Spring的jdbcTemplate 与原始jdbc 整合c3p0的DBUtils 及Hibernate 对比 Spring配置文件生成约束的菜单方法

时间:2023-03-10 01:09:50
Spring的jdbcTemplate 与原始jdbc 整合c3p0的DBUtils 及Hibernate 对比 Spring配置文件生成约束的菜单方法

以User为操作对象

package com.swift.jdbc;

public class User {

    private Long user_id;
private String user_code;
private String user_name;
private String user_password;
private String user_state; public User() {
super();
// TODO Auto-generated constructor stub
}
public User(Long user_id, String user_code, String user_name, String user_password, String user_state) {
super();
this.user_id = user_id;
this.user_code = user_code;
this.user_name = user_name;
this.user_password = user_password;
this.user_state = user_state;
}
public Long getUser_id() {
return user_id;
}
public void setUser_id(Long user_id) {
this.user_id = user_id;
}
public String getUser_code() {
return user_code;
}
public void setUser_code(String user_code) {
this.user_code = user_code;
}
public String getUser_name() {
return user_name;
}
public void setUser_name(String user_name) {
this.user_name = user_name;
}
public String getUser_password() {
return user_password;
}
public void setUser_password(String user_password) {
this.user_password = user_password;
}
public String getUser_state() {
return user_state;
}
public void setUser_state(String user_state) {
this.user_state = user_state;
}
@Override
public String toString() {
return "User [user_id=" + user_id + ", user_code=" + user_code + ", user_name=" + user_name + ", user_password="
+ user_password + ", user_state=" + user_state + "]";
} }

原始JDBC

这个注意ResultSet 是一个带指针的结果集,指针开始指向第一个元素的前一个(首元素),不同于iterator 有hasNext() 和next() ,他只有next()

package com.swift.jdbc;

import java.beans.PropertyVetoException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List; import com.mchange.v2.c3p0.ComboPooledDataSource; public class DemoJDBC { public static void main(String[] args) throws ClassNotFoundException, SQLException, PropertyVetoException { findAll();
User user=findById(9l);
System.out.println(user);
user.setUser_name("HanMeimei");
update(user);
} private static void update(User user) throws PropertyVetoException, SQLException { ComboPooledDataSource dataSource=new ComboPooledDataSource();
dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/crm");
dataSource.setDriverClass("com.mysql.jdbc.Driver");
dataSource.setPassword("root");
dataSource.setUser("root");
dataSource.setMinPoolSize(5);
dataSource.setMaxIdleTime(2000);
Connection con= dataSource.getConnection();
String sql="update sys_user set user_name='"+user.getUser_name()+"' where user_id="+user.getUser_id();
PreparedStatement statement = con.prepareStatement(sql);
statement.executeUpdate();
System.out.println("ok"); } private static User findById(long id) throws ClassNotFoundException, SQLException { Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/crm","root","root");
Statement statement = con.createStatement();
ResultSet rs = statement.executeQuery("select * from sys_user where user_id="+id);
User user=null;
while(rs.next()) {
user=new User(rs.getLong("user_id"),rs.getString("user_code"),
rs.getString("user_name"),rs.getString("user_password"),
rs.getString("user_state"));
}
return user; } private static void findAll() throws ClassNotFoundException, SQLException { Class.forName("com.mysql.jdbc.Driver");
Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/crm?user=root&password=root");
PreparedStatement statement = connection.prepareStatement("select * from sys_user");
ResultSet rs = statement.executeQuery();
List<User> list=new ArrayList<>();
while(rs.next()) {
Long id = rs.getLong("user_id");
String code=rs.getString("user_code");
String name=rs.getString("user_name");
String password=rs.getString("user_password");
String state=rs.getString("user_state");
User user=new User();
user.setUser_code(code);
user.setUser_id(id);
user.setUser_password(password);
user.setUser_name(name);
user.setUser_state(state);
list.add(user);
}
for(User u:list) {
System.out.println(u);
}
rs.close();
connection.close();
} }

