JdbcTemplate系列(二)----实战CRUD

第一步:创建Maven

eclipse新建Mavne选择Maven Project项目

选择Maven-archetype-webapp

输入Group id和Artifact id

输入好之后,点击Finsh,项目创建如下

查看index.jsp文件

发现报servlet错,这是由于缺少servlet.api所导致的,在pom.xml加入引用就可以了。

第二步:编辑POM文件

然后项目右键"Build path"选择ALLow output...

会发现项目多出来了几个目录,如下:

在pom.xml文件中加入以下内容:

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.fendo.com</groupId>
  <artifactId>JDBC</artifactId>
  <packaging>war</packaging>
  <version>0.0.1-SNAPSHOT</version>
  <name>JDBC Maven Webapp</name>
  <url>http://maven.apache.org</url>

     <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

        <spring-version>4.1.2.RELEASE</spring-version>
        <commons.version>1.4</commons.version>
        <c3p0.version>0.9.1.2</c3p0.version>
        <log4j.version>1.2.17</log4j.version>
        <servlet.api.version>2.5</servlet.api.version>
        <jstl.version>1.2</jstl.version>
        <jsp.api.version>2.1</jsp.api.version>
    </properties>

  <dependencies>
<!-- https://mvnrepository.com/artifact/junit/junit -->
<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.12</version>
</dependency>

    <dependency>
         <groupId>commons-dbcp</groupId>
         <artifactId>commons-dbcp</artifactId>
         <version>${commons.version}</version>
     </dependency>


     <!-- SPRING JDBC -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>${spring-version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring-version}</version>
        </dependency>


        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>${spring-version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring-version}</version>
        </dependency>
        <dependency>
            <groupId>c3p0</groupId>
            <artifactId>c3p0</artifactId>
            <version>${c3p0.version}</version>
        </dependency>

        <dependency>
            <groupId>javax.transaction</groupId>
            <artifactId>transaction-api</artifactId>
            <version>1.1</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.34</version>
        </dependency>

        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.7.4</version>
        </dependency>


        <!-- jsp/servlet support -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>${servlet.api.version}</version>
            <type>jar</type>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>${jstl.version}</version>
            <type>jar</type>
        </dependency>
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>jsp-api</artifactId>
            <version>${jsp.api.version}</version>
            <type>jar</type>
</dependency>


       <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>${log4j.version}</version>
        </dependency>



        <!-- SPRING JDBC -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>${spring-version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring-version}</version>
        </dependency>


        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>${spring-version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring-version}</version>
        </dependency>
        <dependency>
            <groupId>c3p0</groupId>
            <artifactId>c3p0</artifactId>
            <version>${c3p0.version}</version>
        </dependency>

        <dependency>
            <groupId>javax.transaction</groupId>
            <artifactId>transaction-api</artifactId>
            <version>1.1</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.34</version>
        </dependency>

        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.7.4</version>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
        </dependency>
  </dependencies>
  <build>
    <finalName>JDBC</finalName>
  </build>
</project>

第三步:编辑web.xml、jdbc.properties、appliactionContext.xml文件

修改web.xml如下:

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

<web-app>
  <display-name>Archetype Created Web Application</display-name>

  <listener>
    <listener-class>org.springframework.web.util.IntrospectorCleanupListener</listener-class>
  </listener>

  <servlet>
    <servlet-name>spring</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:*appliactionContext.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>

  <servlet-mapping>
    <servlet-name>spring</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

  <filter>
    <filter-name>setCharacter</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <init-param>
      <param-name>encoding</param-name>
      <param-value>utf-8</param-value>
    </init-param>
  </filter>

  <filter-mapping>
    <filter-name>setCharacter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

</web-app>

在src\main\resources下面新建一个属性配置文件: jdbc.properties

jdbc.user=root
jdbc.password=root
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.jdbcUrl=jdbc:mysql://127.0.0.1:3306/jdbc
jdbc.initPoolSize=5
jdbc.maxPoolSize=10

新建Spring配置文件applicationContext.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"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.1.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.1.xsd">

