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: VTdZ&%@
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CountBean.java mB\|<2
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/* qeYr= %)c
* CountData.java [+GG Wo
* &!=3Fbn
* Created on 2007年1月1日, 下午4:44 g;pymz
* CT : ac64
* To change this template, choose Tools | Options and locate the template under |bh:x{h
* the Source Creation and Management node. Right-click the template and choose LY MfoXp
* Open. You can then make changes to the template in the Source Editor. 8V nZ@*
*/ i
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package com.tot.count; $H}Q"^rs
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/** %-dGK)?
* mon(A|$|j
* @author =Ev } v
*/ q b'ka+X
public class CountBean { &uM?DQ`o8
private String countType; dxA=gL2
int countId; wU3Q
/** Creates a new instance of CountData */ Q.
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public CountBean() {} =
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public void setCountType(String countTypes){ ~kL":C>2
this.countType=countTypes; G7yxCU(I\
} 1JM~Ls%Z
public void setCountId(int countIds){ Y9u2:y!LdL
this.countId=countIds; %<klz)!t
} 9Y(<W_{/
public String getCountType(){ lk}x;4]Z
return countType; cg4,PI%hz
} l\eq/yg_
public int getCountId(){ f%af.cR*
return countId; rRMC<.=
} vDemY"wz
} YG% Zw
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CountCache.java qxq ~9\My
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/* {974m` 5
* CountCache.java hOV+}P6
* #Jn_"cCRLx
* Created on 2007年1月1日, 下午5:01 'ySWf,Q^
* 6Z3v]X
* To change this template, choose Tools | Options and locate the template under e&:fzO<~I
* the Source Creation and Management node. Right-click the template and choose +XQ6KG&
* Open. You can then make changes to the template in the Source Editor. #f[yp=uI:
*/ X'5te0v`3
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package com.tot.count; R_lNC]b0
import java.util.*; -V\33cA
/** eI@O9<.&
* c;Li~FLR
* @author (C!fIRY
*/ kAqk~.
public class CountCache { J[9jNCq|
public static LinkedList list=new LinkedList(); OAv/P|n=
/** Creates a new instance of CountCache */ Qtk'^Fc
public CountCache() {} L%"&_v#a^
public static void add(CountBean cb){ /];F4AO5
if(cb!=null){ )2a!EEHz
list.add(cb); &B)
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} Jyd%!v
} Z/64E^
} (T@ov~@
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CountControl.java k&Sg`'LG8
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/* Dv$xP)./
* CountThread.java bBZvL
* JL<}9K
* Created on 2007年1月1日, 下午4:57 {#7t(:x
* {MIs%w.G
* To change this template, choose Tools | Options and locate the template under N@k:kI
* the Source Creation and Management node. Right-click the template and choose U-k6ZV3&8
* Open. You can then make changes to the template in the Source Editor. o;"!#Z 1SJ
*/ M+Dkn3bx
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package com.tot.count; Dgdh3q;
import tot.db.DBUtils; /({5x[
import java.sql.*; VRD2e
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/** HzWZQ6o
* \PL92HV
* @author /6>2,S8Ar
*/ pPh$Jvo]
public class CountControl{ oI^iL\\2h
private static long lastExecuteTime=0;//上次更新时间 t hS#fO4]d
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *G=n${'
/** Creates a new instance of CountThread */ g|W~0A@D
public CountControl() {} r8@:Ko= a
public synchronized void executeUpdate(){ hj-M
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Connection conn=null; E;%{hAD{
PreparedStatement ps=null; 0O[q6!&]
try{ }O_6wi
conn = DBUtils.getConnection(); ,"DkMK4%
conn.setAutoCommit(false); ZV&=B%J bs
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); z2-=fIr.h
for(int i=0;i<CountCache.list.size();i++){ @~zhAU!
CountBean cb=(CountBean)CountCache.list.getFirst();
}UX >O
CountCache.list.removeFirst(); Wkf)4!
ps.setInt(1, cb.getCountId()); !I:6L7HdwB
ps.executeUpdate();⑴ SMnbI.0
//ps.addBatch();⑵ O9!<L.X,%
} :V`q;g
//int [] counts = ps.executeBatch();⑶ w^dB1Y7c(W
conn.commit(); o8bVz2E
}catch(Exception e){ wZ29/{,
e.printStackTrace(); HgbJsv$
} finally{ t0?\5q
try{ X^"95Ic
if(ps!=null) { eGZIdv1
ps.clearParameters(); 5Pn$@3
ps.close(); y9:|}Vh
ps=null; o6'`W2P
} N-lXC"{)
}catch(SQLException e){} xJ,V!N
DBUtils.closeConnection(conn); {<&x9<f9
} T?Gi;ld7
} U%2 pbGU
public long getLast(){ jMg Ni@
return lastExecuteTime; >:8GU f*
} ^8B#-9Ph b
public void run(){ BoFJ8Ukq|
long now = System.currentTimeMillis(); 7HFw*;
if ((now - lastExecuteTime) > executeSep) { oU67<jq
//System.out.print("lastExecuteTime:"+lastExecuteTime); AM\`v'I*6
//System.out.print(" now:"+now+"\n"); nAg|m,gA
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ZcIwyh(`
lastExecuteTime=now; m/CA
executeUpdate(); d[jxU/.p;
} 5'.j+{"
else{ i_ I`Y
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); _8t{4C
} .,-t}5(VSq
} =U2`]50
} RKRk,jRL
//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 }[?X%=
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类写好了,下面是在JSP中如下调用。 ) 3Eax_?Z
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<% pM.>u/=X
CountBean cb=new CountBean(); pl'n
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); izOtt^#DZt
CountCache.add(cb); t4
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out.print(CountCache.list.size()+"<br>"); gy,B+~p
CountControl c=new CountControl(); qJUu9[3'm
c.run(); lfb]xu]O
out.print(CountCache.list.size()+"<br>"); 'lg6<M%#[
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