32, 30.3, '2011-09-22');

文件目录及说明：

配置文件，WeatherRecord.xml，描述操作细节

<?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="WeatherRecord">

  <!-- Use type aliases to avoid typing the full classname every time. -->
  <typeAlias alias="WeatherRecord" type="com.gq.ibatis.WeatherRecord"/>

  <!-- Result maps describe the mapping between the columns returned
       from a query, and the class properties.  A result map isn't
       necessary if the columns (or aliases) match to the properties 
       exactly. -->
  <resultMap id="WeatherResult" class="WeatherRecord">
    <result property="city" column="city"/>
    <result property="lowTemperature" column="temp_lo"/>
    <result property="highTemperature" column="temp_hi"/>
    <result property="avgTemperature" column="prcp"/>
    <result property="date" column="date"/>
  </resultMap>

  <!-- Select with no parameters using the result map for WeatherResult class. -->
  <select id="selectAllWeatherRecords" resultMap="WeatherResult">
    select * from weather
  </select>

  <!-- A simpler select example with the result map. Using the String parameter class -->
  <select id="selectWeatherRecordByCity" parameterClass="String" resultMap="WeatherResult">
    select * from weather where city = #city#
  </select>
   
  <!-- Insert example, using the WeatherResult parameter class -->
  <insert id="insertWeatherRecord" parameterClass="WeatherRecord">
    insert into weather (
      city,
      temp_lo,
      temp_hi,
      prcp,
      date
    )values (
      #city#, #lowTemperature#, #highTemperature#, #avgTemperature#, #date#
    )
  </insert>

  <!-- Update example, using the WeatherResult parameter class -->
  <update id="updateWeatherRecord" parameterClass="WeatherRecord">
    update weather set
      city = #city#,
      temp_lo = #lowTemperature#,
      temp_hi = #highTemperature#,
      prcp = #avgTemperature#,
      date = #date#
    where
      city = #city#
  </update>

  <!-- Delete example, using an String as the parameter class -->
  <delete id="deleteWeatherRecordByCity" parameterClass="String">
    delete from weather where city = #city#
  </delete>

</sqlMap>

配置文件，SqlMapConfig.xml ，描述整体

<?xml version="1.0" encoding="UTF-8" ?>

<!DOCTYPE sqlMapConfig      
    PUBLIC "-//ibatis.apache.org//DTD SQL Map Config 2.0//EN"      
    "http://ibatis.apache.org/dtd/sql-map-config-2.dtd">

<sqlMapConfig>

  <!-- Configure a built-in transaction manager.  If you're using an 
       app server, you probably want to use its transaction manager 
       and a managed datasource -->
  <transactionManager type="JDBC">
    <dataSource type="SIMPLE">
      <property name="JDBC.Driver" value="org.postgresql.Driver"/>
      <property name="JDBC.ConnectionURL" value="jdbc:postgresql://localhost:5432/testdb"/>
      <property name="JDBC.Username" value="postgres"/>
      <property name="JDBC.Password" value="postgres"/>
    </dataSource>
  </transactionManager>

  <!-- List the SQL Map XML files. They can be loaded from the 
       classpath, as they are here (com.domain.data...) -->
  <sqlMap resource="com/gq/ibatis/WeatherRecord.xml"/>
  <!-- List more here...
  <sqlMap resource="com/mydomain/data/Order.xml"/>
  <sqlMap resource="com/mydomain/data/Documents.xml"/>
  -->

</sqlMapConfig>

JavaBean 类 WeatherRecord.java

注意：数据库中的 date 为 date类型，则Java 中对应为 java.sql.Date ！

不能改为 String 类型，会映射出错。

/**
*Create Date	:2011-9-22
*Create User	:GongQiang
*Modify Status	:
*File Location 	$Archive:Test-WebService/com.gq.ibatis/WeatherRecord.java$
*Last Modify	$Author:  $
*Modify Date	$Date: $
*Now Revision 	$Revision: $
*
*Copyright (c) 2004 Sino-Japanese Engineering Corp, Inc. All Rights Reserved.
*/

package com.gq.ibatis;

import java.sql.Date;

public class WeatherRecord {
	private String city;
	private int lowTemperature;
	private int highTemperature;
	private float avgTemperature;
	private Date date;
	
	public String getCity() {
		return city;
	}
	public void setCity(String city) {
		this.city = city;
	}
	public int getLowTemperature() {
		return lowTemperature;
	}
	public void setLowTemperature(int lowTemperature) {
		this.lowTemperature = lowTemperature;
	}
	public int getHighTemperature() {
		return highTemperature;
	}
	public void setHighTemperature(int highTemperature) {
		this.highTemperature = highTemperature;
	}
	public float getAvgTemperature() {
		return avgTemperature;
	}
	public void setAvgTemperature(float avgTemperature) {
		this.avgTemperature = avgTemperature;
	}
	public Date getDate() {
		//DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
		//return dateFormat.format(date);
		return date;
	}
	public void setDate(Date date) {
		this.date = date;
	}

}

操作类，SimpleExample.java

package com.gq.ibatis;

import com.ibatis.sqlmap.client.SqlMapClient;
import com.ibatis.sqlmap.client.SqlMapClientBuilder;
import com.ibatis.common.resources.Resources;

import java.io.Reader;
import java.io.IOException;
import java.util.List;
import java.sql.SQLException;

