package org.example.utils;
import java.sql.*;
public class JavaDateConnection {
 /**
  * 獲取數(shù)據(jù)庫(kù)連接
  * @return Connection
  */
 public Connection getConn() {
 //project為數(shù)據(jù)庫(kù)名
  String url = "jdbc:mysql://localhost:3306/project";
  //用戶名
  String username = "root";
  //密碼
  String password = "Hyk59308";
  Connection conn = null;
  try {
  //注冊(cè)驅(qū)動(dòng)
   Class.forName("com.mysql.jdbc.Driver");
   //classLoader,加載對(duì)應(yīng)驅(qū)動(dòng)
   conn = DriverManager.getConnection(url, username, password);
  } catch (ClassNotFoundException e) {
   e.printStackTrace();
  } catch (SQLException e) {
   e.printStackTrace();
  }
  return conn;
 }

String sql1="insert into myTable values(?,?,?,?)";//定義sql語(yǔ)句
		String sql2="select * from myTable";    //定義sql語(yǔ)句
		int result=0;    //修改操作的返回值是一個(gè)整數(shù)，即受影響的行數(shù)

``/**
			 * PreparedStatement繼承自Statement接口,PreparedStatement的對(duì)象已預(yù)編譯過(guò)，
			 * 執(zhí)行速度快于Statement對(duì)象,創(chuàng)建其對(duì)象時(shí)，需要SQL命令字符串作為對(duì)象
			 */
			PreparedStatement ps=connection.prepareStatement(sql1);   
			ps.setString(1,"tanker");
			ps.setString(2, "m");
			ps.setString(3,"1991-11-20");
			ps.setString(4, "Franch");
			result=ps.executeUpdate();
			if(result>0)
				System.out.println("插入成功");
			else
				System.out.println("插入失敗");
			//Statement用于將sql語(yǔ)句發(fā)送到數(shù)據(jù)庫(kù)
			Statement statement=connection.createStatement();
			//執(zhí)行數(shù)據(jù)庫(kù)操作返回的結(jié)果集,其定義的是數(shù)據(jù)庫(kù)游標(biāo)
			ResultSet results=statement.executeQuery(sql2); 
			System.out.println("name"+" "+"sex"+" "+"birth"+" "+"birthaddr");
			System.out.println("------------------------");
			while(results.next())
			{
				System.out.println(results.getString("name")+" "+
							  results.getString("sex")+" "+
							  results.getString("birth")+" "+
							  results.getString("birthaddr"));
			}
			System.out.println("搞定！");

 * 關(guān)閉Connection PreparedStatement
  * @param connection
  * @param preparedStatement
  */
 public static void closeConnection(Connection connection, PreparedStatement preparedStatement, ResultSet resultSet){
  if (resultSet != null) {
   try {
    resultSet.close();
   } catch (SQLException e) {
    e.printStackTrace();
   }
  }
  if (preparedStatement != null) {
   try {
    preparedStatement.close();
   } catch (SQLException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
  }
  if (connection != null) {
   try {
    connection.close();
   } catch (SQLException e) {
    e.printStackTrace();
   }
  }
 }

package util;
import com.alibaba.druid.pool.DruidDataSourceFactory;

import javax.sql.DataSource;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;

import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

public class DBUtil {
 private static DataSource ds;
 static {
  //1.加載配置文件
  Properties pro = new Properties();
  try {
   pro.load(DBUtil.class.getClassLoader().getResourceAsStream("/db.properties"));
   //獲取DataSource
   ds = DruidDataSourceFactory.createDataSource(pro);
  } catch (IOException e) {
   e.printStackTrace();
  } catch (Exception e) {
   e.printStackTrace();
  }
 }
 //獲取連接
 public static Connection getConnection() throws SQLException {
  return ds.getConnection();
 }

/**
  * @param sql SQL語(yǔ)句
  * @param objs	SQL語(yǔ)句占位符實(shí)參，如果沒(méi)有參數(shù)則傳入null
  * @return 返回增刪改的結(jié)果，類型為int
  */
 public static int executeDML(String sql,Object...objs){
  // 聲明jdbc變量
  Connection conn = null;
  PreparedStatement ps = null;
  int i = -1;
  try {
   // 獲取連接對(duì)象
   conn = DBUtil.getConnection();
   // 開(kāi)啟事務(wù)管理
   conn.setAutoCommit(false);
   // 創(chuàng)建SQL命令對(duì)象
   ps = conn.prepareStatement(sql);
   // 給占位符賦值
   if(objs!=null){
    for(int j=0;j<objs.length;j++){
     ps.setObject(j+1,objs[j]);
    }
   }
   // 執(zhí)行SQL
   i = ps.executeUpdate();
   conn.commit();
  } catch (Exception e) {
   try {
    conn.rollback();
   } catch (SQLException e1) {
    // TODO Auto-generated catch block
    e1.printStackTrace();
   }
   e.printStackTrace();
  } finally {
   DBUtil.closeAll(null, ps, conn);
  }
  return i;
 }

//關(guān)閉資源
 public static void closeAll(ResultSet rs,Statement stmt,Connection conn){
  try {
   if(rs!=null){
    rs.close();
   }
  } catch (SQLException e1) {
   // TODO Auto-generated catch block
   e1.printStackTrace();
  }
  try {
   stmt.close();
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
  try {
   conn.close();
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }