原文地址https://blog.csdn.net/jq_ak47/article/details/55049639

 

Mysql for java 的JDBC 驱动库安装

1、将下载下来的5.1.40的.zip文件解压缩到合适目录； 

2、将mysql-connector-java-5.1.40-bin.jar文件路径添加到CLASSPATH路径中

D:\Dev\JDBC\mysql-connector-java-5.1.40\mysql-connector-java-5.1.40-bin.jar

 

关于是否需要将这个文件路径添加到CLASSPATH中去，添不添加感觉不是很大事， 

实践:

package db;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; public class DbDemo { public static void main(String[] args) { // TODO Auto-generated method stub ResultSet result = null; Connection con = null; Statement statement = null; try { // 第0步：将mysql 的jdbcjar包加入到引用库中来 // 第一步：将想要连接的数据库驱动类加载到JVM中来，加载过程中并向DriverManager注册Driver // 成功加载后，会将Mysql的驱动Driver类的实例注册到DriverManager类中。 //使得下面我们获取Connection只需要通过DriverManager就可以了。我不需要通过每个数据库具体的Driver。 Class.forName("com.mysql.jdbc.Driver").newInstance(); // 第二步,通过DriverManager获取一个和mysql的连接实例con String JDBCUrl = "jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8";// String userName = "root"; String password = "1557862201"; // 接受一个jdbcurl，username，password； con = DriverManager.getConnection(JDBCUrl, userName, password); // 第三步：通过con连接获取到Statement实例，执行sql语句 statement = con.createStatement();// statement实例是用于一些不带参数的sql执行，查询，更新，插入，删除操作都可以但是需要构建一个没有占位符的sql字符串 // 第四步，statement执行sql语句，查询到的结果集到ResultSet实例，简单查询，没有where语句的查询 result = statement.executeQuery("select * from student"); // 第五步：从结果集中获取数据 while (result.next()) { // 根据test库中student表格列名读取数据 int id = result.getInt("id"); String name = result.getString("_stuName"); String number = result.getString("_stuNumber"); String Grade = result.getString(result.findColumn("_stuGrade")); String Address = result.getString(result.findColumn("_stuAddress")); System.out .println("name= " + name + " number= " + number + " Grade= " + Grade + " Address= " + Address); } // 插入语句 // statement.executeUpdate(""); insert(statement); // 执行带参数的查询，有where语句的查询 int id = 2; executeQuery(con, id); // 执行更新操作 updateDate(con, 2); delete(con, "XX");// 删除数据行 } catch (ClassNotFoundException e) { // TODO Auto-generated catch block System.out.println("找不到驱动程序类 ，加载驱动失败！"); e.printStackTrace(); } catch (InstantiationException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IllegalAccessException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (SQLException ex) { // TODO Auto-generated catch block System.out.println("SQLException: " + ex.getMessage()); System.out.println("SQLState: " + ex.getSQLState()); System.out.println("VendorError: " + ex.getErrorCode()); ex.printStackTrace(); } finally { // 第六步：释放资源 /** * 关闭JDBC对象 操作完成以后要把所有使用的JDBC对象全都关闭，以释放JDBC资源，关闭顺序和声 明顺序相反： 1、关闭记录集 * 2、关闭声明 3、关闭连接对象 */ if (result != null) { // 关闭结果集 try { result.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } result = null; } if (statement != null) { // 关闭执行sql语句代码块 try { statement.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } statement = null; } if (con != null) { // 关闭连接 try { con.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } con = null; } } } /** * 删除一行数据记录 * * @param con * @param name * @throws SQLException */ private static void delete(Connection con, String name) throws SQLException { // TODO Auto-generated method stub System.out.println("delete begin"); Statement statement = con.createStatement(); String delete = "delete from student where _stuName= " + "'" + name + "'"; System.out.println(delete); statement.executeUpdate(delete); if (statement != null) statement.close(); statement = null; System.out.println("delete end"); } /** * sql更新数据记录 * * @param con * @param id * @throws SQLException */ private static void updateDate(Connection con, int id) throws SQLException { // TODO Auto-generated method stub System.out.println("update begin"); PreparedStatement statement = null; ResultSet result = null; String name = "'mm'"; String update = "update student set _stuName= " + name + "where id= ?"; statement = con.prepareStatement(update); statement.setInt(1, id); statement.executeUpdate(); if (result != null) result.close(); result = null; if (statement != null) statement.close(); statement = null; System.out.println("update end"); } /** * 带参数的查询 * * @param con * @param id * @throws SQLException */ private static void executeQuery(Connection con, int id) throws SQLException { System.out.println("begin"); // TODO Auto-generated method stub PreparedStatement statement = null; ResultSet result; String query = "select * from student where id = ? and _stuName = ?"; statement = con.prepareStatement(query); statement.setInt(1, id);// 第一个占位符的参数 statement.setString(2, "Cindy");// 第二个占位符的参数 result = statement.executeQuery(); while (result.next()) { id = result.getInt("id"); String name = result.getString("_stuName"); String number = result.getString("_stuNumber"); String Grade = result.getString(result.findColumn("_stuGrade")); String Address = result.getString(result.findColumn("_stuAddress")); System.out.println("有参数的查询"); System.out.println("name= " + name + " number= " + number + " Grade= " + Grade + " Address= " + Address); System.out.println("带参数查询成功"); } if (result != null) result.close(); result = null; if (statement != null) statement.close(); statement = null; System.out.println("end"); } /** * 进行插入数据行 * * @param statement * @throws SQLException */ private static void insert(Statement statement) throws SQLException { // TODO Auto-generated method stub String update = "insert low_priority into student(_stuName, _stuNumber, _stuGrade, _stuAddress)" + "values('XX',2100120,'大三','兴国县')";// 降低insert的执行优先级，同理update，delete操作也是一样的 statement.executeUpdate(update); System.out.println("insert successfully"); } }