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: ^Pk-<b4}
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CountBean.java ?Rj)x%fN
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/* _ ecKX</Q
* CountData.java qh)o44/
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* 420cJ{;A
* Created on 2007年1月1日, 下午4:44 dfBTx6/F
* xxh(VQdg
* To change this template, choose Tools | Options and locate the template under U0/X!@F-
* the Source Creation and Management node. Right-click the template and choose g6kVHxh-
* Open. You can then make changes to the template in the Source Editor. Nn],sEs
*/ N| dwuBW
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package com.tot.count; ]_yk,}88d
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/** NyTv~8A`)
* 0b0.xz\~U
* @author &?=UP4[oif
*/ W^Jh'^E
public class CountBean { 5};Nv{km^2
private String countType; )kSE5|:pi
int countId; x7=5 ;gf/X
/** Creates a new instance of CountData */ rQ^$)%uP
public CountBean() {} p}j$p'D.RI
public void setCountType(String countTypes){ DV(^h$1_
this.countType=countTypes; XO*62>Ed
} JR1/\F<}
public void setCountId(int countIds){ 9:!<=rk
this.countId=countIds; P7;=rSW
} (dxkDS-G
public String getCountType(){ (q!tI*}
return countType; |7V:~MTkk&
} Xx~XW^lsh
public int getCountId(){ RSLMO8
return countId; Jp<Y2-
} TixXA:Mf
} t7#C&B
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CountCache.java {]aB3
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/* \h DH81L
* CountCache.java n"'1.
* p-H q\DP
* Created on 2007年1月1日, 下午5:01 ).0h4oHSj
* R!i9N'gGG(
* To change this template, choose Tools | Options and locate the template under $:R"IqDG
* the Source Creation and Management node. Right-click the template and choose \Ze"Hv
* Open. You can then make changes to the template in the Source Editor. `Tx1?]
*/ MX-(;H
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package com.tot.count; Br2ZloJ@+
import java.util.*; -,t2D/xK
/** Q
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* }%B^Vl%ZZ
* @author ~G!>2 +L
*/ F^Yt\V~T
public class CountCache { 15i8) 4h
public static LinkedList list=new LinkedList(); T&Y?IE}
/** Creates a new instance of CountCache */ 3_JxpQg
public CountCache() {} E"e <9
public static void add(CountBean cb){ $=/.oh
if(cb!=null){ 5+<<:5_6l
list.add(cb); $0C1';=^}
}
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} $okGqu8z.O
} 0s"g%gq|
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CountControl.java >z*2Og#1
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/* >qj Q;z[
* CountThread.java v7+f@Z:N*
* `2S G{5o;
* Created on 2007年1月1日, 下午4:57 xyK_1n@b
* /F;b<kIy8
* To change this template, choose Tools | Options and locate the template under 75j`3wzu
* the Source Creation and Management node. Right-click the template and choose '"{ IV
* Open. You can then make changes to the template in the Source Editor. :zk69P3
*/ __\Tv>Y
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package com.tot.count; Aen)r@Y:
import tot.db.DBUtils; u:r'jb~@
import java.sql.*; 1=x4m=wV
/** A ^YHtJ
* i?uJ<BdU[
* @author SG1fu<Q6J
*/ XOQj?Q7)U
public class CountControl{ +~Ni7Dp]
private static long lastExecuteTime=0;//上次更新时间 ^lCys
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ?Xscc mN
/** Creates a new instance of CountThread */ #!d@;=[\
public CountControl() {} <(rf+Ou>I
public synchronized void executeUpdate(){ -I7"9}j3
Connection conn=null; -,NiSh}A
PreparedStatement ps=null; 1s4+a^&
try{ +;7Rz_.6f
conn = DBUtils.getConnection(); 4-@D` ,3L
conn.setAutoCommit(false); Z `FqC
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 9H~3&-8&
for(int i=0;i<CountCache.list.size();i++){ LMchNTL
CountBean cb=(CountBean)CountCache.list.getFirst(); ZzA4iT=KO
CountCache.list.removeFirst(); [,s{ /OM
ps.setInt(1, cb.getCountId()); %xE\IRlR
ps.executeUpdate();⑴ )v&r^DR_
//ps.addBatch();⑵ b&BSigrvou
} *Z*4L|zT
//int [] counts = ps.executeBatch();⑶ d5gYJ/Qv
conn.commit(); ?ic 7M
}catch(Exception e){ &D,gKT~
e.printStackTrace(); (,~gY=E+
} finally{ LFHV~>d
try{ l?:!G7ie
if(ps!=null) { #wH<W5gSZ
ps.clearParameters(); KlbL<9P>
ps.close(); \;
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ps=null; uc@f# (-
} CN6@g^)P
}catch(SQLException e){} :*V1jp+
DBUtils.closeConnection(conn); G<9UL*HU
} 8YJ8_$Z
} qP<wf=wY
public long getLast(){ @N?A0S/
return lastExecuteTime; "71@WLlN
} ,6Ulj+l
public void run(){ A+d&aE}3V
long now = System.currentTimeMillis(); d&n&_>
if ((now - lastExecuteTime) > executeSep) { g3@Qn?(j!
//System.out.print("lastExecuteTime:"+lastExecuteTime); o*7`r ~
//System.out.print(" now:"+now+"\n"); wjGD[~mB
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1A;>@4iC0
lastExecuteTime=now; ^sxcBG
executeUpdate(); |,c\R"8xS
} :d7Ju.*J
else{ `N%q^f~
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); VmM?KlC
} #8P9}WTno.
} d4h1#MK
} n!5 :I#B
//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
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类写好了,下面是在JSP中如下调用。 |IL..C
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<% %dMq'j
CountBean cb=new CountBean(); &UtsI@Mu
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ..RCR_DIp
CountCache.add(cb); MM8r*T4g/
out.print(CountCache.list.size()+"<br>"); }Z5#{Sd
CountControl c=new CountControl(); .^BL7
c.run(); W$=MuF7R
out.print(CountCache.list.size()+"<br>"); C<Q;3w`#1j
%>