整合c3p0的DBUtils

c3p0整合了连接数据库的Connection ,提供更快速的连接

package com.swift.c3p0;

import java.sql.Connection;
import java.sql.SQLException; import javax.sql.DataSource; import com.mchange.v2.c3p0.ComboPooledDataSource; public class C3P0Utils { private static ComboPooledDataSource dataSource = new ComboPooledDataSource();
private static ThreadLocal<Connection> thread=new ThreadLocal<>();
// static {
// try {
// dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/crm");
// dataSource.setDriverClass("com.mysql.jdbc.Driver");
// dataSource.setUser("root");
// dataSource.setPassword("root");
// dataSource.setMinPoolSize(5);
// } catch (PropertyVetoException e) {
// e.printStackTrace();
// }
// } public static DataSource getDataSource() {
return dataSource;
} public static Connection getConnection() {
Connection con = thread.get();
if(con==null) {
try {
con = dataSource.getConnection();
thread.set(con);
con=thread.get();
} catch (SQLException e) {
e.printStackTrace();
}
}
return con; }
public static void main(String[] args) {
Connection con = C3P0Utils.getConnection();
System.out.println(con);
}
}

并可以直接加载xml配置文件,强于(DBCP连接池,他只支持properties文件)

<c3p0-config>
<default-config>
<property name="jdbcUrl">jdbc:mysql://localhost:3306/crm</property>
<property name="driverClass">com.mysql.jdbc.Driver</property>
<property name="user">root</property>
<property name="password">root</property>
</default-config>
</c3p0-config>

DBUtils的杀手锏QueryRunner

可以使用?了,放置恶意注意,也提供自动增加' '符号,这个要注意

package com.swift.dbutils;

import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List; import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler; import com.swift.c3p0.C3P0Utils;
import com.swift.jdbc.User; public class DemoQueryRunner { private static QueryRunner qr=new QueryRunner(C3P0Utils.getDataSource());
static List<User> users=new ArrayList<User>(); public static void main(String[] args) throws SQLException {
//查找所有
users=findAll();
for(User user:users) { System.out.println(user);
}
//通过Id查找
User user=findById(9l);
System.out.println(user);
//更新
user.setUser_name("韩梅梅");
System.out.println("===================================");
System.out.println(user);
update(user); } private static void update(User user) throws SQLException { int update = qr.update(
"update sys_user set user_name=? where user_id=?",user.getUser_name(),user.getUser_id());
System.out.println(user.getUser_name()+update); } private static List<User> findAll() throws SQLException {
List<User> users = qr.query("select * from sys_user ", new BeanListHandler<User>(User.class));
return users;
} private static User findById(long l) throws SQLException { User user = qr.query(
"select * from sys_user where user_id=?",new BeanHandler<User>(User.class),l);
return user; } }

Hibernate 有个核心配置文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<!-- 约束在hibernate-core-5.0.7.Final.jar的org.hibernate包下的hibernate-configuration-3.0.dtd文件中找 -->
<hibernate-configuration>
<session-factory>
<!-- 配置方法:资料\hibernate-release-5.0.7.Final\project\etc\hibernate.properties -->
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/crm</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">root</property> <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property> <property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
<property name="hibernate.c3p0.max_size">10</property>
<property name="hibernate.c3p0.min_size">5</property>
<property name="hibernate.c3p0.timeout">5000</property> <property name="hibernate.hbm2ddl.auto">update</property>
<property name="hibernate.show_sql">true</property>
<property name="hibernate.format_sql">true</property> <property name="hibernate.connection.isolation">2</property> <!-- 获得当前session放在当前线程中 -->
<!-- <property name="hibernate.current_session_context_class">thread</property> --> <mapping resource="com/swift/hibernate/User.hbm.xml"/>
</session-factory>
</hibernate-configuration>
<property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
这个是使用Hibernate自带的c3p0功能,不需要自己写c3p0.xml文件,但除了需要c3p0的jar包,还需要Hibernate自带的jar包,可以在hibernate包的lib->optional->c3p0中找到,
此文件夹中这两个jar:c3p0-0.9.1.jar和hibernate-c3p0-4.2.1.Final.jar都要用,否则异常
Could not instantiate connection provider [org.hibernate.service.jdbc.connections.internal.C3P0ConnectionProvider]

