/**
* '$RCSfile$'
* Purpose: A class represent a connection object, it includes connction
* itself, index, status, age and usageCount.
* Copyright: 2000 Regents of the University of California and the
* National Center for Ecological Analysis and Synthesis
* Authors: Jing Tao
*
* '$Author$'
* '$Date$'
* '$Revision$'
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package edu.ucsb.nceas.metacat.database;
import java.io.*;
import java.sql.*;
import org.apache.log4j.Logger;
import edu.ucsb.nceas.metacat.properties.PropertyService;
import edu.ucsb.nceas.utilities.PropertyNotFoundException;
/**
* A class represent a connection object, it includes connection itself,
* index, status, age, createtime, connection time, usageCount, warning message
*/
public class DBConnection
{
private Connection conn;
private String tag;//to idenify this object
private int status;// free or using
private long age;
private long createTime;
private long connectionTime; //how long it use for connections,
//it is accumulated
private long checkOutTime; //the time when check it out
private int usageCount;// how many time the connection was used
private int checkOutSerialNumber; // a number to identify same check out.
//for a connection
private SQLWarning warningMessage;
private String checkOutMethodName;
private static String DBDriver;
private static String DBConnectedJDBC;
private static String userName;
private static String passWord;
private static Logger logMetacat = Logger.getLogger(DBConnection.class);
/**
* Default constructor of the DBConnection class
*
*/
public DBConnection() throws SQLException
{
try {
DBDriver = PropertyService.getProperty("database.driver");
DBConnectedJDBC = PropertyService.getProperty("database.connectionURI");
userName = PropertyService.getProperty("database.user");
passWord = PropertyService.getProperty("database.password");
} catch (PropertyNotFoundException pnfe) {
System.err.println("Could not get property in static block: "
+ pnfe.getMessage());
}
conn = openConnection();
if(conn == null)
{
System.out.println("connection is null.");
}
tag = conn.toString();
status = 0;
age = 0;
createTime = System.currentTimeMillis();
connectionTime = 0;
checkOutTime = 0;
usageCount= 0;
checkOutSerialNumber=0;
warningMessage = null;
checkOutMethodName = null;
}
/**
* get the connetion from the object
*/
public Connection getConnections()
{
return conn;
}
/**
* Set a connection to this object
* @param myDBConnection, the connection which will be assign to this object
*/
public void setConnections( Connection myConnection)
{
this.conn = myConnection;
}
/**
* get the db connetion tag from the object
*/
public String getTag()
{
return tag;
}
/**
* Set a connection status to this object
* @param myTag, the tag which will be assign to this object
*/
public void setTag(String myTag)
{
this.tag = myTag;
}
/**
* get the db connetion status from the object
*/
public int getStatus()
{
return status;
}
/**
* Set a connection status to this object
* @param myStatus, the status which will be assign to this object
* 0 is free, 1 is using
*/
public void setStatus(int myStatus)
{
this.status = myStatus;
}
/**
* get the db connetion age from the object
*/
public long getAge()
{
return (System.currentTimeMillis() - createTime);
}
/**
* Set a connection age to this object
* @param myAge, the Age which will be assign to this object
*/
public void setAge(long myAge)
{
this.age = myAge;
}
/**
* get the db connetion created time from the object
*/
public long getCreateTime()
{
return createTime;
}
/**
* Set a usage number to this object
* @param myCreateTime, the create time which will be assign to this object
*/
public void setCreateTime(long myCreateTime)
{
this.createTime = myCreateTime;
}
/**
* get the how long db connetion used for the object
*/
public long getConnectionTime()
{
return connectionTime;
}
/**
* Set a connection time to this object
* It is accumulated
* @param myConnectionTime, the connection time which will assign to
* this object
*/
public void setConnectionTime(long myConnectionTime)
{
this.connectionTime = this.connectionTime + myConnectionTime;
}
/**
* get the when a db connetion was checked out
*/
public long getCheckOutTime()
{
return checkOutTime;
}
/**
* Set check out time to this object
* @param myCheckOutTime, the check out time which will assign to
* this object
*/
public void setCheckOutTime(long myCheckOutTime)
{
this.checkOutTime = myCheckOutTime;
}
/**
* get the db connetion usage times from the object
*/
public int getUsageCount()
{
return usageCount;
}
/**
* Set a usage number to this object
* @param myUsageCount, number of usage which will be assign to this object
*/
public void setUsageCount(int myUsageCount)
{
this.usageCount = myUsageCount;
}
/**
