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: ,XJ
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CountBean.java "ApVgNB
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/* :QV-!
* CountData.java =83FCq"
* gISG<!+X^
* Created on 2007年1月1日, 下午4:44 T3W?-,
* Jbrjt/OG#I
* To change this template, choose Tools | Options and locate the template under p*_^JU(<p
* the Source Creation and Management node. Right-click the template and choose ksB-fOv*N
* Open. You can then make changes to the template in the Source Editor. a2MFZe
*/ )ZcwG(o0
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package com.tot.count; TC%ENxDR
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/** {xzs{)9|Y4
* y p}a&Dg
* @author #@#/M)
*/ EqV]/0-\
public class CountBean { dP0%<Q|
private String countType; QX]~|?q
int countId; t%`GXJb
/** Creates a new instance of CountData */ t[ Zoe+&
public CountBean() {} sKvz<7pag
public void setCountType(String countTypes){ sfv{z!mo
this.countType=countTypes; <ETR6r
} d0Jaa1b~O
public void setCountId(int countIds){ bCv^za]P6
this.countId=countIds; f""+jc1
} F"k.1.
public String getCountType(){ ?Z]5
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return countType; |@a.dgz,
} aWe?n;
public int getCountId(){ ;E"TOC
return countId; [-*1M4D9
} ?'@tx4#v\2
} d1"%sI
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CountCache.java }5 2]
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/* xTy[X"sJ
* CountCache.java _.ny<r:g
* xzqgem`[\
* Created on 2007年1月1日, 下午5:01 U=<d;2N#
* X~`<ik{q
* To change this template, choose Tools | Options and locate the template under *Z+8L*k97
* the Source Creation and Management node. Right-click the template and choose b xU13ESv
* Open. You can then make changes to the template in the Source Editor. PW[NW-S`c
*/ `H_.<``>
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package com.tot.count; \
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import java.util.*; OqaVp/,
/** b*7:{FXg
* 1Rrl59}5
* @author I(cy<ey+e
*/ kFJ sB,2-
public class CountCache { errT7&@,A
public static LinkedList list=new LinkedList(); Zr&~gXmVS
/** Creates a new instance of CountCache */ jP]I>Tq
public CountCache() {} 3kl<~O|Fs
public static void add(CountBean cb){ ^X&n-ui
if(cb!=null){ rM
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list.add(cb); WxN@&g(
} rW~hFSrV[o
} zSpL^:~
} Jj~c&LxrO
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CountControl.java 'q#$^='o
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/* @dy<=bh~
* CountThread.java _* xjG \!
* tKnvNOhn
* Created on 2007年1月1日, 下午4:57 ,}("es\b
* (#dwIBBFt
* To change this template, choose Tools | Options and locate the template under F|eKt/>e
* the Source Creation and Management node. Right-click the template and choose A@-A_=a,
* Open. You can then make changes to the template in the Source Editor. ]/o0p
*/ MQ9Nn|4
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package com.tot.count; bD&^-&
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import tot.db.DBUtils; Qj?qWVapA
import java.sql.*; ^*
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/** I$#B#w?!$r
* YPjjSi:#
* @author C&&*6E5
*/ $yZ(c#L
public class CountControl{ ;W/K7}
private static long lastExecuteTime=0;//上次更新时间 \Bg;^6U
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ),G?f {`!
/** Creates a new instance of CountThread */ jkPye{j
public CountControl() {} muAI$IRR
public synchronized void executeUpdate(){ @E(_H$|E
Connection conn=null; ( 5^bU<
PreparedStatement ps=null; 6vx0F?>_
try{ +YL9gNN>P
conn = DBUtils.getConnection(); ZQZBap"
conn.setAutoCommit(false); =~OH.=9\
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); NA%(ZRSg(
for(int i=0;i<CountCache.list.size();i++){ Z*Sa%yf
CountBean cb=(CountBean)CountCache.list.getFirst(); c
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CountCache.list.removeFirst(); aR
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ps.setInt(1, cb.getCountId()); B=>:w%<Ii
ps.executeUpdate();⑴ #B;~i6h]
//ps.addBatch();⑵ (XQBBt
} k/"^W.B aj
//int [] counts = ps.executeBatch();⑶ x1gf o!BN
conn.commit(); -QUr|:SK:
}catch(Exception e){ ?r~|B/]
e.printStackTrace(); B,@<60u
} finally{ _TB,2 R
try{ ;*3OkNxa3
if(ps!=null) { l5> H\
ps.clearParameters(); ` )9nBZ
ps.close(); 4K_ fN
ps=null; tWs ]Zd
} tD G[}j
}catch(SQLException e){} 6#,VnS)`q
DBUtils.closeConnection(conn); l3d^V&Sk
} `}b#O}z)^
} 5 A/[x$q
public long getLast(){ ,rvw E
return lastExecuteTime; %gF; A*
} !>~W5c^
public void run(){ !+&Rn\e%7
long now = System.currentTimeMillis(); b(hnou S
if ((now - lastExecuteTime) > executeSep) { WUVRwJ 5
//System.out.print("lastExecuteTime:"+lastExecuteTime); [d(@lbV0
//System.out.print(" now:"+now+"\n"); ZyJdz+L{@V
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); IZ<d~ [y
lastExecuteTime=now; 9t
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executeUpdate(); UStNUNCq
} $6W o$c%
else{ o%!8t_1mR
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6ty>0
} Jj<UtD+
} oKl^Ttr
} xQ4'$rL1d
//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 3DNw=Ic0k
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类写好了,下面是在JSP中如下调用。 ^E)Kse.>
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<% q/
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CountBean cb=new CountBean(); z9@Tg=#i
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $1QQidB
CountCache.add(cb); `MMh"# xN
out.print(CountCache.list.size()+"<br>"); #=tWjInm
CountControl c=new CountControl(); NWuJ&+gcO5
c.run(); J&64tQl*
out.print(CountCache.list.size()+"<br>"); iKy_DV;J
%>