目录：

package com.it.common; import com.it.utils.Account; import com.itheima.uitl.JDBCUtil02; import org.junit.Test; import javax.sql.rowset.JdbcRowSet; import java.sql.*; public class CommonCRUDUtil { class A implements ResultHandler{ @Override public Account handler(ResultSet resultSet) { try { while (resultSet.next()){ Account account = new Account(); String name = resultSet.getString("name"); int money = resultSet.getInt("money"); account.setMoney(money); account.setName(name); return account; } }catch (SQLException e){ e.printStackTrace(); } return null; } } //通用的查方法 @Test public void testFindall(){ Account account = findall("select * from account where id=?",new A(),6); System.out.println(account.toString()); } public T findall(String sql, ResultHandler handler, Object...args){ Connection conn = null; PreparedStatement ps = null; try { conn = JDBCUtil02.getConn(); ps = conn.prepareStatement(sql); ParameterMetaData metaData = ps.getParameterMetaData(); int count = metaData.getParameterCount(); for (int i = 0; i < count; i++) { ps.setObject(i+1, args[i]); } // 查询得到结果集 ResultSet resultSet = ps.executeQuery(); // 把得到的结果集交给调用者，让它去封装数据 T t = (T) handler.handler(resultSet); return t; } catch (SQLException e) { e.printStackTrace(); }finally { JDBCUtil02.release(conn, ps); } return null; } // 通用的增删改方法 @Test public void testUpdate(){ updata02("insert into account values(?,?,?)",8,6000,"womengl"); } public void update(String sql, Object...args){ Connection conn = null; PreparedStatement ps = null; try { conn = JDBCUtil02.getConn(); ps = conn.prepareStatement(sql); for (int i = 0; i < args.length; i++) { ps.setObject(i+1, args[i]); } ps.executeUpdate(); } catch (SQLException e) { e.printStackTrace(); }finally { JDBCUtil02.release(conn, ps); } } public void updata02(String sql, Object ... args){ Connection conn = null; PreparedStatement ps = null; try { conn = JDBCUtil02.getConn(); ps = conn.prepareStatement(sql); // 获取参数源数据对象 ParameterMetaData metaData = ps.getParameterMetaData(); // 获取参数的总数 int count = metaData.getParameterCount(); for (int i = 0; i < count; i++) { ps.setObject(i+1, args[i]); } ps.executeUpdate(); } catch (SQLException e) { e.printStackTrace(); }finally { JDBCUtil02.release(conn, ps); } } } package com.it.common; import java.sql.ResultSet; public interface ResultHandler { // 定义了一个数据封装的规则，或者是规范 T handler(ResultSet resultSet); } package com.itheima.uitl; import java.sql.Connection; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import javax.sql.DataSource; import com.mchange.v2.c3p0.ComboPooledDataSource; public class JDBCUtil02 { static ComboPooledDataSource dataSource = null; static{ dataSource = new ComboPooledDataSource(); } // public static DataSource getDataSource(){ // return dataSource; // } /** * 获取连接对象 * @return * @throws SQLException */ public static Connection getConn() throws SQLException{ return dataSource.getConnection(); } /** * 释放资源 * @param conn * @param st * @param rs */ public static void release(Connection conn , Statement st , ResultSet rs){ closeRs(rs); closeSt(st); closeConn(conn); } public static void release(Connection conn , Statement st){ closeSt(st); closeConn(conn); } private static void closeRs(ResultSet rs){ try { if(rs != null){ rs.close(); } } catch (SQLException e) { e.printStackTrace(); }finally{ rs = null; } } private static void closeSt(Statement st){ try { if(st != null){ st.close(); } } catch (SQLException e) { e.printStackTrace(); }finally{ st = null; } } private static void closeConn(Connection conn){ try { if(conn != null){ conn.close(); } } catch (SQLException e) { e.printStackTrace(); }finally{ conn = null; } } }

jdbc配置 driverClass=com.mysql.jdbc.Driver url=jdbc:mysql://localhost/wzdata name=root password=root

c3p0-config <?xml version="1.0" encoding="UTF-8"?> com.mysql.jdbc.Driverjdbc:mysql://localhost:3306/wzdataroot123456103030100

来源：博客园

作者：进击中的青年

链接：https://www.cnblogs.com/lishi-jie/p/11800439.html