有时要为每一篇文章统计其点击次数,如果每一次浏览都要更新一次库的话,那性能在访问量很大的情况下,服务器的压力就会很大了,比较好一点的方法就是先将要更新的数据缓存起来,然后每隔一段时间再利用数据库的批量处理,批量更新库。源码如下: H6TD@kL9Wr
dP2irC%f8
CountBean.java 5II(mSg8
N5zlT
/* d(`AXyw
* CountData.java '])2k@o@
* O\KQl0*l\\
* Created on 2007年1月1日, 下午4:44 F/c$v
* sJx+8
-
* To change this template, choose Tools | Options and locate the template under &[mZD,
* the Source Creation and Management node. Right-click the template and choose )v4b
* Open. You can then make changes to the template in the Source Editor. m^~ S
*/ vxQ8t!-u
~p0c3*
package com.tot.count; q%>'4_
t(!r8!c
u}
/** _6@hTen`
* Q _iO(qu
6
* @author %^.%OCX:
*/ I751 t
public class CountBean { !5@_j,lW(
private String countType; tvKAIwe
int countId; ![6EUMx
/** Creates a new instance of CountData */ ;TiUpg</_3
public CountBean() {} :G w~7v_
public void setCountType(String countTypes){ EpJ4`{4
this.countType=countTypes; Z#l%r0(o
} T\s)le
public void setCountId(int countIds){ [P4$Khu$
this.countId=countIds; BI?@1q}:
} zhI#f0c
public String getCountType(){ S8Fmy1#
return countType; /c2'dJ(H
} ~ I}9;XT
public int getCountId(){ ?|{XZQ~
return countId; 3oZ=k]\
} '|>9C^E9X
} N/QiI.V6
C#;jYBtT7?
CountCache.java m(iR|Zx
Lw7=+h)
/* )2q~u%9n
* CountCache.java qB]i6*
* ^E`(*J/o
* Created on 2007年1月1日, 下午5:01 fQK"h
* /2M.~3gQ
* To change this template, choose Tools | Options and locate the template under nR>r2wMk@
* the Source Creation and Management node. Right-click the template and choose RF!a//
* Open. You can then make changes to the template in the Source Editor. iZ3W"Vd`b
*/ VQI(Vp|
E`H$YS3o
package com.tot.count; {Hmo1|_S|
import java.util.*; yqXH:757~
/** YNrp}KQ
* %%ae^*[!n
* @author zjL.Bhiud
*/
>YtdA
public class CountCache { ~9\WFF/
public static LinkedList list=new LinkedList(); /%aiEhL
/** Creates a new instance of CountCache */ }{ 9&:!uA
public CountCache() {} tcr//
public static void add(CountBean cb){ 5Ky#GuC
if(cb!=null){ 2O"P2(1}v
list.add(cb); gk BdR +
} :HxA`@Ok
} ,vqr<H9e
} d1@%W;qX!
e
pCLM_yA
CountControl.java YKbCdLQ
)Rat0$6
/* 8n BL\{'B[
* CountThread.java R2L;bGI*J
* 2jsw"aHW
* Created on 2007年1月1日, 下午4:57 CBQhIvq.d
* d%I"/8-J
* To change this template, choose Tools | Options and locate the template under [OTJV pC
* the Source Creation and Management node. Right-click the template and choose [ao
U5;7
* Open. You can then make changes to the template in the Source Editor. R`";Z$~{
*/ ; R=.iOn
+(D$9{y
package com.tot.count; "1q>At
import tot.db.DBUtils; :f5s4N
import java.sql.*;
+QM@VQ
/** Mr--4D0Hk
* rKHY?{!
* @author Fhz*&JC#
*/ H+}"q$
public class CountControl{ *tOG*hwdT
private static long lastExecuteTime=0;//上次更新时间 uJR%0 E7!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g>d;|sK
/** Creates a new instance of CountThread */ Ed0I WPx
public CountControl() {} Ee1LO#^_6
public synchronized void executeUpdate(){ cWGDee(
Connection conn=null; xCzebG["
PreparedStatement ps=null; Bx"7%[
try{ fW`&'!
conn = DBUtils.getConnection(); 1Kvx1p
conn.setAutoCommit(false); i`/+,<
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); b5m=7;u*h
for(int i=0;i<CountCache.list.size();i++){ MC0TaP
CountBean cb=(CountBean)CountCache.list.getFirst(); A`}yBSb
CountCache.list.removeFirst(); m|=Ecu
ps.setInt(1, cb.getCountId()); S0g'r
!;6
ps.executeUpdate();⑴ @ DZD
//ps.addBatch();⑵ O9'x-A%
} +5.t. d
//int [] counts = ps.executeBatch();⑶ ri C[lB
conn.commit(); q1y/x@
}catch(Exception e){ @`-[;?>
e.printStackTrace();
%dErnc$
} finally{ k+V6,V)my
try{ FVv8--
if(ps!=null) { v{i7h|e
ps.clearParameters(); 5!C_X5M
ps.close(); Tj~IaU
ps=null; s%iOUL2/
} k{tMzx]F__
}catch(SQLException e){} #QvMVy
DBUtils.closeConnection(conn); KtS)'jf
} 'tN25$=V&W
} L.xZ_ 6
public long getLast(){ E6Rz@"^XV
return lastExecuteTime; + SZYg[
} oIGrA-T}
public void run(){ %or,{mmiM:
long now = System.currentTimeMillis(); !KKT[28v
if ((now - lastExecuteTime) > executeSep) { A392=:N+Q
//System.out.print("lastExecuteTime:"+lastExecuteTime); UV}73Sp
//System.out.print(" now:"+now+"\n"); D7]#Xk2
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); VZ>On$hp
lastExecuteTime=now; O 2{)WWOT
executeUpdate(); ""O"
} kE.x+2
else{ K.C>
a:J
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0.r4f'vk
} #8{F9w<Rf
} !>x|7
} 7;.xc{
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ka\OJ7u
s57N) 0kP
类写好了,下面是在JSP中如下调用。 sGY_{CZ:
k>}g\a,
<% w.Ezg j
CountBean cb=new CountBean(); NRnRMY-
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0U66y6
CountCache.add(cb); |5I'CNi\
out.print(CountCache.list.size()+"<br>"); e73^#O&Xt
CountControl c=new CountControl(); d{et8N
c.run(); ogM%N
out.print(CountCache.list.size()+"<br>"); e]ig!G]
%>