还有个实体类的映射文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<!-- 约束在hibernate-core-5.0.7.Final.jar的org.hibernate包下的hibernate-mapping-3.0.dtd文件中找 -->
<hibernate-mapping>
<class name="com.swift.hibernate.User" table="sys_user">
<id name="user_id" column="user_id">
<generator class="native"></generator>
</id>
<property name="user_code" column="user_code"></property>
<property name="user_name" column="user_name"></property>
<property name="user_password" column="user_password"></property>
<property name="user_state" column="user_state"></property>
</class>
</hibernate-mapping>

连接数据库是通过session

package com.swift.hibernate;

import java.util.ArrayList;
import java.util.List; import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration; public class DemoHibernate { static List<User> users=new ArrayList<User>();
public static void main(String[] args) { users=findAll();
for(User user:users) { System.out.println(user);
}
}
private static List<User> findAll() { //new Configuration()是创建Configuration类对象,调用里面的configure方法,读取配置信息,方法返回的又是Configuration类型
Configuration config=new Configuration().configure();
SessionFactory sf = config.buildSessionFactory();
Session session = sf.openSession();
Query query = session.createQuery("from User");
users= query.list();
session.close();
return users;
} }



使用Spring的jdbcTemplate

关于倒包

Spring 总共有20个包看需要导入,其他还有spring的官方扩展包 (整合的较常用的一些,可根据功能导入)

这里只要实现数据库,所以,倒spring的4个核心包beans context core expression 2个日志log4j commons-loging(可不倒)

c3p0要倒 连接数据库mysql-connector-java  还有Spring的spring-jdbc 事务spring-tx 用注解要spring-aop

配置文件菜单法生成

applicationContext.xml(非官方约定俗成的,其实叫什么都可以)

约束如果不想拷贝,可以用菜单导入 window --> preferences -->搜索(xml catalog) -->add-->file system(注意:把location最后的约束文件名复制到key的最后)

导入后

在xml配置文件中,输入Spring的根标签<beans></beans> 然后切换到design视图右击选择 -->namespace-->勾选xsi(这时约束的约束,必须有,控制后面所有)

-->add-->specify new namespace -->location hint (把刚才添加的约束导入)-->把去约束文件名的网址复制到 namespace name -->prefix随便起个名(一般叫约束名

)

最后注意:beans不要有prefix 要设置为空,否则没有标签提示

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://www.springframework.org/schema/beans" xmlns:aop="http://www.springframework.org/schema/aop"
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-4.2.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-4.2.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.2.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-4.2.xsd "> <context:component-scan base-package="com.swift"></context:component-scan>
<context:property-placeholder location="classpath:db.properties"/> <bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="driverClass" value="${driverClass}"></property>
<property name="jdbcUrl" value="${jdbcUrl}"></property>
<property name="user" value="${user}"></property>
<property name="password" value="${password}"></property>
</bean> </beans>

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

扫描src目录下的properties文件使用${key}加载value 据说是spring的el语言spel

感觉这里直接写也可以,单独拿到properties文件里可能不会感觉乱哄哄一堆

测试结果

package com.swift.jdbctemplate;

import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List; import javax.sql.DataSource; import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate; public class DemoJdbcTemplate { private static ApplicationContext context=new ClassPathXmlApplicationContext("applicationContext.xml");
private static DataSource dataSource = (DataSource) context.getBean("dataSource");
private static JdbcTemplate jdbcTemplate=new JdbcTemplate(dataSource); public static void main(String[] args) throws SQLException { User user=new User(null,null,"甲鱼不是龟","456","0");
add(user);
List<User> users=new ArrayList<>();
users=findAll();
System.out.println(users);
user=findById(23l);
System.out.println(user);
} private static User findById(long l) {
return jdbcTemplate.queryForObject(
"select * from sys_user where user_id=?", new BeanPropertyRowMapper<User>(User.class),l);
} private static List<User> findAll() { return jdbcTemplate.query("select * from sys_user", new BeanPropertyRowMapper<User>(User.class));
} private static void add(User user) { jdbcTemplate.update("insert into sys_user values(?,?,?,?,?)",
null,null,user.getUser_name(),user.getUser_password(),user.getUser_state());
System.out.println("插入记录成功");
} }