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: 4XSq\.@G
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CountBean.java {#z[iiB
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/* QiNLE'19^
* CountData.java 4H`B]Zt7
* HC|
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* Created on 2007年1月1日, 下午4:44 \OkJX_7
* E4<#6q
* To change this template, choose Tools | Options and locate the template under g+-^6UG
* the Source Creation and Management node. Right-click the template and choose dlMjy$/T
* Open. You can then make changes to the template in the Source Editor. w^[:wzF0
*/ '_" S/X+v
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package com.tot.count; 5qkyi]/U8
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/** \\Nt^j3qR
* 0RN 7hpf&`
* @author SU(J
*/ xN6}4JB
public class CountBean { a@#<qf8g
private String countType; +#6f)H(P]
int countId; DKG;up0
/** Creates a new instance of CountData */ Zk5AZ R!|
public CountBean() {} 6dYa07
public void setCountType(String countTypes){ 2c3/iYCKP
this.countType=countTypes; WmE4TL^8?
} AA}+37@2I
public void setCountId(int countIds){ n`p/;D=?
this.countId=countIds; m[Qr>= "
} iN2591S
public String getCountType(){ i"n1E@
return countType; sfsK[c5bm
} 9-y<= )
public int getCountId(){ Xet}
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return countId; bs)Ro/7}
} R_#k^P^
} ,n$HTWa@0
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CountCache.java P,k=u$
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/* |2I/r$Q
* CountCache.java @`HW0Y_:
* aQV? }
* Created on 2007年1月1日, 下午5:01 KD'}9{F,
* vSk1/
* To change this template, choose Tools | Options and locate the template under S0;s
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* the Source Creation and Management node. Right-click the template and choose cK'}+
* Open. You can then make changes to the template in the Source Editor. ;>Z0e`=
*/ I3 YSW
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package com.tot.count; N^jr
import java.util.*; ;B;wU.Y"
/** ?*cCn-|
* ~ _ko$(;A
* @author && WEBQ
*/ r`PD}6\
public class CountCache { +SkfT4*U
public static LinkedList list=new LinkedList(); MFqb_q+
/** Creates a new instance of CountCache */ P}
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public CountCache() {} 8[oZ>7LMzC
public static void add(CountBean cb){ :PBW=W
if(cb!=null){ m2Wi "X(I_
list.add(cb); 'Kd-A:K2g
} dRBWJ/ 1T
} e)|5P
}
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CountControl.java H2CpZK'
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/* 8B6-f:
* CountThread.java Q 2B
* ex|h&Vma2V
* Created on 2007年1月1日, 下午4:57 #m3!U(Og`
* m|PJwd6
* To change this template, choose Tools | Options and locate the template under =an0PN
* the Source Creation and Management node. Right-click the template and choose c>wne\(5H
* Open. You can then make changes to the template in the Source Editor. v R!
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*/ 4C9k0]k2
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package com.tot.count; ,m5tO
import tot.db.DBUtils; Bm&6
import java.sql.*; ;t4YI7E*
/** "FLiSz%ME
* BxesoB
* @author <6C:\{eo
*/ )%HIC@MM6
public class CountControl{ RT[E$H
private static long lastExecuteTime=0;//上次更新时间 "MyMByomQ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 iXqRX';F'}
/** Creates a new instance of CountThread */ y_2B@cj
public CountControl() {} ym2"D?P
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public synchronized void executeUpdate(){ U=[isi+7
Connection conn=null; lOHW9Z
PreparedStatement ps=null; Y9B"yV
try{ 5)ooE
conn = DBUtils.getConnection(); a&B@F]+
conn.setAutoCommit(false); +(h{3Y|
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $rPQ%2eF4
for(int i=0;i<CountCache.list.size();i++){ 9y j'->dL
CountBean cb=(CountBean)CountCache.list.getFirst(); XjTu`?Na;
CountCache.list.removeFirst(); Xl
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ps.setInt(1, cb.getCountId()); -a7BVEFts
ps.executeUpdate();⑴ d5n>2iO
//ps.addBatch();⑵ lF\2a&YRbn
} S(_DR8
//int [] counts = ps.executeBatch();⑶ EEiWIf&S,
conn.commit(); DDZnNSo<JQ
}catch(Exception e){ 1tl qw
e.printStackTrace(); vZXdc+2l
} finally{ @6H 7
try{ S]Aaf-X_
if(ps!=null) { br*PB]dU
ps.clearParameters(); &5hs
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ps.close(); Uv!VzkPfo
ps=null; rv2;)3/*
} v(P <_}G
}catch(SQLException e){} m1M6N`f
DBUtils.closeConnection(conn); 6+:;Mb_S
} 593!;2/@
} ,Uy;jk
public long getLast(){ rnBp2'EM
return lastExecuteTime; 8(
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} T[2<_ nn=
public void run(){ %I@vM s^
long now = System.currentTimeMillis(); P|TM4i]
if ((now - lastExecuteTime) > executeSep) { /`j2%8^N
//System.out.print("lastExecuteTime:"+lastExecuteTime); |Gr@Mi5
//System.out.print(" now:"+now+"\n"); P[r$KGz
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); TNF
lastExecuteTime=now; \ZBz]rh*
executeUpdate(); \xmDkWzE
} _AH_<Z(
else{ <|hrmwk|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); R0-Y2v
} zO0K*s.yK
} c,#Nd@
} @[{5{ y
//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 rVp^s/A^;
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类写好了,下面是在JSP中如下调用。 (t,mtdD#1
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<% ;Pvnhy
CountBean cb=new CountBean(); 18]Q4s8E
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); EBpg
CountCache.add(cb); HstL'{&,-m
out.print(CountCache.list.size()+"<br>"); h;~NA}>
CountControl c=new CountControl(); +P.JiH`\=
c.run(); l`a_0
out.print(CountCache.list.size()+"<br>"); "e/"$z'ca
%>