/**
 * This is not a best practices class. It's just an example to give you an idea
 * of how iBATIS works. For a more complete example, see JPetStore 5.0 at
 * http://www.ibatis.com.
 */
public class SimpleExample {

	/**
	 * SqlMapClient instances are thread safe, so you only need one. In this
	 * case, we'll use a static singleton. So sue me. ;-)
	 */
	private static SqlMapClient sqlMapper;

	/**
	 * It's not a good idea to put code that can fail in a class initializer,
	 * but for sake of argument, here's how you configure an SQL Map.
	 */
	static {
		try {
			Reader reader = Resources.getResourceAsReader("com/gq/ibatis/SqlMapConfig.xml");
			sqlMapper = SqlMapClientBuilder.buildSqlMapClient(reader);
			reader.close();
		} catch (IOException e) {
			// Fail fast.
			throw new RuntimeException("Something bad happened while building the SqlMapClient instance."+ e, e);
		}
	}

	@SuppressWarnings("unchecked")
	/** It is safe cast, because list contain just WeatherRecord **/
	public static List<WeatherRecord> selectAllWeatherRecords() throws SQLException {
		return (List<WeatherRecord>) sqlMapper.queryForList("selectAllWeatherRecords");
	}

	public static WeatherRecord selectWeatherRecordByCity(String city)throws SQLException {
		return (WeatherRecord) sqlMapper.queryForObject("selectWeatherRecordByCity", city);
	}

	public static void insertWeatherRecord(WeatherRecord WeatherRecord)throws SQLException {
		sqlMapper.insert("insertWeatherRecord", WeatherRecord);
	}

	public static void updateWeatherRecord(WeatherRecord WeatherRecord)throws SQLException {
		sqlMapper.update("updateWeatherRecord", WeatherRecord);
	}

	public static void deleteWeatherRecordByCity(String city) throws SQLException {
		sqlMapper.delete("deleteWeatherRecordByCity", city);
	}

}

测试类，TestIbatis.java 和输出的结果

/**
*Create Date	:2011-9-22
*Create User	:GongQiang
*Modify Status	:
*File Location 	$Archive:Test-WebService/com.gq.ibatis/TestIbatis.java$
*Last Modify	$Author:  $
*Modify Date	$Date: $
*Now Revision 	$Revision: $
*
*Copyright (c) 2004 Sino-Japanese Engineering Corp, Inc. All Rights Reserved.
*/

package com.gq.ibatis;

import java.sql.SQLException;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.List;

public class TestIbatis {

	public static void main(String[] args) throws SQLException {
		testSelectAll();
		testSelectByCity();
		
		testInsert();
		System.out.println("---- After insert ----");
		testSelectAll();
		
		testUpdate();
		System.out.println("---- After update ----");
		testSelectAll();
		
		testDeleteByCity();
		System.out.println("---- After delete ----");
		testSelectAll();

	}
	
	/** 查询所有*/
	private static void testSelectAll() throws SQLException{
		List<WeatherRecord> weatherRecords = null;
		weatherRecords = SimpleExample.selectAllWeatherRecords();
		for( WeatherRecord wr : weatherRecords ){
			System.out.print( wr.getCity() + "\t" );
			System.out.print( wr.getLowTemperature() + "\t" );
			System.out.print( wr.getHighTemperature() + "\t" );
			System.out.print( wr.getAvgTemperature() + "\t" );
			System.out.println( wr.getDate() + "\t" );
		}
	}
	
	/** 根据城市名查询**/
	private static void testSelectByCity() throws SQLException{
		WeatherRecord wr = SimpleExample.selectWeatherRecordByCity("Beijing");
		System.out.println("Find record by city: "+ wr.getCity());
		System.out.print( wr.getCity() + "\t");
		System.out.print( wr.getLowTemperature() + "\t");
		System.out.print( wr.getHighTemperature() + "\t");
		System.out.print( wr.getAvgTemperature() + "\t");
		System.out.println( wr.getDate());
	}
	
	/** 插入操作**/
	private static void testInsert() throws SQLException{
		WeatherRecord wr = new WeatherRecord();
		wr.setCity( "Changchun" );
		wr.setLowTemperature( 5 );
		wr.setHighTemperature( 15 );
		wr.setAvgTemperature( 8.6f );
		wr.setDate( parseDate("2011-09-22") );
		
		SimpleExample.insertWeatherRecord(wr);
	}
	
	private static java.sql.Date parseDate( String dateStr ){
		DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
		try {
			return new java.sql.Date(dateFormat.parse( dateStr ).getTime());
		} catch (ParseException e) {
			e.printStackTrace();
		}
		return null;
	}
	
	/** 更新操作**/
	private static void testUpdate() throws SQLException{
		WeatherRecord wr = new WeatherRecord();
		wr.setCity( "Changchun" );
		wr.setLowTemperature( 5 );
		wr.setHighTemperature( 15 );
		wr.setAvgTemperature( 8.6f );
		wr.setDate( parseDate("2012-01-01") );
		
		SimpleExample.updateWeatherRecord(wr);
	}
	
	private static void testDeleteByCity() throws SQLException{
		SimpleExample.deleteWeatherRecordByCity( "Changchun" );
	}

}

运行结果：