Proxool是一种Java数据库连接池技术。sourceforge下的一个开源项目,这个项目提供一个健壮、易用的连接池,最为关键的是这个连接池提供监控的功能,方便易用,便于发现连接泄漏的情况。
目前是和DBCP以及C3P0一起,最为常见的三种JDBC连接池技术。
日前,Hibernate官方宣布由于Bug太多不再支持DBCP,而推荐使用 Proxool或C3P0。
下面通过一个Demo说明一下如何使用:
项目结构如下:
DBLink.Java文件中的代码:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
|
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" ); //加载驱动
} catch (ClassNotFoundException e) {
System.out.println( "加载驱动失败!" );
e.printStackTrace();
}
}
private Connection getConn(){
try {
if (connection== null ||connection.isClosed()){
connection = DriverManager.getConnection( "proxool.mysqlsource" ); //获取连接
}
} catch (SQLException e) {
System.out.println( "获取连接失败!" );
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]); //逐一给问号赋值
}
}
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文件中的代码:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
|
<?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>
<!-- 保留线程处于睡眠状态的最长时间 -->
<house-keeping-sleep-time> 60000 </house-keeping-sleep-time>
<maximum-connection-count> 30 </maximum-connection-count>
<minimum-connection-count> 10 </minimum-connection-count>
<!-- 连接池中可用的连接数量(空闲状态) -->
<prototype-count> 5 </prototype-count>
<maximum- new -connections> 1 </maximum- new -connections>
<simultaneous-build-throttle> 1 </simultaneous-build-throttle>
<!-- 连接池使用状态 -->
<statistics>30s,10m,1d</statistics>
<!-- 连接池日志类型 -->
<statistics-log-level>ERROR</statistics-log-level>
<!-- 如果为 true ,那么每个被执行的SQL语句将会在执行期被log记录(DEBUG LEVEL) -->
<trace> true </trace>
<house-keeping-test-sql>select CURRENT_DATE</house-keeping-test-sql>
</proxool>
</proxool-config>
|
web.xml文件中的代码:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
|
<?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">
<!-- 连接池 -->
<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文件中的代码:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
|
<%@ 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>首页</title>
</head>
<body>
<table width= "100%" border= "1px" >
<tr>
<th>序号 </th><th>班级名称</th><th>开班日期</th><th>结束日期</th><th>状态</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 ? "未启用" : "启用" );
%>
<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= "" >删除</a>】</td>
</tr>
<%
}
%>
</table>
</body>
</html>
|
总结
以上所述是小编给大家介绍的Java数据库连接池之proxool,希望对大家有所帮助,如果大家有任何疑问请给我留言,小编会及时回复大家的。在此也非常感谢大家对服务器之家网站的支持!