java新手笔记34 连接数据库

1.JdbcUtil

package com.yfs.javase.jdbc;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class JdbcUtil {
	private static final String driver = "sun.jdbc.odbc.JdbcOdbcDriver";
	private static final String url = "jdbc:odbc:driver={Microsoft Access Driver (*.mdb)};DBQ=school.mdb";

	// 获取连接方法
	public static Connection getConnection() {
		Connection conn = null;
		// 连接数据库
		try {
			Class.forName(driver);
			conn = DriverManager.getConnection(url);
		} catch (ClassNotFoundException e) {
			System.out.println("驱动类找不到...");
		} catch (SQLException e) {
			System.out.println("连接数据库失败...");
		}
		return conn;
	}

	// 释放连接
	public static void release(ResultSet rs, Statement st, Connection conn) {
		try {
			if (rs != null) {
				rs.close();
			}
		} catch (SQLException e) {
			e.printStackTrace();
		} finally {
			try {
				if (st != null) {
					st.close();
				}
			} catch (SQLException e) {
				e.printStackTrace();
			} finally {
				try {
					if(conn != null) {
						conn.close();
					}
				} catch (SQLException e) {
					e.printStackTrace();
				}
			}
		}
	}

}

2.连接信息：jdbc.properties文件

##oracle\u9A71\u52A8
jdbc.driver = oracle.jdbc.OracleDriver
jdbc.url = jdbc:oracle:thin:@YEMA203-13:1521:YFS_DB
jdbc.username = scott
jdbc.password = tiger

##SQL Server 2005
#jdbc.driver = com.microsoft.sqlserver.jdbc.SQLServerDriver
#jdbc.url = jdbc:sqlserver://localhost:1434;databaseName=YFS_DB
#jdbc.username = sa
#jdbc.password = 

##MySQL
#jdbc.driver = com.mysql.jdbc.Driver
#jdbc.url = jdbc:mysql://localhost:3306/test
#jdbc.username = root
#jdbc.password = root

##Access
#jdbc.driver = sun.jdbc.odbc.JdbcOdbcDriver
#jdbc.url = jdbc:odbc:driver={Microsoft Access Driver (*.mdb)};DBQ=YFS_DB.mdb    "... DBQ="+application.getRealPath("/Data/ReportDemo.mdb")
#jdbc.username =
#jdbc.password =

3.JdbcDemo1测试sql执行（增，查，改，删）

package com.yfs.javase.jdbc;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;

public class JdbcDemo1 {

	public static void main(String[] args) throws Exception {
		 //createTable();
		//insertData();
		//upData();
		//deleteData();
		create();
	}

	public static void create() throws Exception {
		Connection conn = JdbcUtil.getConnection();
		Statement st = conn.createStatement();
		// 执行的sql语句
		String sql = "create table stu(id int primary key, name char(30), score int)";
		// 执行
		st.execute(sql);
		// 关闭连接
		JdbcUtil.release(null, st, conn);
		System.out.println("表创建成功...");

	}

	public static void deleteData() throws Exception {
		Connection conn = JdbcUtil.getConnection();
		Statement st = conn.createStatement();
		// 执行的sql语句
		String sql = "delete from stu where id=102";
		// 执行
		st.execute(sql);
		// 关闭连接
		JdbcUtil.release(null, st, conn);
		System.out.println("删除数据成功...");

	}

	public static void upData() throws Exception {
		Connection conn = JdbcUtil.getConnection();
		Statement st = conn.createStatement();
		// 执行的sql语句
		String sql = "update stu set score=80 where id=102";
		// 执行
		st.execute(sql);
		// 关闭连接
		st.close();
		conn.close();
		System.out.println("更新数据成功...");

	}

	public static void insertData() throws Exception {
		// 加载驱动
		Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
		// url
		String url = "jdbc:odbc:driver={Microsoft Access Driver (*.mdb)};DBQ=E:/school.mdb";
		// 获取连接
		Connection conn = DriverManager.getConnection(url);// url 数据库地址
		// 执行对象
		Statement st = conn.createStatement();
		// 执行的sql语句
		//String sql = "insert into stu(id,name,score) values(101,'野马',98)";
		String sql = "insert into stu(id,name,score) values(102,'变形金刚4',65)";
		// 执行
		st.execute(sql);
		// 关闭连接
		st.close();
		conn.close();
		System.out.println("插入数据成功...");

	}

	public static void createTable() throws Exception {
		// 加载驱动
		Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
		// url
		String url = "jdbc:odbc:driver={Microsoft Access Driver (*.mdb)};DBQ=E:/school.mdb";
		// 获取连接
		Connection conn = DriverManager.getConnection(url);// url 数据库地址
		// 执行对象
		Statement st = conn.createStatement();
		// 执行的sql语句
		String sql = "create table stu(id int primary key, name char(30), score int)";
		// 执行
		st.execute(sql);
		// 关闭连接
		st.close();
		conn.close();
		System.out.println("数据库操作成功...");
	}

}

4.Server3

package com.yfs.javase;

import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;

public class Server3 {

	/**
	 * 启动服务 监听端口
	 */
	public static void main(String[] args) throws Exception {
		ServerSocket server = new ServerSocket(3000);
		// 启动
		System.out.println("服务器启动，监听3000端口...");
		final Socket socket = server.accept();// 监听是否有其他主机连接
		String other = socket.getInetAddress().getHostAddress();
		System.out.println(other + "请求连接...");
		// 接收信息 启动多线程
		new Thread(new Runnable() {
			@Override
			public void run() {
				InputStream in = null;
				BufferedReader read = null;
				while (true) {
					try {
						in = socket.getInputStream();
						read = new BufferedReader(new InputStreamReader(in));
						String msg = read.readLine();
						if (msg != null) {
							System.out.println("客户端说 ： " + msg);
						}
					} catch (IOException e) {
						e.printStackTrace();
					}
				}
			}
		}).start();

		// 发送信息 获取输出流
		OutputStream out = socket.getOutputStream();
		BufferedOutputStream buf = new BufferedOutputStream(out);
		PrintWriter pw = new PrintWriter(new OutputStreamWriter(buf),true);
		pw.println("这是服务器发送的信息....");
		Scanner scan = new Scanner(System.in);
		String msg = scan.next();
		while (!msg.equals("bye")) {
			pw.println(msg);
			msg = scan.next();
		}
		pw.close();
		buf.close();
		out.close();
		System.out.println("信息发送完成");

	}

}

4.Client3

package com.yfs.javase;

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.Socket;
import java.util.Scanner;

public class Client3 {

	/**
	 * @param args
	 */
	public static void main(String[] args) throws Exception {
		final Socket socket = new Socket("192.168.1.30", 3000);
		// 接收信息
		new Thread(new Runnable() {
			@Override
			public void run() {
				InputStream in = null;
				BufferedReader read = null;
				try {
					in = socket.getInputStream();
					read = new BufferedReader(new InputStreamReader(in));
					String msg = read.readLine();
					while (msg != null) {
						System.out.println("服务器说：" + msg);
						msg = read.readLine();
					}
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}).start();

		// 发送信息
		OutputStream out = socket.getOutputStream();
		PrintWriter pw = new PrintWriter(new OutputStreamWriter(out), true);
		Scanner scan = new Scanner(System.in);
		String msg = scan.next();
		while (!msg.equals("bye")) {
			pw.println(msg);
			msg = scan.next();
		}
		out.close();
		pw.close();

	}

}