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: @<--5HbX
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CountBean.java 8WU
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/* ;C%40;Q
* CountData.java 59";{"sw
* 4KE"r F
* Created on 2007年1月1日, 下午4:44 SU"-%}~O#,
* CG IcuHp
* To change this template, choose Tools | Options and locate the template under $]4^ENkI
* the Source Creation and Management node. Right-click the template and choose ll{jE
* Open. You can then make changes to the template in the Source Editor. e# K =SV!H
*/ H,qIHQW#
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package com.tot.count; #d%'BUde
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/** i TY4X:x
* q{ov62t`
* @author 693J?Yah[
*/ ~#iRh6^98
public class CountBean { g^(wZ$NH
private String countType; JwbC3t):@
int countId; /Dj6Bj
}
/** Creates a new instance of CountData */ (7x5
public CountBean() {} 6%NX|4_
public void setCountType(String countTypes){ >`p`^:
this.countType=countTypes; )JE;#m0q
} aksyr$d0V<
public void setCountId(int countIds){ C$\|eC j
this.countId=countIds; <OF7:f
} o:_}=1nh
public String getCountType(){ s
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return countType; km'3[}8o&
} A!s\; C
public int getCountId(){ sM({u/
return countId; >e*m8gm#
} A1@tp/L=o
} fi+u!Y*3Z
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CountCache.java "K`B'/08^
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/*
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* CountCache.java |$#u~<r_
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* Ol:&cX3G
* Created on 2007年1月1日, 下午5:01 KDgJ~T
* F{ J>=TC
* To change this template, choose Tools | Options and locate the template under Ae:(_UJz
* the Source Creation and Management node. Right-click the template and choose oC>e'_6_b
* Open. You can then make changes to the template in the Source Editor. -_.)~)P
*/ vmL%%7
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package com.tot.count; Jt"0|+g|
import java.util.*; !>-cMI6E
/** 0Psp/H%
* mq$'\c
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* @author -0PT(gx
*/ ~YOwg\w^
public class CountCache { ;!&A
public static LinkedList list=new LinkedList(); 5Fm.] /
/** Creates a new instance of CountCache */ jNB|98NN
public CountCache() {} n[lf==R
public static void add(CountBean cb){ Qn(e[
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if(cb!=null){ C_=! ( @`8
list.add(cb); vL@N21u
} ?1i>b->
} \%=\_"^?
} ln)_Jf1r
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CountControl.java r]Bwp i%
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/* ej>8$^y
* CountThread.java
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* \v{tK;
* Created on 2007年1月1日, 下午4:57 KOGbC`TN<
* ibex:W^
* To change this template, choose Tools | Options and locate the template under d*Dq=.F(
* the Source Creation and Management node. Right-click the template and choose *:bNK5I.t
* Open. You can then make changes to the template in the Source Editor. y$7Fq'
*/ /8@JWK^I{
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package com.tot.count; a \B<(R.
import tot.db.DBUtils; e~=fo#*2?@
import java.sql.*; id@!kSR
/** &Eg>[gAIlp
* n|IdEgD$
* @author ~"!F&
*/ 9+U%k(9
public class CountControl{ 1.!rq,+>1
private static long lastExecuteTime=0;//上次更新时间 AZz
}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7$WO@yOsh
/** Creates a new instance of CountThread */ !=--pb
public CountControl() {} GM|gm-t<@
public synchronized void executeUpdate(){ +r *f2\S
Connection conn=null; 5:E7nqsNhq
PreparedStatement ps=null; kM|akG
try{ AJ` b-$Q
conn = DBUtils.getConnection(); HS.3PE0^C
conn.setAutoCommit(false); LF* 7;a
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Kf2*|ZHj
for(int i=0;i<CountCache.list.size();i++){ Um]>B`."wK
CountBean cb=(CountBean)CountCache.list.getFirst(); ~ z*
CountCache.list.removeFirst(); >3s9vdUp4h
ps.setInt(1, cb.getCountId()); cW;to Q!P
ps.executeUpdate();⑴ /=>z|?z3
//ps.addBatch();⑵ :M9'wg
} n^'ip{
//int [] counts = ps.executeBatch();⑶ .5|AX6p+^
conn.commit(); q PuxYU
}catch(Exception e){ ]=of=T:
e.printStackTrace(); ==`K$rM
} finally{ oQI3Yz
try{ sguE{!BO
if(ps!=null) { +b1(sk=4z
ps.clearParameters(); xcwyn\93)
ps.close(); K/79Tb-
ps=null; (h7 rW3
} HiCNs;t
}catch(SQLException e){} 9"1 0:\U
DBUtils.closeConnection(conn); )(TaVHJR
} ~ ?m';
} Y v }G"-=
public long getLast(){ Brr{iBz*"
return lastExecuteTime; &F9BaJ
} u*Z>&]W_
public void run(){ 7'Y 3T[
long now = System.currentTimeMillis(); R8P7JY[h
if ((now - lastExecuteTime) > executeSep) { &G7JGar
//System.out.print("lastExecuteTime:"+lastExecuteTime); ?Z
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//System.out.print(" now:"+now+"\n"); B-ReBtN
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); )+RTA
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lastExecuteTime=now; 1O*5>dkX;%
executeUpdate(); YpoO:
} EWNh:<F?
else{ ]]`hnzJX
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &Z/aM?
} !}|n3wQ
} )a.Y$![
} 4\4onCzuT
//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 =:n>yZ3T
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类写好了,下面是在JSP中如下调用。 _O2},9L n
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<% UhYeyT
CountBean cb=new CountBean(); x$d3fsEE
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )n}Wb+2I
CountCache.add(cb); A\iDK10Q$
out.print(CountCache.list.size()+"<br>"); kLQPa[u4
CountControl c=new CountControl(); :TJv<NZi'
c.run(); <8yzBp4gZ
out.print(CountCache.list.size()+"<br>"); uQazUFw
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