这个是别人写的,你试一试
import java.sql.*;
import java.util.*;public class ConnBean {
private int inUse=0;
private Vector connections=new Vector();
private String poolname;
private String dbid;
private String drivername;
private String username;
private String passwd;
private int maxconn;
public ConnBean(String poolname,String dbid,String drivername,
String username,String passwd,int maxconn) {
this.poolname=poolname;
this.dbid=dbid;
this.drivername=drivername;
this.username=username;
this.passwd=passwd;
this.maxconn=maxconn;
}
public synchronized void releaseConn(Connection conn){
connections.addElement(conn);
inUse--;
}
public synchronized Connection getConn(){
Connection con=null;
if(connections.size()>0){
con=(Connection)connections.elementAt(0);
connections.removeElementAt(0);
try {
if (con.isClosed())
con = getConn();
}
catch (Exception ex) {
ex.printStackTrace();
}
}
else if(maxconn==0||inUse<maxconn){
con=newConn();
}
if(con!=null){
inUse++;
}
return con;
}
private Connection newConn(){
Connection con=null;
try{
Class.forName(drivername).newInstance();
con=DriverManager.getConnection(dbid,username,passwd);
}
catch(Exception e){
e.printStackTrace();
return null;
}
return con;
}
public synchronized void closeconn(){
Enumeration allConnections=connections.elements();
while(allConnections.hasMoreElements()){
Connection con=(Connection) allConnections.nextElement();
try{
con.close();
}
catch(SQLException e){
e.printStackTrace();
}
}
connections.removeAllElements();
}
}//管理连接池import java.sql.*;
import java.util.*;public class ConnManager {
private Vector poolnames=new Vector();
private Vector drivernames=new Vector();
private Vector dbids=new Vector();
private Vector usernames=new Vector();
private Vector passwds=new Vector();
private Vector maxcons=new Vector();
private Hashtable connPools=new Hashtable();
public ConnManager() {
//在这里创建不同类型数据库的连接池,只需在这里重写下面的代码,比如SQLSERVER,ORACLE, ACCESS,MYSQL
poolnames.addElement("连接池名");
drivernames.addElement("JDBC驱动");
dbids.addElement("url");
usernames.addElement("用户名");
passwds.addElement("密码");
maxcons.addElement("最大连接数");
createPools();
}
public void realeaseConn(String name,Connection con){
ConnBean pool=(ConnBean)connPools.get(name);
if(pool!=null)
pool.releaseConn(con);
}
public Connection getConn(String name){
ConnBean pool=(ConnBean)connPools.get(name);
if(pool!=null)
return pool.getConn();
return null;
}
public synchronized void closeConn(){
Enumeration allPools=connPools.elements();
while(allPools.hasMoreElements()){
ConnBean pool=(ConnBean)allPools.nextElement();
pool.closeconn();
}
}
private void createPools(){
for(int i=0;i<poolnames.size();i++){
String poolname=poolnames.elementAt(i).toString();
String drivername=drivernames.elementAt(i).toString();
String dbid=dbids.elementAt(i).toString();
String username=usernames.elementAt(i).toString();
String passwd=passwds.elementAt(i).toString();
int maxconn=0;
try{
maxconn=Integer.parseInt(maxcons.elementAt(i).toString());
}
catch(NumberFormatException e){
e.printStackTrace();
}
ConnBean pool=new ConnBean(poolname,dbid,drivername,username,passwd,maxconn);
connPools.put(poolname,pool);
}
}
}
import java.sql.*;
import java.util.*;public class ConnBean {
private int inUse=0;
private Vector connections=new Vector();
private String poolname;
private String dbid;
private String drivername;
private String username;
private String passwd;
private int maxconn;
public ConnBean(String poolname,String dbid,String drivername,
String username,String passwd,int maxconn) {
this.poolname=poolname;
this.dbid=dbid;
this.drivername=drivername;
this.username=username;
this.passwd=passwd;
this.maxconn=maxconn;
}
public synchronized void releaseConn(Connection conn){
connections.addElement(conn);
inUse--;
}
public synchronized Connection getConn(){
Connection con=null;
if(connections.size()>0){
con=(Connection)connections.elementAt(0);
connections.removeElementAt(0);
try {
if (con.isClosed())
con = getConn();
}
catch (Exception ex) {
ex.printStackTrace();
}
}
else if(maxconn==0||inUse<maxconn){
con=newConn();
}
if(con!=null){
