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: ([q>.[WbH]
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CountBean.java QIkFX.^
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/* aftt^h
* CountData.java @sn:%/x _
* "Y+VNS
* Created on 2007年1月1日, 下午4:44 `?$-T5Rr
* yT/rH- j;5
* To change this template, choose Tools | Options and locate the template under 7-B|B{]
* the Source Creation and Management node. Right-click the template and choose rB+ (
* Open. You can then make changes to the template in the Source Editor. Hj
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*/ mHMsK}=~
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package com.tot.count; r!!uA1!7
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/** fh =R
* M#^q
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* @author D/=05E%[81
*/ Lmjd,t
public class CountBean { Gk5'|s
private String countType; ]#M"|iTR
int countId; 2*D2jw
/** Creates a new instance of CountData */ F4\:9ws
public CountBean() {} R WY>`.su
public void setCountType(String countTypes){ Bdh*[S\u@E
this.countType=countTypes; -4QZ/ *
} )$^xbC#j`3
public void setCountId(int countIds){ 3/vtx9D
this.countId=countIds; %t&Lq }e
} c(hC'Cp
public String getCountType(){ "T5jz#H#/
return countType; qOG@MR(5
} ByjfPb#
public int getCountId(){ ]B(}^N>WH
return countId; 3|$?T|#B
} RgoF4g+@
} *m"@*O'
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CountCache.java |E K6txRb
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/* +DSbr5"VlB
* CountCache.java )q'dX+4=eL
* w31O~Ve
* Created on 2007年1月1日, 下午5:01 ^kNVQJiZyG
* =Jl\^u%H(x
* To change this template, choose Tools | Options and locate the template under [UkcG9
* the Source Creation and Management node. Right-click the template and choose nycJZ}f:wP
* Open. You can then make changes to the template in the Source Editor. \_.'/<aQ
*/ mL1ZSX
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package com.tot.count; 1W*Qc_5 v1
import java.util.*; ]Yt3@ug_f
/** g s1
* 53uptQ{
* @author T|\sN*}\8J
*/ |u`YT;`!"-
public class CountCache { MDa[bQNM
public static LinkedList list=new LinkedList(); ZOqA8#\
/** Creates a new instance of CountCache */ CxaI@+
public CountCache() {} 7Z]?a
public static void add(CountBean cb){ =z5=?
if(cb!=null){ 0 D4 4
list.add(cb); N''xdz3Z
} D`n<!"xg@$
} d3E N0e+^
} oa+'.b~
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CountControl.java ;Uch
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/* @B{
* CountThread.java fPN/Mxu
* r|Uz?
* Created on 2007年1月1日, 下午4:57 J-=fy^S5
* :D}?H@(69
* To change this template, choose Tools | Options and locate the template under mK M[[l&A
* the Source Creation and Management node. Right-click the template and choose b^i$2$9_
* Open. You can then make changes to the template in the Source Editor. 2FL_!;p;2E
*/ 1;./e&%%
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package com.tot.count; \W_ Dz*N
import tot.db.DBUtils; ++w{)Io Z
import java.sql.*; ~+ae68{p
/** U'b}%[
* LkeYzQH/l
* @author xg%{p``
*/ B7A.~'=
public class CountControl{ :zC=JvKT
private static long lastExecuteTime=0;//上次更新时间 MeV4s%*O+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 i{:?Iw 'ay
/** Creates a new instance of CountThread */ 3|e~YmZx
public CountControl() {} 0* ^f
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public synchronized void executeUpdate(){ :;#^gvH
Connection conn=null; *>iJ=H
PreparedStatement ps=null; M2:3k
try{ l+(B~v
conn = DBUtils.getConnection(); 4cm~oZ
conn.setAutoCommit(false); :'t"kS
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); \py&v5J)s!
for(int i=0;i<CountCache.list.size();i++){ N<(rP1)`v
CountBean cb=(CountBean)CountCache.list.getFirst(); ] %7m+-h@
CountCache.list.removeFirst(); Yo5ged]i
ps.setInt(1, cb.getCountId()); N+R{&v7=F%
ps.executeUpdate();⑴ +CEt:KQ
//ps.addBatch();⑵ #I ,c'Vj
} brE%/%!e
//int [] counts = ps.executeBatch();⑶ !`U #Pjp.
conn.commit(); V[44aN
}catch(Exception e){ 2DZ&g\|
e.printStackTrace(); YS9)%F=X
} finally{ 4wS!g10 }
try{ UT_t]m
if(ps!=null) { 8/"uS ;yP
ps.clearParameters(); Pmuk !V}f
ps.close(); R $/q=*k
ps=null; Nde1`W]:
} Exi#@-
}catch(SQLException e){} >hnhV6ss
DBUtils.closeConnection(conn); O> wGJ.
} 5*"WS $
} ) \cnz
public long getLast(){ }sZy |dd
return lastExecuteTime; bnp:J|(ld
} C`oB [
public void run(){ }D~m%%,
long now = System.currentTimeMillis(); &@&^k$du8q
if ((now - lastExecuteTime) > executeSep) { [eF|2:
//System.out.print("lastExecuteTime:"+lastExecuteTime); Y% [H:
//System.out.print(" now:"+now+"\n"); &6Wim<*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); jN+2+P%OL
lastExecuteTime=now; up3mum
executeUpdate(); D1fUEHB}A8
} )A;jBfr
else{ o5z&sRZ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); v<} $d.&*
} &M\qVL%w
} Wu?[1L:x
} h=cA]^:=
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 a'G[!"
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类写好了,下面是在JSP中如下调用。 ]%5gPfv[T
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<% ciPaCrV
CountBean cb=new CountBean(); KC\W6|NtGj
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); MIv,$
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); 6`'K M/
CountControl c=new CountControl(); kdm@1x
c.run(); 7sJGB^vM
out.print(CountCache.list.size()+"<br>"); n{F&GE="
%>