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: QS^~77q
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CountBean.java ndr)3tuYu
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/* 88
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* CountData.java fO6[!M(
* xPt*CB
* Created on 2007年1月1日, 下午4:44 7skljw(
* ZT6V/MD7T.
* To change this template, choose Tools | Options and locate the template under 0x\2#i
* the Source Creation and Management node. Right-click the template and choose 7!pLK&_
* Open. You can then make changes to the template in the Source Editor. (qUK7$
*/ cQX:%Ix=
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package com.tot.count; {&-#s#&
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/** f27)v(EJ
* k=?^){[We
* @author Jn=42Q:>
*/ \]I
public class CountBean { 8"x9#kyU<3
private String countType; #:#Dz.$L
int countId; Tp?-*K
/** Creates a new instance of CountData */ kae2 73"
public CountBean() {} ?mMW*ico
public void setCountType(String countTypes){ :s"2Da3B
this.countType=countTypes; wZjlHe
} fp{G|.SA
public void setCountId(int countIds){ 8.yCA
this.countId=countIds; c_#*mA"+
} Rv<L#!;
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public String getCountType(){ ^2EhlK^)
return countType; }%$OU = T
} ?KB@Zm+#~
public int getCountId(){ Ad/($v5+
return countId; xI?0N<'.*q
} eRs&iK2y
} ox[ .)v
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CountCache.java 3V}(fnv
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/* o&z!6"S<
* CountCache.java 3C M^j<9
* Q.A \U>AgV
* Created on 2007年1月1日, 下午5:01 0 _A23.Y
* hU"F;4p
* To change this template, choose Tools | Options and locate the template under o\4CoeG
* the Source Creation and Management node. Right-click the template and choose BxdX WO
* Open. You can then make changes to the template in the Source Editor. ?ok)>P
*/ eLV.qLBUs
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package com.tot.count; /;l[I=VI
import java.util.*; fagM7)x
/** #Ao !>qCE
* 1[-vD=
* @author `*aBRwvK~
*/ Lc]1$
public class CountCache { 2JZdw
public static LinkedList list=new LinkedList(); fQU{SjG
/** Creates a new instance of CountCache */ tuxRVV8l
public CountCache() {} NEVp8)w
public static void add(CountBean cb){ s?c JV`
if(cb!=null){ 5/?P|T
list.add(cb); @7W?8
} qSTW b%
} rslvsS:
} Jf_%<\ O
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CountControl.java @?Zf-.
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/* j (ygQ4T
* CountThread.java b7Oj<!Wo`
* "|t!7hC
* Created on 2007年1月1日, 下午4:57 H)>sTST(
* 68e[:wf
* To change this template, choose Tools | Options and locate the template under [T^?Q%h
* the Source Creation and Management node. Right-click the template and choose dJD(\a>r.u
* Open. You can then make changes to the template in the Source Editor. OlY$v@|
*/ CU$#0f>
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package com.tot.count; LZ<[ll#C
import tot.db.DBUtils; m`}{V5;
import java.sql.*; IQnIaZ
/** z9DcnAs
* x2W#ROfg
* @author $1Z6\G O
*/ ;:]\KJm}?
public class CountControl{ ?S tsH
private static long lastExecuteTime=0;//上次更新时间 H}ZQ?uK;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |V|+lx'sc
/** Creates a new instance of CountThread */ %3o`j<
public CountControl() {} =&vFVIhWcf
public synchronized void executeUpdate(){ q
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Connection conn=null; !SxG(*u
PreparedStatement ps=null; & mt)d
try{ vt1lR5
conn = DBUtils.getConnection(); !{Z~<Ky
conn.setAutoCommit(false); E[g*O5
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (9C<K<
for(int i=0;i<CountCache.list.size();i++){ &<]<a_pw
CountBean cb=(CountBean)CountCache.list.getFirst(); :iPym}CE
CountCache.list.removeFirst(); )9L/sKz
ps.setInt(1, cb.getCountId()); 2k5/SV
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ps.executeUpdate();⑴ $yu?.b
9H#
//ps.addBatch();⑵ ub K7B |p
} rv7{Ow_Y
//int [] counts = ps.executeBatch();⑶ z|N3G E(.@
conn.commit(); rHz||jjU
}catch(Exception e){ M 2q"dz
e.printStackTrace(); %,UPJn
} finally{ Vf $Dnu@}z
try{ {whvTN1#dh
if(ps!=null) { ,}SCa'PB
ps.clearParameters(); eQDX:b
ps.close(); 3EK9,:<Cf
ps=null; k'3Wt*i
} 6.c^u5;
}catch(SQLException e){} Z?G&.# :
DBUtils.closeConnection(conn); 0-d>I@j
} /4irAG% Oj
} 5@!st
public long getLast(){ -e]7n*}H$
return lastExecuteTime; z#6?8y2-
} ,d_Gn!
public void run(){ .iwZ*b{
long now = System.currentTimeMillis(); pA}S5x
if ((now - lastExecuteTime) > executeSep) { YY5!_k
//System.out.print("lastExecuteTime:"+lastExecuteTime); R 94^4I
//System.out.print(" now:"+now+"\n"); I)SG wt-
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Jn&7C
lastExecuteTime=now; @)6jE!LC
executeUpdate(); pv,45z0
} 5h{`<W
else{ +-$Ko fnM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); h6D^G5i
} BS1Ap
} B.dT)@Lx0
} ('[TLHP
//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 kHK0(bYK
</`yd2 >
类写好了,下面是在JSP中如下调用。 7'lZg<z{~j
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<% m#7*:i&@Y
CountBean cb=new CountBean(); }6u2*(TmD
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8|^CK|m6*
CountCache.add(cb); {*m ?Kc7k
out.print(CountCache.list.size()+"<br>"); SPkn3D6
CountControl c=new CountControl(); ipE]}0q
c.run(); {KL5GowH
out.print(CountCache.list.size()+"<br>"); Z u*K-ep"
%>