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: X4CiVV
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CountBean.java ac%x\e$
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/* k@P?,r
* CountData.java LZ}m;
* * -X`^R
* Created on 2007年1月1日, 下午4:44 ;pt.)5
* hV}C.- 6h
* To change this template, choose Tools | Options and locate the template under C8KV<k
* the Source Creation and Management node. Right-click the template and choose h@CP
* Open. You can then make changes to the template in the Source Editor. ^;'FC vd
*/ Xmw%f[Xl
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package com.tot.count; aNUMF
h{ T{3
/** Vl/fkd,Z
* ^Eif~v
* @author te;VGpv.
*/ :_[pZ;-@
public class CountBean { B|ctauJ
private String countType; UetI4`
int countId; )nlFyWXh.
/** Creates a new instance of CountData */ {[~dI ~
public CountBean() {} #O N^6f2
public void setCountType(String countTypes){ VQ;'SY:`
this.countType=countTypes; "EBCf.3-
} Q9k;PJ`@
public void setCountId(int countIds){ KM9H<;A
this.countId=countIds; nQ@<[KNd
} 4}-G<7*
public String getCountType(){ m:Fdgu9
return countType; x}~Z[ bx
} :Z.P0=
public int getCountId(){ zNM*xPgS
return countId; 2"EaF^?\
} zmFS]IOv$
} !@>q^_Gez
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CountCache.java 2oo\ SmO]
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/* C:.>*;?7
* CountCache.java 4mvnFY}
* #<d'=R[AK
* Created on 2007年1月1日, 下午5:01 ]JQ}9"p=5
* v >cPr(
* To change this template, choose Tools | Options and locate the template under L),r\#Y(v
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. \$!D^%~;
*/ rP IAu[],g
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package com.tot.count; xy-Vw"I[bh
import java.util.*; Q%W>m0%
/** ]F3fO5Z
* VNwOD-b/]
* @author P6A##z
*/ qwq5yt?
public class CountCache { Fg0!2MKq*
public static LinkedList list=new LinkedList(); SN]Na<P
/** Creates a new instance of CountCache */ LtGjHB\+
public CountCache() {} O-!Q~;3][
public static void add(CountBean cb){ W9;9\k
if(cb!=null){ S@Aw1i p
list.add(cb); Z|xgZG{
} kAs=5_?I
} ]IH1_?HgP7
} <vt}+uMzXv
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CountControl.java j!"5,~
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/* q4g)/x%nc
* CountThread.java F{Oaxn
* W4(GI]`_+
* Created on 2007年1月1日, 下午4:57 6Zx5^f(qd
* ~-UO^$M-
* To change this template, choose Tools | Options and locate the template under h:i FLS f
* the Source Creation and Management node. Right-click the template and choose /4;Sxx-
* Open. You can then make changes to the template in the Source Editor. ji<(}d~L*
*/ :mhO/Bx
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package com.tot.count; sF3@7~m4
import tot.db.DBUtils; e.W <pI,
import java.sql.*; ,[<$X{9
/** -/:K.SY,
* QZJnb%]
* @author KE-0/m4yJ
*/ )hC3'B/[Y
public class CountControl{ e/x6{~ju^N
private static long lastExecuteTime=0;//上次更新时间 T.W^L'L`
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 lUdk^7:M
/** Creates a new instance of CountThread */ tT+W>oA/M
public CountControl() {} ^%0^DN
public synchronized void executeUpdate(){ VO~%O.>
Connection conn=null; *y', eB
PreparedStatement ps=null; }*S`1IWMj
try{ S~)_=4Z
conn = DBUtils.getConnection(); .)<l69ZD Z
conn.setAutoCommit(false); $4Dr +Z
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Z29LtKr
for(int i=0;i<CountCache.list.size();i++){ ! F<::fN
CountBean cb=(CountBean)CountCache.list.getFirst(); 7g:Lj,Z4L
CountCache.list.removeFirst(); ez~u A4
ps.setInt(1, cb.getCountId()); IaKJ W?
ps.executeUpdate();⑴ s1t kiX{>
//ps.addBatch();⑵ 1jE {]/Y7&
} !x!1H5"
//int [] counts = ps.executeBatch();⑶ bXA%|7*
conn.commit(); K"ly\$F
}catch(Exception e){ @>&b&uj7T
e.printStackTrace(); /qFY$vj
} finally{ = ?BhtW
try{ E{}J-_oS45
if(ps!=null) { ^Jw=5ImG
ps.clearParameters(); r;p@T8k
ps.close(); o#WECs>
ps=null; M(I%QD
} )G-u;1rd
}catch(SQLException e){} y6Ez.$M
DBUtils.closeConnection(conn); LW#U+bv]Dq
} +S'm<}"1
} 8_pyfb
public long getLast(){ '}:(y$9.`
return lastExecuteTime; ].sD#~L_
} C-g,uARX(r
public void run(){ /1_O5'5+v
long now = System.currentTimeMillis(); wPq9`9 #
if ((now - lastExecuteTime) > executeSep) { .hUlI3z9
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,3!TyQ\m'
//System.out.print(" now:"+now+"\n"); 3!%-O:!
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ""Oir!4
lastExecuteTime=now; ,5j3(Lk
executeUpdate(); Q
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} f$vU$>+[
else{ rjj_]1?K
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ;-_ZWk]
} 1/i1o nu}
} gYbcBb%z
} }^VikT]>1
//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 /%gMzF
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类写好了,下面是在JSP中如下调用。 ?9>wG7cps7
mg" _3].j
<% p'6XF{
CountBean cb=new CountBean(); Zrj#4E1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); %m
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CountCache.add(cb); bdfs'udt9
out.print(CountCache.list.size()+"<br>"); 0g HV(L?
CountControl c=new CountControl(); lr?SL\D
c.run(); 2R,8q0qR:
out.print(CountCache.list.size()+"<br>"); X|D-[|P
%>