    <!-- 基于注解的，导入标识的包,可以识别本包，或其自包,其只对带有指定注解的类，方法有效，不是对这个包中的所有类和方法有效 -->
    <context:component-scan base-package="com.fendo.dao"></context:component-scan>


<context:property-placeholder location="classpath:jdbc.properties"/>  



    <!-- 配置c3p0数据源 -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="user" value="${jdbc.user}"></property>
        <property name="password" value="${jdbc.password}"></property>
        <property name="driverClass" value="${jdbc.driverClass}"></property>
        <property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>

        <property name="initialPoolSize" value="${jdbc.initPoolSize}"></property>
        <property name="maxPoolSize" value="${jdbc.maxPoolSize}"></property>
    </bean>



    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="dataSource"></property>
    </bean>


    <bean id="userDao" class="com.fendo.impl.UserDaoImpl">
        <property name="jdbcTemplate" ref="jdbcTemplate"></property>
    </bean>

    <!-- 配置NamedParameterJdbcTemplate,该对象可以使用具名参数，其没有无参的构造器，所以必须为其构造器指定参数 -->  
<bean id="namedParameterJdbcTemplate"  
    class="org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate">  
    <constructor-arg ref="dataSource"></constructor-arg>  
</bean>

</beans>

新建好之后如下:

第四步:新建实体类与测试方法

对应的SQL文件为:

CREATE TABLE `student` (
  `sid` int(11) NOT NULL AUTO_INCREMENT,
  `sname` varchar(255) DEFAULT NULL,
  `sage` varchar(255) DEFAULT NULL,
  `ssex` varchar(255) DEFAULT NULL,
  PRIMARY KEY (`sid`)
) ENGINE=InnoDB AUTO_INCREMENT=44 DEFAULT CHARSET=utf8;

新建UserDao类:

package com.fendo.dao;


import java.util.List;

import com.fendo.entity.User;

public interface UserDao {

    public void addUser(User user);

    public void deleteUser(int id);

    public void updateUser(User user);

    public String searchUserName(int id);

    public User searchUser(int id);

    public List<User> findAll();

}

建立类：UserDaoAnnotation，基于注解的查询方法

package com.fendo.dao;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.stereotype.Component;

import com.fendo.entity.User;

@Component//基本注解
public class UserDaoAnnotation {

    @Autowired
    public JdbcTemplate jdbcTemplate;

    public User get(Integer sid){
        String sql="select sid,sname,ssex from student where sid=?";
        RowMapper<User> rowMapper=new BeanPropertyRowMapper<User>(User.class);
        User user=jdbcTemplate.queryForObject(sql, rowMapper, sid);
        return user;
    }
}

实现RowMapper接口

package com.fendo.dao;

import java.sql.ResultSet;
import java.sql.SQLException;

import org.springframework.jdbc.core.RowMapper;

import com.fendo.entity.User;

public class UserRowMapper implements RowMapper<User>{

public User mapRow(ResultSet rs, int rowNum) throws SQLException {
    // rs 已经指向每一条数据，不需要自己调用 next，将rs指向数据 转换 User对象
User user = new User();
user.setSid(rs.getString("sid"));
user.setSname(rs.getString("sname"));
return user;
}

}

创建User实体类:

package com.fendo.entity;

public class User {

private String sid;
private String sname;
private String sage;
private String ssex;
public String getSid() {
return sid;
}
public void setSid(String sid) {
this.sid = sid;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public String getSage() {
return sage;
}
public void setSage(String sage) {
this.sage = sage;
}
public String getSsex() {
return ssex;
}
public void setSsex(String ssex) {
this.ssex = ssex;
}
}

创建实现类:

package com.fendo.impl;

import java.util.List;

import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.support.JdbcDaoSupport;

import com.fendo.dao.UserDao;
import com.fendo.dao.UserRowMapper;
import com.fendo.entity.User;


public class UserDaoImpl extends JdbcDaoSupport implements UserDao{

public void addUser(User user) {
        String sql = "insert into student values(?,?,?,?)";
        this.getJdbcTemplate().update(sql, user.getSid(), user.getSname(),
                user.getSage(),user.getSsex());
    }

    public void deleteUser(int id) {
        String sql = "delete from student where sid=?";
        this.getJdbcTemplate().update(sql, id);

