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: .I]v
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CountBean.java
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/* Wd(|w8J{a
* CountData.java \fSruhD
* vN@04a\h
* Created on 2007年1月1日, 下午4:44
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* VKu_l
* To change this template, choose Tools | Options and locate the template under <0hVDk~
* the Source Creation and Management node. Right-click the template and choose K4E2W9h
* Open. You can then make changes to the template in the Source Editor. #lSGH 5Fp?
*/ >gq=W5vN(
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package com.tot.count; s!yD%zO
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/** W!kF(O
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* 'qo(GGC M
* @author F3$8l[O_
*/ [;
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public class CountBean { I7SFGO
private String countType; OEzSItAI/[
int countId; xO%yjG=
/** Creates a new instance of CountData */ >b#CR/^z
public CountBean() {} Wnp[8IEU
public void setCountType(String countTypes){ X|g5tnsj`
this.countType=countTypes; qC& xuu|
} hBcklI
public void setCountId(int countIds){
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this.countId=countIds; t1oTZ
} y,KZp2 j
public String getCountType(){ n>:e8KVM;
return countType; CN-4FI)1D9
} ;Z;` BGZJ
public int getCountId(){ cFJZ|Ld
return countId; C R't
} +]yVSns
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} $:-C9N29
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CountCache.java 'cIFbjJ
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/* x2l}$(7
* CountCache.java 0|0IIgy
* kf~>%tES]
* Created on 2007年1月1日, 下午5:01 9!2$?xqym
* jE5=e</
* To change this template, choose Tools | Options and locate the template under nSZp,?^
* the Source Creation and Management node. Right-click the template and choose Kuk@x.~0m
* Open. You can then make changes to the template in the Source Editor. 0lcwc"_DZX
*/ LS#_K-
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package com.tot.count; \Km+>G
import java.util.*; 7<2?NLE8*
/** j
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* ]^a{?2ei
* @author KO}TCa
*/ -W})<{End
public class CountCache { i
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public static LinkedList list=new LinkedList(); *>o@EUArN
/** Creates a new instance of CountCache */ u+jx3aP:
public CountCache() {} ;t@^Z_z,CR
public static void add(CountBean cb){ d)$seZB
if(cb!=null){ K
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list.add(cb); 91T[@p
} eD^(*a>(
} {@-tRm&
} (~b0-3s
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CountControl.java OQyZ'
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/* %6@m~;c0
* CountThread.java pf=CP%L
* {gDoktC@M
* Created on 2007年1月1日, 下午4:57 O7,:-5h0
* ?DNeL;6
* To change this template, choose Tools | Options and locate the template under &,]yqG 2
* the Source Creation and Management node. Right-click the template and choose Aj>
* Open. You can then make changes to the template in the Source Editor. y] $-:^
*/ ,qdZ6bv,]|
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package com.tot.count; Z$)jPDSr
import tot.db.DBUtils; B|;?#okx
import java.sql.*; |l?*' =
/** k9&pX8#
* mT1Q7ta*P
* @author U/rFH9e$
*/ AIA4c"w.EO
public class CountControl{ _9iF`Q
private static long lastExecuteTime=0;//上次更新时间 ]U 1S?p
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 +gb"}
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/** Creates a new instance of CountThread */ sNC~S%[
public CountControl() {} VOp+6ho<
public synchronized void executeUpdate(){ ve(@=MJ
Connection conn=null; -PiZvge
PreparedStatement ps=null; ZQ#AE VI,
try{ cW^u4%f't'
conn = DBUtils.getConnection(); q&wv{
conn.setAutoCommit(false); ~~WX#Od*$
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); %B Rll
for(int i=0;i<CountCache.list.size();i++){ kAoh#8=
CountBean cb=(CountBean)CountCache.list.getFirst(); *AYjMCo
CountCache.list.removeFirst(); :Ui'x8yt
ps.setInt(1, cb.getCountId()); DJR r
ps.executeUpdate();⑴ )VxC v
//ps.addBatch();⑵ 6wyhL-{:
} 42DB0+_wz
//int [] counts = ps.executeBatch();⑶ ob(~4H-
conn.commit(); U }}E
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}catch(Exception e){ NX<Q}3cC
e.printStackTrace(); #~qY%X
} finally{ 9z?B@;lMc
try{ FzFP 0
if(ps!=null) { o7:"Sl2AD
ps.clearParameters(); ~T'$gl
ps.close(); AiV1
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ps=null; X,+N/nku
} Otm7j>w
}catch(SQLException e){} "I[uD)$
DBUtils.closeConnection(conn); {_J1m&/
} !f8]gT zN
} 4({Wipd
public long getLast(){ ew8Manx
return lastExecuteTime; Hb9r.;r<EW
} 'jU ;.vZex
public void run(){ v;R+{K87
long now = System.currentTimeMillis(); 0 aiE0b9c
if ((now - lastExecuteTime) > executeSep) { T7XbbU
//System.out.print("lastExecuteTime:"+lastExecuteTime); }cI _$
//System.out.print(" now:"+now+"\n"); A4VVy~sd
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zLV k7u{e
lastExecuteTime=now; 'Z^KpW
executeUpdate(); "NO*(<C.R
} eP|hxqM&9
else{ ",Fqpu&M
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); bRc~e@
} [Z+E_Lbz
} (0bXsfe
} Jd/XEs?<q
//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 K;(t@GL?
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类写好了,下面是在JSP中如下调用。 dw< b}2
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<% [S T7CrwC
CountBean cb=new CountBean(); .?-]+-J?`
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 1BA5|
CountCache.add(cb); A ]~%<=b
out.print(CountCache.list.size()+"<br>"); %;tBWyq}_
CountControl c=new CountControl(); u=!n9W~"
c.run(); <o&\/uO~H
out.print(CountCache.list.size()+"<br>"); TInp6w+u
%>