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: wrabyRjK
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CountBean.java @7fm1b
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/* jP+ pA e
* CountData.java 2)=la%Nx
* G)8ChnJa!m
* Created on 2007年1月1日, 下午4:44 vnTq6:f#M
* kQIfYtT
* To change this template, choose Tools | Options and locate the template under .A(i=!{q
* the Source Creation and Management node. Right-click the template and choose |:N>8%@6c
* Open. You can then make changes to the template in the Source Editor. *
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*/ 9s(i`RTM
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package com.tot.count; Rjq a_hxrS
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/** yc[(lq.^n
* g,=^'D
* @author ;T>+,
*/ &L%Jy #=
public class CountBean { ;gUXvx~~r
private String countType; 8 aZ$5^z
int countId; Pxqiv9D<R
/** Creates a new instance of CountData */ =-Nsc1&
public CountBean() {} ~,gLplpG0
public void setCountType(String countTypes){ HxZ.OZbR
this.countType=countTypes; TY~Vi OC
} +;dXDZ2
public void setCountId(int countIds){ 1q]&7R
this.countId=countIds; uH\w.
} ddoFaQ8
public String getCountType(){ 5,R`@&K3D
return countType; 1%jH^,t/m
} DT\ym9
public int getCountId(){ nv)))I\
return countId; J(e7{aRJ9
} hg8Be6G<
} DvYwCgLR
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CountCache.java +ubnx{VC
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/* nvt$F%+
* CountCache.java Xu#:Fe}:
* VoM6
* Created on 2007年1月1日, 下午5:01 Sy
* . :a<2sp6
* To change this template, choose Tools | Options and locate the template under |` "?
* the Source Creation and Management node. Right-click the template and choose 2m" _z
* Open. You can then make changes to the template in the Source Editor. \ha-"Aqze3
*/ gu<V(M\
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package com.tot.count; $;`I,k$0>~
import java.util.*; =X@o@1
/** =|,A%ZGF$
* =cn~BnowY
* @author 41yOXy ;~l
*/ 0x ~`5h
public class CountCache { ^A!$i$NON
public static LinkedList list=new LinkedList(); `WnQ
/** Creates a new instance of CountCache */ smup,RNZRX
public CountCache() {} cDeZMsV
public static void add(CountBean cb){ utH%y\NMF|
if(cb!=null){ S-!=NX&C
list.add(cb); 0
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} "hPCQp`Tj
} 6/1$<!WH
} V`bs&5#Sx
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CountControl.java 7ZsA5%s=,
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/* Y(r@v
* CountThread.java 'N6 S}w7
* $r79n-
* Created on 2007年1月1日, 下午4:57 /oL8;:m
* y@;%Uv&
* To change this template, choose Tools | Options and locate the template under O('Nn]wo~9
* the Source Creation and Management node. Right-click the template and choose 9M'DC^x*T
* Open. You can then make changes to the template in the Source Editor. EB,4PEe:
*/ 1'O0`Me>#
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package com.tot.count; Uu'dv#4Iw
import tot.db.DBUtils; <3Gqv9Y&
import java.sql.*; :=fvZA WD
/** iM5vrz`n
* hs(W;tR@W
* @author ; LMWNy4
*/ Wi$dZOcSJ
public class CountControl{ FjFwvO_.
private static long lastExecuteTime=0;//上次更新时间 .Dw,"VHP
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~xDw*AC-
/** Creates a new instance of CountThread */ x_!ZycEa
public CountControl() {} z<&m*0WYA
public synchronized void executeUpdate(){ Lh ap4:
Connection conn=null; /!T> b:0
PreparedStatement ps=null; SlaDt
try{ CDdkoajBa
conn = DBUtils.getConnection(); A'-_TFwW
conn.setAutoCommit(false); c\.P/~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Fn+?u
for(int i=0;i<CountCache.list.size();i++){ v}[dnG
CountBean cb=(CountBean)CountCache.list.getFirst(); &leK}je [
CountCache.list.removeFirst(); ,}J_:\j
ps.setInt(1, cb.getCountId()); 50n}my'2h
ps.executeUpdate();⑴ z-,VnhLx
//ps.addBatch();⑵ qSD9P ue
} \ZH&LPAY
//int [] counts = ps.executeBatch();⑶ qZ X/@Yxz
conn.commit(); GwLFL.Ke
}catch(Exception e){ o#D.9K(
e.printStackTrace(); JhX=l-?
} finally{ yI)~]K
r
try{ 6rX_-Mm6w
if(ps!=null) { s>%Pd7:
ps.clearParameters(); jd:B \%#![
ps.close(); 1RqgMMJL
ps=null; ,t,wy37*D
} FWY2s(5p
}catch(SQLException e){} IIz0m3';+
DBUtils.closeConnection(conn); }roG(
} {{!Y]\2S
} rU2iy"L
public long getLast(){ kWW w<cA
return lastExecuteTime; Q6'nSBi:A_
} a07=tD
public void run(){ ll<NIdf\r
long now = System.currentTimeMillis(); 76H!)={
if ((now - lastExecuteTime) > executeSep) { .p&Yr%~
//System.out.print("lastExecuteTime:"+lastExecuteTime); z"
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//System.out.print(" now:"+now+"\n"); ]Pc^#=(R0
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); io%')0p5q
lastExecuteTime=now; IL!=mZ>2O
executeUpdate(); kXc25y'blP
} Q0cRH"!:
else{ lE5v-z? &|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ..<3%fL3
} XL5Es:"+?S
} 0 f/.>1M=
} H0*,8i5I
//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 @pza>^wk
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类写好了,下面是在JSP中如下调用。 v:|(8Y
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<% .$rC0<G[K
CountBean cb=new CountBean(); ra6o>lI(,
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); uTvv(f
CountCache.add(cb); K_/B?h
out.print(CountCache.list.size()+"<br>"); SO?8%s(
CountControl c=new CountControl(); Is.WZYa
c.run(); 0l\y.
out.print(CountCache.list.size()+"<br>"); %NARyz
%>