    }

    public void updateUser(User user) {
        String sql = "update student set sname=?,sage=? where sid=?";
        this.getJdbcTemplate().update(sql, user.getSname(),
                user.getSage(), user.getSid());
    }

    public String searchUserName(int sid) {// 简单查询，按照ID查询，返回字符串
        String sql = "select sname from student where sid=?";
        // 返回类型为String(String.class)
        return this.getJdbcTemplate().queryForObject(sql, String.class, sid);

    }

    public List<User> findAll() {// 复杂查询返回List集合
        String sql = "select * from student";
        return this.getJdbcTemplate().query(sql, new UserRowMapper());

    }

    public User searchUser(int id) {
        String sql="select * from student where sid=?";
        return this.getJdbcTemplate().queryForObject(sql, new UserRowMapper(), id);
    }

}

测试类1:

package com.fendo.test;


import java.util.List;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.fendo.dao.UserDao;
import com.fendo.entity.User;

public class Temp {

@Test//增
    public void demo1(){
        User user=new User();
        user.setSid("3");
        user.setSname("admin");
        user.setSage("18");

        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("appliactionContext.xml");
        UserDao dao=(UserDao) applicationContext.getBean("userDao");
        dao.addUser(user);

    }

    @Test//改
    public void demo2(){
        User user=new User();
        user.setSid("3");
        user.setSname("fendo");
        user.setSage("18");

        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("appliactionContext.xml");
        UserDao dao=(UserDao) applicationContext.getBean("userDao");
        dao.updateUser(user);
    }

    @Test//删
    public void demo3(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("appliactionContext.xml");
        UserDao dao=(UserDao) applicationContext.getBean("userDao");
        dao.deleteUser(3);
    }

    @Test//查（简单查询，返回字符串）
    public void demo4(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("appliactionContext.xml");
        UserDao dao=(UserDao) applicationContext.getBean("userDao");
        String name=dao.searchUserName(3);
        System.out.println(name);
    }

    @Test//查（简单查询，返回对象）
    public void demo5(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("appliactionContext.xml");
        UserDao dao=(UserDao) applicationContext.getBean("userDao");
        User user=dao.searchUser(3);
        System.out.println(user.getSname());
    }

    @Test//查（复杂查询，返回对象集合）
    public void demo6(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("appliactionContext.xml");
        UserDao dao=(UserDao) applicationContext.getBean("userDao");
        List<User> users=dao.findAll();
        System.out.println(users.size());
    }
}

测试类2:

package com.fendo.test;


import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.sql.DataSource;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.namedparam.BeanPropertySqlParameterSource;
import org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate;
import org.springframework.jdbc.core.namedparam.SqlParameterSource;

import com.fendo.dao.UserDao;
import com.fendo.dao.UserDaoAnnotation;
import com.fendo.entity.User;
import com.fendo.impl.UserDaoImpl;

public class Temp1 {

    private ApplicationContext ctx=null;
    private JdbcTemplate jdbcTemplate;
    private UserDaoAnnotation userDaoAnnotation;

    private NamedParameterJdbcTemplate namedParameterJdbcTemplate;
    {
        ctx=new ClassPathXmlApplicationContext("appliactionContext.xml");
        jdbcTemplate=(JdbcTemplate)ctx.getBean("jdbcTemplate");
        userDaoAnnotation=ctx.getBean(UserDaoAnnotation.class);
        namedParameterJdbcTemplate=ctx.getBean(NamedParameterJdbcTemplate.class);
    }


    /**
 　　* 使用具名参数时, 可以使用 update(String sql, SqlParameterSource paramSource) 方法进行更新操作
 　　* 1. SQL 语句中的参数名和类的属性一致!即上边employee中属性一致
 　　* 2. 使用 SqlParameterSource 的 BeanPropertySqlParameterSource 实现类作为参数. 
 　　*/
    @Test
    public void testNamedParameterJdbcTemplate2(){
    String sql="insert into student(sname,sage,ssex) values(:sname,:sage,:ssex)";
    User user=new User();
user.setSname("fendo");
user.setSage("18");
user.setSsex("男");
SqlParameterSource paramSource=new BeanPropertySqlParameterSource(user);
namedParameterJdbcTemplate.update(sql,paramSource);
    }


