Proxool是一種Java數據庫連接池技術。sourceforge下的一個開源項目,這個項目提供一個健壯、易用的連接池,最為關鍵的是這個連接池提供監控的功能,方便易用,便于發現連接泄漏的情況。
目前是和DBCP以及C3P0一起,最為常見的三種JDBC連接池技術。
日前,Hibernate官方宣布由于Bug太多不再支持DBCP,而推薦使用 Proxool或C3P0。
下面通過一個Demo說明一下如何使用:
項目結構如下:
DBLink.Java文件中的代碼:
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package com.bjpowernode.util; 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 DBLink { private Connection connection; private PreparedStatement preparedStatement; private ResultSet resultSet; static { try { Class.forName( "org.logicalcobwebs.proxool.ProxoolDriver" ); //加載驅動 } catch (ClassNotFoundException e) { System.out.println( "加載驅動失??!" ); e.printStackTrace(); } } private Connection getConn(){ try { if (connection== null ||connection.isClosed()){ connection = DriverManager.getConnection( "proxool.mysqlsource" ); //獲取連接 } } catch (SQLException e) { System.out.println( "獲取連接失??!" ); e.printStackTrace(); } return connection; } public List<Map<String, Object>> select(String sql, Object [] params){ List<Map<String, Object>> list = new ArrayList<Map<String, Object>>(); try { connection = this .getConn(); preparedStatement = connection.prepareStatement(sql); if (params != null ){ for ( int i = 0 ; i<params.length; i++){ preparedStatement.setObject(i+ 1 , params[i]); //逐一給問號賦值 } } resultSet = preparedStatement.executeQuery(); ResultSetMetaData rsmd = resultSet.getMetaData(); int columnCount = rsmd.getColumnCount(); while (resultSet.next()){ Map<String, Object> map = new HashMap<String, Object>(); for ( int i = 1 ; i<=columnCount;i++){ String columnName = rsmd.getColumnName(i); Object obj = null ; if (rsmd.getColumnTypeName(i).equals( "DATE" )){ obj = resultSet.getString(columnName); } else { obj = resultSet.getObject(columnName); } map.put(columnName, obj); } list.add(map); } } catch (SQLException e){ e.printStackTrace(); } finally { close(); } return list; } private void close(){ try { if (resultSet != null ){ resultSet.close(); } } catch (SQLException e) { e.printStackTrace(); } try { if (preparedStatement != null ){ preparedStatement.close(); } } catch (SQLException e) { e.printStackTrace(); } try { connection.close(); } catch (SQLException e) { e.printStackTrace(); } } } |
proxool.xml文件中的代碼:
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<?xml version= "1.0" encoding= "UTF-8" ?> <proxool-config> <proxool> <alias>mysqlsource</alias> <driver-url>jdbc:mysql: //localhost:3306/test</driver-url> <driver- class >com.mysql.jdbc.Driver</driver- class > <driver-properties> <property name= "user" value= "root" /> <property name= "password" value= "root" /> </driver-properties> <!-- 保留線程處于睡眠狀態的最長時間 --> <house-keeping-sleep-time> 60000 </house-keeping-sleep-time> <maximum-connection-count> 30 </maximum-connection-count> <minimum-connection-count> 10 </minimum-connection-count> <!-- 連接池中可用的連接數量(空閑狀態) --> <prototype-count> 5 </prototype-count> <maximum- new -connections> 1 </maximum- new -connections> <simultaneous-build-throttle> 1 </simultaneous-build-throttle> <!-- 連接池使用狀態 --> <statistics>30s,10m,1d</statistics> <!-- 連接池日志類型 --> <statistics-log-level>ERROR</statistics-log-level> <!-- 如果為 true ,那么每個被執行的SQL語句將會在執行期被log記錄(DEBUG LEVEL) --> <trace> true </trace> <house-keeping-test-sql>select CURRENT_DATE</house-keeping-test-sql> </proxool> </proxool-config> |
web.xml文件中的代碼:
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<?xml version= "1.0" encoding= "UTF-8" ?> <web-app version= "3.0" xmlns= "http://java.sun.com/xml/ns/javaee" xmlns:xsi= "http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http: //java.sun.com/xml/ns/javaee/web-app_3_0.xsd"> <!-- 連接池 --> <servlet> <servlet-name>ServletConfigurator</servlet-name> <servlet- class >org.logicalcobwebs.proxool.configuration.ServletConfigurator</servlet- class > <init-param> <param-name>xmlFile</param-name> <param-value>WEB-INF/proxool.xml</param-value> </init-param> <load-on-startup> 1 </load-on-startup> </servlet> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> </web-app> |
index.jsp文件中的代碼:
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<%@ page language= "java" contentType= "text/html; charset=UTF-8" pageEncoding= "UTF-8" %> <% @page import = "com.bjpowernode.util.DBLink,java.util.List,java.util.Map" %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" > <html> <head> <title>首頁</title> </head> <body> <table width= "100%" border= "1px" > <tr> <th>序號 </th><th>班級名稱</th><th>開班日期</th><th>結束日期</th><th>狀態</th><th>操作</th> </tr> <% String sql = "SELECT id, class_name, begin_date, end_date, state FROM class " ; DBLink db = new DBLink(); List<Map<String, Object>> list = db.select(sql, null ); int index = 0 ; for (Map<String, Object> map : list) { index = index + 1 ; int id = Integer.parseInt(map.get( "id" ).toString()); String className = map.get( "class_name" ).toString(); String beginDate = map.get( "begin_date" ).toString(); String endDate = map.get( "end_date" ).toString(); int state = Integer.parseInt(map.get( "state" ).toString()); String stateName = (state == 0 ? "未啟用" : "啟用" ); %> <tr align= "center" > <td><%=index%></td><td><%=className%></td><td><%=beginDate%></td><td><%=endDate%></td><td><%=stateName%></td><td>【<a href= "###" rel= "external nofollow" rel= "external nofollow" rel= "external nofollow" onclick= "" >修改</a>】【<a href= "###" rel= "external nofollow" rel= "external nofollow" rel= "external nofollow" onclick= "" >查看</a>】【<a href= "###" rel= "external nofollow" rel= "external nofollow" rel= "external nofollow" onclick= "" >刪除</a>】</td> </tr> <% } %> </table> </body> </html> |
總結
以上所述是小編給大家介紹的Java數據庫連接池之proxool,希望對大家有所幫助,如果大家有任何疑問請給我留言,小編會及時回復大家的。在此也非常感謝大家對服務器之家網站的支持!