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: uT1xvXfqP
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CountBean.java 3X|7 R
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/* f[r?J/;P9
* CountData.java F/8="dM
* +ftOJFkI
* Created on 2007年1月1日, 下午4:44 Hg[g{A_G[
* -!_\4
* To change this template, choose Tools | Options and locate the template under 1=o|[7
* the Source Creation and Management node. Right-click the template and choose `wGP31Y.
* Open. You can then make changes to the template in the Source Editor. ''.P=
*/ Q#gzk%jL@
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package com.tot.count; <d*;d3gm
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/** 8nV#\J9
* v$n J$M&k
* @author pk>p|q
*/ I7=g8/JD
public class CountBean { u
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private String countType; J]h$4"
int countId; {Tr5M o
/** Creates a new instance of CountData */ ko7*9`
public CountBean() {} [l`_2{:
public void setCountType(String countTypes){ ,?k0~fuG6
this.countType=countTypes; t 0 omJP
} y"bSn5B[
public void setCountId(int countIds){ 8VWkUsOoI
this.countId=countIds; "K Or)QD/
}
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public String getCountType(){ ` @PHV
return countType; 4k7
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} fS@V`"O6
public int getCountId(){ /Ko{S_3<I
return countId; JyiP3whW
} @Yzdq\FI
} An.Qi =Cv
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CountCache.java cu|S|]g
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/*
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* CountCache.java $4Vp l
* 4hQ.RO
* Created on 2007年1月1日, 下午5:01 JkfVsmc<{h
* j:Y1
* To change this template, choose Tools | Options and locate the template under dGc<{sQzB
* the Source Creation and Management node. Right-click the template and choose nuvRjd^N
* Open. You can then make changes to the template in the Source Editor. j Z6]G{
*/ MJyz0.9 c
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package com.tot.count; ]QqT.z%B
import java.util.*; __mnz``/Y
/** dRhsnT+KX
* j]6c_r3
* @author -O~V4004
*/ :6T8\W
public class CountCache { AcoU.tpP
public static LinkedList list=new LinkedList(); iHYvH
/** Creates a new instance of CountCache */ |Q|vCWel{
public CountCache() {} h=x{
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public static void add(CountBean cb){ TXH9BlDn
if(cb!=null){
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list.add(cb); 5eL_iNqJM
} G+k~k/D 6
} 1s "/R
} :nLhg$wMs
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CountControl.java 1woBw>g
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/* Fv!KLw@
* CountThread.java /c4@QbB
* o6b\
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* Created on 2007年1月1日, 下午4:57 XX9u%BZ~
* o$XJSz|6
* To change this template, choose Tools | Options and locate the template under f7du1k3
* the Source Creation and Management node. Right-click the template and choose H)5V \
* Open. You can then make changes to the template in the Source Editor. MJ%gF=$X
*/ {>]7xTpwZ
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package com.tot.count; ;ND)h pD+
import tot.db.DBUtils; 8lJMD %Df:
import java.sql.*; )=9EShz!
/** O_~vl m<#
* C)H1<Br7
* @author +\D?H.P
*/ "Vw;y+F}
public class CountControl{ BIK^<_?+ZU
private static long lastExecuteTime=0;//上次更新时间 ;zpSyyp@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 13f@Ox$
/** Creates a new instance of CountThread */ iC`mj
public CountControl() {} J;R1OJs S
public synchronized void executeUpdate(){ jb'AOs
Connection conn=null; RIg
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PreparedStatement ps=null;
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try{ $Y3mO~
conn = DBUtils.getConnection(); #ouE,<
conn.setAutoCommit(false); Pkq?tm$#
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ,x]xtg?
for(int i=0;i<CountCache.list.size();i++){ nyRQ/.3
CountBean cb=(CountBean)CountCache.list.getFirst(); 2c u?2_,
CountCache.list.removeFirst(); H}f}Y8J{
ps.setInt(1, cb.getCountId()); kCVO!@yZz
ps.executeUpdate();⑴ N5%Cwl6i
//ps.addBatch();⑵ I<}<!.Bc!
} ?E2$
//int [] counts = ps.executeBatch();⑶ F?jFFwim
conn.commit(); h+"UK=
}catch(Exception e){ c&]nAn(
e.printStackTrace(); &}."sGK
} finally{ EZw<)Q
try{ [(d))(M$|
if(ps!=null) { !J/fJW>m6
ps.clearParameters(); i^I
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ps.close(); (imaL,M-D
ps=null; c:OFBVZ
} cZFG~n/
}catch(SQLException e){} 6 $*\%
DBUtils.closeConnection(conn); =VFPZ
} O&vE 5%x
} gd=gc<z YP
public long getLast(){ a}#8n^2
return lastExecuteTime; V!XT=Ou?6
} fa:V8xa
public void run(){ qHtonJc
long now = System.currentTimeMillis(); ))xyaYIZkk
if ((now - lastExecuteTime) > executeSep) { OdWZYWj
//System.out.print("lastExecuteTime:"+lastExecuteTime); ']'V?@H]4
//System.out.print(" now:"+now+"\n"); $T-Pl57
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9cMQ51k)E
lastExecuteTime=now; 4IUdlb
executeUpdate(); Zk .V
} +Dwq>3AH
else{ 8gK
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); B*c@w~E
} w1 5QqhlK
} w /l\p3n
} R{R'byre
//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 >dU.ic?19
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类写好了,下面是在JSP中如下调用。 ?mME^?x
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<% R8(Bt73
CountBean cb=new CountBean(); +"8-)'
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Dmq_jt
CountCache.add(cb); "$6 .L^9W
out.print(CountCache.list.size()+"<br>"); A-GU:B
CountControl c=new CountControl(); L?:fyNA3[
c.run(); `rQDX<?
out.print(CountCache.list.size()+"<br>"); )o[Jxu'
%>