Java JDBC Database connection encapsulation and instance code __ database

Source: Internet
Author: User
Tags getmessage create database

Java JDBC Feature code encapsulation:

Package com.common.common.util.mysql;  
Import java.sql.CallableStatement;  
Import java.sql.Connection;  
Import Java.sql.DriverManager;  
Import java.sql.PreparedStatement;  
Import Java.sql.ResultSet;  
Import Java.sql.ResultSetMetaData;  
Import java.sql.SQLException;  
Import java.util.ArrayList;  
Import Java.util.HashMap;  
Import java.util.List;  

Import Java.util.Map; public class Connectiondb {/** * Database driver class name/private static final String DRIVER = "Com.mysql.jdbc.Driv  
  
    ER "; /** * Connection string/private static final String urlstr = "Jdbc:mysql://*****?useunicode=true&characterenc  
  
    Oding=utf8 ";  
  
    /** * User name */private static final String USERNAME = "* * *";  
  
    /** * Password/private static final String UserPassword = "* * *";  
  
    /** * CREATE database Connection object/private Connection connnection = null; /** * Create PreparedStatement object/Private PreparedStatement PREparedstatement = null;  
  
    /** * Create CallableStatement object/private CallableStatement callablestatement = null;  
  
    /** * Create result set object/private ResultSet ResultSet = null;  
        static {try {//Load Database driver Class.forName (DRIVER);  
            catch (ClassNotFoundException e) {System.out.println ("Load driver error");  
        System.out.println (E.getmessage ());  
        /** * Establish database connection * @return database connection/public Connection getconnection () {  
                    try {//Get connection connnection = Drivermanager.getconnection (Urlstr, USERNAME,  
        UserPassword);  
        catch (SQLException e) {System.out.println (E.getmessage ());  
    return connnection; 
     /** * INSERT Update Delete SQL statement uniform method * @param SQL SQL statement * @param params parameter array, null if no arguments * @return Number of rows affected/public int executeupdate (String sql, object[] params) {//affected number of rows int Affectedl  
          
        ine = 0;  
            try {//Get connection connnection = This.getconnection ();  
              
            Call SQL PreparedStatement = connnection.preparestatement (sql);  
                    Parameter assignment if (params!= null) {for (int i = 0; i < params.length; i++) {  
                Preparedstatement.setobject (i + 1, params[i]);  
  
        }//Execute Affectedline = Preparedstatement.executeupdate ();  
        catch (SQLException e) {System.out.println (E.getmessage ());  
        finally {//release resource CloseAll ();  
    return affectedline; /** * SQL query puts query results directly into resultset * @param SQL SQL statement * @param params parameter array, null if no argument Return Result set */private ResultSet executequeryrs (String sql, object[] params) {try {//Get connection  
              
            Connnection = This.getconnection ();  
              
            Call SQL PreparedStatement = connnection.preparestatement (sql);  
                    Parameter assignment if (params!= null) {for (int i = 0; i < params.length; i++) {  
                Preparedstatement.setobject (i + 1, params[i]);  
  
        }//Execute ResultSet = Preparedstatement.executequery ();  
        catch (SQLException e) {System.out.println (E.getmessage ());  
    return resultSet;                        /** * Gets the result set and places the result in the list * * @param SQL * SQL statement * @return List * Result set */public list<object> excutequery (String sql, object[] params) {/ /Execute SQL Get result set ResultSet rs = executequeryrs (sql, params);  
          
        Create ResultSetMetaData object ResultSetMetaData RSMD = null;  
        Result set column number int columnCount = 0;  
              
            try {rsmd = Rs.getmetadata ();  
        Get the result set column number ColumnCount = Rsmd.getcolumncount ();  
        catch (SQLException E1) {System.out.println (E1.getmessage ());  
  
        //Create list list<object> list = new arraylist<object> ();  try {//Saves the resultset result to the list while (Rs.next ()) {map<string, object>  
                Map = new hashmap<string, object> ();  
                for (int i = 1; I <= columnCount i++) {map.put (Rsmd.getcolumnlabel (i), rs.getobject (i));  
            } list.add (map); } catch (SQLException e) {System.out.printlN (e.getmessage ());  
        Finally {//Close all resources closeall ();  
    } return list;  /** * Stored procedure method with one output parameter * @param SQL stored Procedure statement * @param params parameter array * @param outparampos  Output parameter position * @param sqltype output Parameter type * @return The value of the output parameter/public Object excutequery (String sql, object[]  
        Params,int outparampos, int sqltype) {object = null;  
        Connnection = This.getconnection ();  
              
            try {//call stored procedure callablestatement = connnection.preparecall (sql);  
                    Assign a value to a parameter if (params!= null) {for (int i = 0; i < params.length; i++) {  
                Callablestatement.setobject (i + 1, params[i]);  }//Register output parameter Callablestatement.registeroutparameter (Outparampos,  
              
            SqlType);  
       Perform     Callablestatement.execute ();  
              
        Get output Parameter object = Callablestatement.getobject (Outparampos);  
        catch (SQLException e) {System.out.println (E.getmessage ());  
        finally {//release resource CloseAll ();  
    return object; /** * Close all resources */private void CloseAll () {//Close result set object if (ResultSet!= nul  
            L) {try {resultset.close ();  
            catch (SQLException e) {System.out.println (E.getmessage ());  
                }///Close PreparedStatement object if (PreparedStatement!= null) {try {  
            Preparedstatement.close ();  
            catch (SQLException e) {System.out.println (E.getmessage ()); }///Close CallableStatement Object if(CallableStatement!= null)  
            {try {callablestatement.close ();  
            catch (SQLException e) {System.out.println (E.getmessage ()); }///Close Connection object if (connnection!= null) {try {C  
            Onnnection.close ();  
            catch (SQLException e) {System.out.println (E.getmessage ());
 }  
        }     
    }  

}

MySQL Instance code calls:

Package com.common.common.util.mysql;
Import java.util.ArrayList;
Import Java.util.Date;
Import Java.util.HashMap;
Import java.util.List;

Import Java.util.Map;
Import Com.smart.entity.HomeDevice;
Import Com.smart.entity.HomeDeviceAlarm;
Import Com.smart.entity.HomeDeviceAttrStatu;
Import Com.smart.entity.HomeDeviceCommand;

Import Com.smart.entity.HomeDeviceLog; public class Connectiondbutil {public list
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