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在JSP里有两种实现的办法，一种是用JNDI(Java Naming Directory Interface)，这可能和应用服务器有关，假如是Resin，先在resin.conf里定义 <resource-ref> <res-ref-name>jdbc/oracle</res-ref-name> <res-type>javax.sql.DataSource</res-type> <init-param driver-name="oracle.jdbc.driver.OracleDriver"/> <init-param url="jdbc:oracle:thin:@192.168.1.1:1521:oracle"/> <init-param user="system"/> <init-param password="manager"/> <init-param max-connections="20"/> <init-param max-idle-time="30"/> </resource-ref> 假如为Tomcat，在Server.xml里面定义，有关的资料可以查文档，然后在jsp里这样用 try{ javax.naming.Context env = (Context)new InitialContext().lookup("java:comp/env"); javax.sql.DataSource pool=(javax.sql.DataSource) env.lookup("jdbc/oracle"); }catch(Exception e){System.err.println("Exception error:"+e.getMessage());} try { Connection conn = pool.getConnection(); }catch(Exception e){System.out.println("Exception error:"+e.getMessage());} 通过这段代码，你就获得从连接池里获得了一个连接conn。假如想用普通的连接池，那只能用JavaBean了，先写一个ConnectionPool的java的类，然后直接从连接池中获得连接，下面是我一个连接池的JavaBean ConnectionPool.java如下： import java.io.PrintStream; import java.sql.Connection; import java.util.Vector; // Referenced classes of package com.ilovejsp.sql: // DataSource, PooledConnection public class ConnectionPool { private Vector pool; private int size; DataSource db; public ConnectionPool() { pool = null; size = 0; db = new DataSource(); } public void setSize(int value) { if(value > 1) size = value; } public int getSize() { return size; } public synchronized void initPool() throws Exception { try { for(int x = 0; x < size; x++) { Connection conn = db.getConnection(); if(conn != null) { PooledConnection pcon = new PooledConnection(conn); addConnection(pcon); } } } catch(Exception e) { System.err.println(e.getMessage()); } } private void addConnection(PooledConnection pcon) { if(pool == null) pool = new Vector(size); pool.addElement(pcon); } public synchronized void releaseConnection(Connection conn) { int x = 0; do { if(x >= pool.size()) break; PooledConnection pcon = (PooledConnection)pool.elementAt(x); if(pcon.getConnection() == conn) { System.err.println("Release Connection".concat(String.valueOf(String.valueOf(x)))); pcon.setInUse(false); break; } x++; } while(true); } public synchronized Connection getConnection() throws Exception { PooledConnection pcon = null; for(int x = 0; x < pool.size(); x++) { pcon = (PooledConnection)pool.elementAt(x); if(!pcon.inUse()) { pcon.setInUse(true); return pcon.getConnection(); } } try { Connection conn = db.getConnection(); pcon = new PooledConnection(conn); pcon.setInUse(true); pool.addElement(pcon); } catch(Exception e) { System.err.println("Exception error:".concat(String.valueOf(String.valueOf(e.getMessage())))); } return pcon.getConnection(); } public synchronized void emptyPool() { for(int x = 0; x < pool.size(); x++) { System.err.println("Closing Jdbc Connection".concat(String.valueOf(String.valueOf(x)))); PooledConnection pcon = (PooledConnection)pool.elementAt(x); if(!pcon.inUse()) { pcon.close(); continue; } try { Thread.sleep(3000L); pcon.close(); } catch(Exception e) { System.out.println("Exception :".concat(String.valueOf(String.valueOf(e.getMessage())))); } } db.close(); } } testpool.jsp内容如下： <%@ page language="java" contentType="text/html;charset=gb2312"%> <%@ page import="java.sql.*"%> <HTML> <HEAD> <TITLE>系统数据信息</TITLE> </HEAD> <BODY> <%ConnectionPool db=new ConnectionPool(); Connection conn=db.getConnection(); Statement stmt=conn.createStatement(); String sql1="select * from pg_database "; ResultSet rs=stmt.executeQuery(sql1); %> <TABLE><TR><TD>系统数据库信息</TD></TR> <TR><TD> <%while(rs.next()) { %> <%=rs.getString(1)%> <%} rs.close();%> </TR></TD> <TABLE><TR><TD>系统字段信息</TD></TR> <TR><TD> <%String sql2="select * from pg_type"; rs=stmt.executeQuery(sql2); while(rs.next()) { %> (<%=rs.getString(1)%>) <%} rs.close(); db.close();%> </TR></TD> </BODY> </HTML> 返回类别: 教程 上一教程: JBOSS下MS SQL SERVER配置指导 下一教程: 在JSP页面中实现检索数据的分页显示 您可以阅读与"JSP中实现连接池"相关的教程: · JSP用连接池连数据库的问题 · Java 实现连接sql server 2000（JDBC数据库访问例子） · 数据库连接池Java实现小结 · JSP中TOMCAT的SQL SERVER2000数据库连接池的配置 · 在JSP中实现分页 |
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