* Increase a usage number to this object
* @param myUsageCount, number of usage which will be add to this object
*/
public void increaseUsageCount(int myUsageCount)
{
this.usageCount = this.usageCount + myUsageCount;
}
/**
* get the check out serial number
*/
public int getCheckOutSerialNumber()
{
return checkOutSerialNumber;
}
/**
* Set check out serial number to this object
* @param myCheckOutSerialNumber, the check out serial number which will
* assign to this object
*/
public void setCheckOutSerialNumber(int myCheckOutSerialNumber)
{
this.checkOutSerialNumber = myCheckOutSerialNumber;
}
/**
* Increase a usage number to this object
* @param myUsageCount, number of usage which will be add to this object
*/
public void increaseCheckOutSerialNumber(int myCheckOutSerialNumber)
{
this.checkOutSerialNumber=this.checkOutSerialNumber+myCheckOutSerialNumber;
}
/**
* get the db connetion waring message from the object
*/
public SQLWarning getWarningMessage() throws SQLException
{
//should increase 1 UsageCount
increaseUsageCount(1);
return conn.getWarnings();
}
/**
* Set a warning message to this object
* @param myWarningMessage, the waring which will be assign to this object
*/
public void setWarningMessage(SQLWarning myWarningMessage)
{
this.warningMessage = myWarningMessage;
}
/**
* get the the name of method checked out the connection from the object
*/
public String getCheckOutMethodName()
{
return checkOutMethodName;
}
/**
* Set a method name to the checkOutMethodName
* @param myCheckOutMethodName, the name of method will assinged to it
*/
public void setCheckOutMethodName(String myCheckOutMethodName)
{
this.checkOutMethodName = myCheckOutMethodName;
}
/**
* Close a DBConnection object
*/
public void close() throws SQLException
{
conn.close();
tag = null;
status = 0;
age = 0;
createTime = System.currentTimeMillis();
connectionTime = 0;
checkOutTime = 0;
usageCount= 0;
warningMessage = null;
}
/**
* Method to establish DBConnection
*/
public static Connection openConnection()
throws SQLException
{
return openConnection(DBDriver, DBConnectedJDBC, userName, passWord);
}//openDBConnection
/**
* Method to establish a JDBC database connection
*
* @param dbDriver the string representing the database driver
* @param connection the string representing the database connectin parameters
* @param user name of the user to use for database connection
* @param password password for the user to use for database connection
*/
private static Connection openConnection(String dbDriver, String connection,
String user, String password)
throws SQLException
{
// Load the Oracle JDBC driver
try
{
Class.forName (dbDriver);
}
catch (ClassNotFoundException e)
{
logMetacat.error("DBConnectionPool.openConnection - Class not found: " + e.getMessage());
return null;
}
// Connect to the database
Connection connLocal = null;
connLocal = DriverManager.getConnection( connection, user, password);
return connLocal;
}//OpenDBConnection
/**
* Method to test a JDBC database connection
*
* @param dbDriver the string representing the database driver
* @param connection the string representing the database connectin parameters
* @param user name of the user to use for database connection
* @param password password for the user to use for database connection
*/
public static void testConnection(String dbDriver, String connection,
String user, String password)
throws SQLException
{
// Load the Oracle JDBC driver
try
{
Class.forName (dbDriver);
}
catch (ClassNotFoundException e)
{
throw new SQLException(e.getMessage());
}
// Connect to the database
Connection connLocal = null;
connLocal = DriverManager.getConnection( connection, user, password);
connLocal.close();
}
/**
* Method to create a PreparedStatement by sending a sql statement
* @Param sql, the sql statement which will be sent to db
*/
public PreparedStatement prepareStatement( String sql ) throws SQLException
{
return conn.prepareStatement(sql);
}//prepareStatement
/**
* Method to create a Statement
* @deprecated PreparedStatements are preferred so as to encourage
* parameter value binding
*/
public Statement createStatement() throws SQLException
{
return conn.createStatement();
}//prepareStatement
/**
* Method to make a commit command
*/
public void commit() throws SQLException
{
conn.commit();
}//commit
/**
* Method to set commit mode
* @param autocommit, true of false to auto commit
*/
public void setAutoCommit( boolean autoCommit) throws SQLException
{
conn.setAutoCommit(autoCommit);
}//setAutoCommit
/**
* Method to roll back
*/
public void rollback() throws SQLException
{
conn.rollback();
}//rollback
/**
* Method to get meta data
*/
public DatabaseMetaData getMetaData() throws SQLException
{
return conn.getMetaData();
}//getMetaData
}//DBConnection class