JDBC??

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JDBC???

JDBC?SUN??????????????Java????????API???????????????????????????????SQL???

JDBC???

??????????????JDBC???????????????

?????????????????????JDBC???????????

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??JDBCUtils???????????????????????????????????

public class JDBCUtil {    public static Connection getConncetion() throws Exception {        InputStream is = ClassLoader.getSystemClassLoader().getResourceAsStream("jdbc.properties");        Properties pros = new Properties();        pros.load(is);        String user = pros.getProperty("user");        String password = pros.getProperty("password");        String url = pros.getProperty("url");        String driver = pros.getProperty("driver");        Class.forName(driver);        Connection conn = DriverManager.getConnection(url, user, password);        return conn;    }}

JDBCUtils???

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public class JDBCUtil {    public static void closeResource(Connection conn, PreparedStatement ps) {        try {            if (conn != null) {                conn.close();            }        } catch (SQLException e) {            e.printStackTrace();        }        try {            if (ps != null) {                ps.close();            }        } catch (SQLException e) {            e.printStackTrace();        }    }    public static void closeResource(Connection conn, PreparedStatement ps, ResultSet resultSet) {        try {            if (conn != null) {                conn.close();            }        } catch (SQLException e) {            e.printStackTrace();        }        try {            if (ps != null) {                ps.close();            }        } catch (SQLException e) {            e.printStackTrace();        }        try {            if (resultSet != null) {                resultSet.close();            }        } catch (SQLException e) {            e.printStackTrace();        }    }}

Statement??

CRUD??

Statement????????????????????SQL?????

PreparedStatement??Statement

PreparedStatement???SQL????????SQL??????????

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???????????????????????????????????????????

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????conn.setAutoCommit(false)?????????DML??????????????

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?????????C3P0?DBCP?Druid????????????

DBUtils???

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??DBUtils???QueryRunner??CRUD???????????

@Testpublic void testInsert() {    Connection conn = null;    try {        QueryRunner runner = new QueryRunner();        conn = JDBCUtil.getConnection();        String sql = "insert into customers(name,email,birth)values('??', 'achang@qq.com', '1999-03-09')";        int insertCount = runner.update(conn, sql);        System.out.println("??? " + insertCount + " ???");    } catch (Exception e) {        e.printStackTrace();    } finally {        JDBCUtil.closeResource(conn, null);    }}