JDBC Link Database

It's simple, but sometimes it only leaves an impression.

 Public classJdbcutil {StaticString URL =NULL; StaticString username =NULL; StaticString Password =NULL; StaticString Driverclass =NULL; Static {        Try{Properties Properties=NewProperties (); InputStream in= Jdbcutil.class. getResourceAsStream ("/jdbc.properties");            Properties.load (in); URL= Properties.getproperty ("url"); Username= Properties.getproperty ("username"); Password= Properties.getproperty ("Password"); Driverclass= Properties.getproperty ("Driver");            SYSTEM.OUT.PRINTLN (password);        Class.forName (Driverclass); } Catch(Exception e) {e.printstacktrace (); System.out.println ("Drive failed to load!" "); Throw NewRuntimeException (e); }    }     Public StaticConnection getconnection () {Try{Connection conn=drivermanager.getconnection (URL, username, password); returnConn; } Catch(SQLException e) {e.printstacktrace (); Throw NewRuntimeException (e); }    }     Public Static voidClose (Connection Conn, Statement St, ResultSet rs) {if(Conn! =NULL) {            Try{conn.close (); } Catch(Exception e) {Throw NewRuntimeException (e); }        }        if(St! =NULL) {            Try{st.close (); } Catch(Exception e) {Throw NewRuntimeException (e); }        }        if(rs! =NULL) {            Try{rs.close (); } Catch(Exception e) {Throw NewRuntimeException (e); }        }    }     Public Static voidClose (Connection conn, Statement St) {if(Conn! =NULL) {            Try{conn.close (); } Catch(Exception e) {Throw NewRuntimeException (e); }        }        if(St! =NULL) {            Try{st.close (); } Catch(Exception e) {Throw NewRuntimeException (e); }        }    }         /** Release Resources*/     Public Static voidreleaseresources (ResultSet ResultSet, Statement Statement, Connection Connection) {Try {            if(ResultSet! =NULL) Resultset.close (); } Catch(SQLException e) {e.printstacktrace (); } finally{ResultSet=NULL; Try {                if(Statement! =NULL) Statement.close (); } Catch(SQLException e) {e.printstacktrace (); } finally{statement=NULL; Try {                    if(Connection! =NULL) Connection.close (); } Catch(SQLException e) {e.printstacktrace (); } finally{Connection=NULL; }            }        }    }}

Importjava.sql.Connection;Importjava.sql.PreparedStatement;ImportJava.sql.ResultSet;Importjava.sql.SQLException;Importjava.sql.Statement;ImportBean. Quackresults;//Add new functions to the database/*** 2017/10/21 *@authorLemo **/ Public classDbexcute {PrivateConnection Connection; PrivateStatement Statement; PrivateResultSet ResultSet; //Update Action     Public voidupdate (String sql) {Try{Connection=jdbcutil.getconnection (); Statement=connection.createstatement (); //Can create, modify, delete tables, add, delete, modify tuples, and query SQL statements            Booleannum=statement.execute (SQL);        SYSTEM.OUT.PRINTLN (num); } Catch(SQLException e) {e.printstacktrace (); } finally{Jdbcutil.close (connection, (com.mysql.jdbc.Statement) Statement, ResultSet); }    }    //Query Operations     PublicResultSet Query (String sql) {Try{Connection=jdbcutil.getconnection (); Statement=connection.createstatement (); ResultSet=statement.executequery (SQL); } Catch(SQLException e) {e.printstacktrace (); } finally{jdbcutil.releaseresources (resultSet, statement, connection); }        returnResultSet; }    //Add Action     Public voidaddelement (String sql) {update (SQL); }     Public voidaddelement (quackresults aquackresults) {/*String sqlstr = "select* from users where username=?"         and password=? ";        Connection = Jdbcutil.getconnection ();        PreparedStatement Astatement=null;            try {astatement=connection.preparestatement (SQLSTR);            Astatement.setstring (1, "Zhansgan");        Astatement.setstring (2, "root");        } catch (SQLException e) {//TODO auto-generated catch block E.printstacktrace (); }*/String sqlstr= "INSERT into mine_quack_results values (null,?,?,?,?,?)"; Connection=jdbcutil.getconnection (); PreparedStatement astatement=NULL; Try{astatement=connection.preparestatement (SQLSTR); Astatement.setdouble (1, Aquackresults.getxdata ()); Astatement.setdouble (2, Aquackresults.getydata ()); Astatement.setdouble (3, Aquackresults.getzdata ()); Astatement.settimestamp (4, Aquackresults.getquacktime ()); Astatement.setdouble (5, Aquackresults.getquackgrade ());            System.out.println (Astatement.execute ());        Connection.close (); } Catch(SQLException e) {//TODO auto-generated Catch blockE.printstacktrace (); }            }    //Delete Operation     Public voidremoveelement (String sql) {update (SQL); }    //Create a table     Public voidcreatetable (String sql) {update (SQL); }    //Delete a table     Public voiddroptable (String sql) {update (SQL); }}

driver=com.mysql.jdbc.Driverurl=jdbc:mysql://localhost:3306/ks?useunicode=true& Characterencoding=utf8&allowmultiqueries=trueusername=rootpassword=root# Defines the initial number of connections InitialSize=0#定义最大连接数maxActive=20#定义最大空闲maxIdle=20#定义最小空闲minIdle=1# Define the maximum wait time maxwait=60000

JDBC Link Database