inUse++;
}
return con;
}
private Connection newConn(){
Connection con=null;
try{
Class.forName(drivername).newInstance();
con=DriverManager.getConnection(dbid,username,passwd);
}
catch(Exception e){
e.printStackTrace();
return null;
}
return con;
}
public synchronized void closeconn(){
Enumeration allConnections=connections.elements();
while(allConnections.hasMoreElements()){
Connection con=(Connection) allConnections.nextElement();
try{
con.close();
}
catch(SQLException e){
e.printStackTrace();
}
}
connections.removeAllElements();
}
}//管理连接池import java.sql.*;
import java.util.*;public class ConnManager {
private Vector poolnames=new Vector();
private Vector drivernames=new Vector();
private Vector dbids=new Vector();
private Vector usernames=new Vector();
private Vector passwds=new Vector();
private Vector maxcons=new Vector();
private Hashtable connPools=new Hashtable();
public ConnManager() {
//在这里创建不同类型数据库的连接池,只需在这里重写下面的代码,比如SQLSERVER,ORACLE, ACCESS,MYSQL
poolnames.addElement("连接池名");
drivernames.addElement("JDBC驱动");
dbids.addElement("url");
usernames.addElement("用户名");
passwds.addElement("密码");
maxcons.addElement("最大连接数");
createPools();
}
public void realeaseConn(String name,Connection con){
ConnBean pool=(ConnBean)connPools.get(name);
if(pool!=null)
pool.releaseConn(con);
}
public Connection getConn(String name){
ConnBean pool=(ConnBean)connPools.get(name);
if(pool!=null)
return pool.getConn();
return null;
}
public synchronized void closeConn(){
Enumeration allPools=connPools.elements();
while(allPools.hasMoreElements()){
ConnBean pool=(ConnBean)allPools.nextElement();
pool.closeconn();
}
}
private void createPools(){
for(int i=0;i<poolnames.size();i++){
String poolname=poolnames.elementAt(i).toString();
String drivername=drivernames.elementAt(i).toString();
String dbid=dbids.elementAt(i).toString();
String username=usernames.elementAt(i).toString();
String passwd=passwds.elementAt(i).toString();
int maxconn=0;
try{
maxconn=Integer.parseInt(maxcons.elementAt(i).toString());
}
catch(NumberFormatException e){
e.printStackTrace();
}
ConnBean pool=new ConnBean(poolname,dbid,drivername,username,passwd,maxconn);
connPools.put(poolname,pool);
}
}
}
利用Oracle自带的连接池类的一例 献花给本文 投掷臭鸡蛋
利用Oracle自带的连接池类的一例 /**
封装了对数据库的连接,用于处理SQL语句。
@author:yancheng(sharetop studio)
@version:1.0.0
*/
package DBUtil; import java.sql.*;
import java.io.*;
import javax.sql.*;
import javax.naming.*;
import oracle.jdbc.pool.*; public class OraPooledSQL
{ private PooledConnection dbpool; /**
@param ConnectionURL 连接名 如: jdbc:odbc:myODBC
@param UserID 用户名
@param PassWord 用户密码
*/
public OraPooledSQL(String ConnectionURL,String UserID,String PassWord)
{ try{ OracleConnectionPoolDataSource ocpds = new OracleConnectionPoolDataSource(); ocpds.setURL(ConnectionURL); ocpds.setUser(UserID); ocpds.setPassword(PassWord); dbpool = ocpds.getPooledConnection(); }
catch(Exception ex)
{
System.err.println("Error in PooledSQL-construct : ");
ex.printStackTrace(System.err);
} }//end OraPooledSQL //close dbpool
protected void finalize()
{
if( dbpool != null )
{
try
{
dbpool.close();
}
catch(Exception ex)
{
}
}
} /**
用于更新、添加或删除的SQL语句
@param SQL SQL语句字串,如:insert into tablename values(id,......)
*/
public int Update(String SQL)
{
Statement stmt = null;
int rc = 0; Connection connection = null; try
{
connection = dbpool.getConnection();
stmt = connection.createStatement();
rc = stmt.executeUpdate(SQL);
} catch( Exception ex )
{
System.err.println("Error in Update - OraPooledSQL : ");
ex.printStackTrace(System.err);
} return rc; } //end Update()
/**
用于查询的SQL语句
@param SQL SQL语句字串,如:select * from tablename
*/
public ResultSet Query(String SQL)
{
Statement stmt = null;
ResultSet rs = null;
Connection connection = null; try
{
connection = dbpool.getConnection();
stmt = connection.createStatement();
rs = stmt.executeQuery(SQL);
} catch( Exception ex )
{
System.err.println("Error in Query - SQLBean : ");
ex.printStackTrace(System.err);
} return rs; } //end Query } //end Class
加入时间:2002-07-12; 阅读次数:815
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