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: HtY\!_Ea
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CountBean.java 5[I> l
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/* QwOQS
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* CountData.java 6JRee[
* `ZV;Le'
* Created on 2007年1月1日, 下午4:44 xkUsZ*X8B
* Ofqe+C
* To change this template, choose Tools | Options and locate the template under ~<v`&Gm?"
* the Source Creation and Management node. Right-click the template and choose M%&`&{
* Open. You can then make changes to the template in the Source Editor. }kL%l
*/ K*
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package com.tot.count; 'y-IE#!5
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/** 34JkB+#a
* 5?9}^s4
* @author Vl^jTX5N
*/ 5I T'u3V
public class CountBean { [p4a\Qg0
private String countType; }qV4]*+{
int countId; .RJvu$U2j
/** Creates a new instance of CountData */ zRvYN
public CountBean() {} =*Wl;PI'
public void setCountType(String countTypes){ L$@RSKYp
this.countType=countTypes; q#sMew\{
} B+zq!+ HJ
public void setCountId(int countIds){ * +A!12s@
this.countId=countIds; &??(EA3
} = \X<UA}
public String getCountType(){ oH6(Lq'q
return countType; 2U~oWg2P
} lt,x(2
public int getCountId(){ wZfR>|f
return countId; &lI.N~Ao
} n)`*{uv$
} +/Y)s5@<
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CountCache.java h3@mN\=h'
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/* *%Gy-5hM
* CountCache.java I|WBT
* xu+wi>Y^
* Created on 2007年1月1日, 下午5:01 8(Z*Vz uu
* zac>tXU;
* To change this template, choose Tools | Options and locate the template under db#y]>^l
* the Source Creation and Management node. Right-click the template and choose BvX!n"QIb
* Open. You can then make changes to the template in the Source Editor. qY14LdC}~
*/ -pqShDar|
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package com.tot.count; OkzfQ
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import java.util.*; cE]tvL:g
/** C=PBF\RkKu
* ;2dhue
* @author 7!MW`L/`
*/ HCHC~FNd
public class CountCache { 00b
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public static LinkedList list=new LinkedList(); &,)9cV /
/** Creates a new instance of CountCache */ !(SaE'
public CountCache() {} 7z%zXDe~T[
public static void add(CountBean cb){ `]tXQqD
if(cb!=null){ AFMAgf{bD
list.add(cb); ,C=Fgxw(
} -QZped;?*
} Z71"d"
} 3j.f3~"
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CountControl.java (#Y2H
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/* 4qyL' \d[
* CountThread.java @9vz%1B<l
* ej!C^
* Created on 2007年1月1日, 下午4:57 ]^Q`CiKd
* x5PQ9Bw,
* To change this template, choose Tools | Options and locate the template under "F%cn@l
* the Source Creation and Management node. Right-click the template and choose w,`x(!&
* Open. You can then make changes to the template in the Source Editor. jr!x)yd
*/ p(Qm\g<
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package com.tot.count; +(|T\%$DT
import tot.db.DBUtils; '{OZ[$E
import java.sql.*; {mkYW-4Se
/** kTC6fNj[
* SrHRpxy
* @author ?J<4IvL/
*/ C'5i>;
public class CountControl{ UTs0=:+,t
private static long lastExecuteTime=0;//上次更新时间 3s>&h-E
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 r ."Dc
/** Creates a new instance of CountThread */ F*I{?NRN1
public CountControl() {} xQJdt$]U@
public synchronized void executeUpdate(){ 26\1tOj Np
Connection conn=null; Q*KEODR8\
PreparedStatement ps=null; VK?,8Y
try{ Uyi_B.:`
conn = DBUtils.getConnection(); C= hE@
conn.setAutoCommit(false); M:C*?;K:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); KZDB \T
for(int i=0;i<CountCache.list.size();i++){ [
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CountBean cb=(CountBean)CountCache.list.getFirst(); -4hX-
CountCache.list.removeFirst(); &1B)mj
ps.setInt(1, cb.getCountId()); ]@WJ&e/'@
ps.executeUpdate();⑴ :5"|iRP'
//ps.addBatch();⑵ 5RlJybN"o
} I{1w8m4O6
//int [] counts = ps.executeBatch();⑶ g~Q#U;]
conn.commit(); |0-5-.
}catch(Exception e){ O[`n{Vl/
e.printStackTrace(); y f+/Kj<
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} finally{ _Thc\{aV#
try{ 6o,,w^
if(ps!=null) { JLg_oK6
ps.clearParameters(); o.k#|q
ps.close(); g<{~f
ps=null; ZC0F:=/K
} 0HG*KW
}catch(SQLException e){} Q7#Q6-Q
DBUtils.closeConnection(conn); B VPf8!-
} T]E$H, p
} pGsVO5M?
public long getLast(){ t/q\Ne\\,
return lastExecuteTime; Gm.v-T$
} l}<s~ip
public void run(){ 9prG@
long now = System.currentTimeMillis(); KE(kR>OB]
if ((now - lastExecuteTime) > executeSep) { h!)(R<
//System.out.print("lastExecuteTime:"+lastExecuteTime); uYO?Rb&}
//System.out.print(" now:"+now+"\n"); y)(@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Is88+,O
lastExecuteTime=now; I98wMV8
executeUpdate(); c?z%z&
} JDMaLo
else{ Bpqq-_@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); xp,H5
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} j[Et+V?
} )ns;S
} 8K1+ttjm
//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 ZY][LU~l8
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类写好了,下面是在JSP中如下调用。 R?]>8o,
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<% 3btciR!N]
CountBean cb=new CountBean(); lz # inC|
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); [i&tE.7
CountCache.add(cb); d5u,x.R
out.print(CountCache.list.size()+"<br>"); 8(S'g+p
CountControl c=new CountControl(); D{G#|&;
c.run(); 9K%E+_7b
out.print(CountCache.list.size()+"<br>"); UB(8N7_/
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