//可以为参数起名字
//好处: 若有多个参数, 则不用再去对应位置, 直接对应参数名, 便于维护
//缺点: 较为麻烦.
        @Test
public void testNamedParameterJdbcTemplate(){
String sql="insert into student(sname,sage,ssex) values(:sname,:sage,:ssex)";
Map<String, Object> paramMap=new HashMap();
paramMap.put("sname", "fendo");
paramMap.put("sage", "18");
paramMap.put("ssex", "男");
namedParameterJdbcTemplate.update(sql, paramMap);
}




     //对基于注解的方法测试
     @Test
     public void tesUserDao(){
         System.out.println(userDaoAnnotation.get(2));
     }


     //获取单个列的值, 或做统计查询
     //使用 queryForObject(String sql, Class<Long> requiredType)
    @Test
     public void testQueryForObject2(){
         String sql="select count(sid) from student";
         long count=jdbcTemplate.queryForObject(sql, Long.class);
         System.out.println(count);
     }

     //查到实体类的集合
     //注意调用的不是 queryForList 方法
     @Test
     public void testQueryForList(){
         String sql="select sid,sname,sage from student where sid>?";
         RowMapper<User> rowMapper=new BeanPropertyRowMapper<User>(User.class);
         List<User> user=jdbcTemplate.query(sql, rowMapper, 1);

         System.out.println(user);
     }

     /**
      * 从数据库中获取一条记录, 实际得到对应的一个对象
      * 注意不是调用 queryForObject(String sql, Class<Employee> requiredType, Object... args) 方法!
      * 而需要调用 queryForObject(String sql, RowMapper<Employee> rowMapper, Object... args)
      * 1. 其中的 RowMapper 指定如何去映射结果集的行, 常用的实现类为 BeanPropertyRowMapper
      * 2. 使用 SQL 中列的别名完成列名和类的属性名的映射. 例如 last_name lastName
      * 3. 不支持级联属性. JdbcTemplate 到底是一个 JDBC 的小工具, 而不是 ORM 框架
      */
     @Test
     public void testQueryForObject(){

     // String sql="select id,last_name lastName,email,dept_id as \"department.id\" from tables where id=?";
         String sql="select sid,sname,sage,ssex as \"department.sex\" from student where sid=?";

         RowMapper<User> rowMapper=new BeanPropertyRowMapper<User>(User.class);
         User employee=jdbcTemplate.queryForObject(sql, rowMapper,1);

         System.out.println(employee);
     }

     //执行批量更新: 批量的 INSERT, UPDATE, DELETE
     //最后一个参数是 Object[] 的 List 类型: 因为修改一条记录需要一个 Object 的数组, 
     //那么多条不就需要多个 Object 的数组
     @Test
     public void testBatchUpdate(){
         String sql="insert into student(sid,sname,sage) values(?,?,?)";

         List<Object[]> batchArgs=new ArrayList<Object[]>();

         batchArgs.add(new Object[]{"11","fendo","15"});
         batchArgs.add(new Object[]{"21","ckse","16"});
         batchArgs.add(new Object[]{"31","gogo","17"});
         batchArgs.add(new Object[]{"41","asde","18"});

         jdbcTemplate.batchUpdate(sql,batchArgs);
     }

     //执行 INSERT, UPDATE, DELETE，只修改sql语句，即可
     @Test
     public void testUpdate(){
         String sql="update student set sname=? where sid=?";
         jdbcTemplate.update(sql, "权", "1");
     }

     //测试数据库连接池是否连接成功
     @Test
     public void testDataSource() throws SQLException {
         DataSource  dataSource=ctx.getBean(DataSource.class);
         System.out.println(dataSource.getConnection());
     }

}

完整示例: http://download.csdn.net/detail/u011781521/9849263