Spring的jdbcTemplate 与原始jdbc 整合c3p0的DBUtils 及Hibernate 对比

Posted 2020-11-08 Advancing Swift

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;
    }

}