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: Y`4 LMK[]
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CountBean.java y0&vsoT
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/* t?PqfVSq
* CountData.java |mbD q\U
* &.s.g\
* Created on 2007年1月1日, 下午4:44 3T,[
* U/cj_}uX
* To change this template, choose Tools | Options and locate the template under 6oZHSjC*
* the Source Creation and Management node. Right-click the template and choose ]o0]i<:
* Open. You can then make changes to the template in the Source Editor. 5kQ@]n:<k
*/ ^?sP[;8S!
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package com.tot.count; nTwJR
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/** = _N[mR^
* qnWM %k
* @author -OU{99$aS
*/ o,c}L9nvt
public class CountBean { }S?"mg&V
private String countType; Z[]8X@IPe
int countId; zF>;7'\x
/** Creates a new instance of CountData */ B]()
public CountBean() {} #>,E"-]f
public void setCountType(String countTypes){ |j9aTv[`
this.countType=countTypes; -\;0gnf{J
} t0@AfO.'1
public void setCountId(int countIds){ Jp}\@T.
this.countId=countIds; Ok{1{EmP
} |:x,|>/
public String getCountType(){ YwF&-~mp7n
return countType; yZ)9Hd
} aT}Hc5L,b
public int getCountId(){ !vpXXI4
return countId; Cj`~ntMN
} <Z.{q Zd
} !QbuOvw
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CountCache.java U.I
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/* \O;/wf0Hg
* CountCache.java qhcx\eD:?
* |&W4Dkn
* Created on 2007年1月1日, 下午5:01 _#&oQFdYR
* c(2?./\|
* To change this template, choose Tools | Options and locate the template under 'bSWJ/;p)
* the Source Creation and Management node. Right-click the template and choose %,HUn`
* Open. You can then make changes to the template in the Source Editor. j3`YaWw
*/ hi/d%lNZ
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package com.tot.count; '7oCWHq[
import java.util.*; ITqAy1m@C
/** GK1nGdT]
* Y*\h?p[,
* @author 8IxIW0
*/ ~xsJML
public class CountCache { "JLE
public static LinkedList list=new LinkedList(); <Lxp t
/** Creates a new instance of CountCache */ w{xa@Q]t-
public CountCache() {} oe|;>0yf
public static void add(CountBean cb){ 4uMMf
if(cb!=null){ An0N'yo"Z
list.add(cb); '\op$t/
} w2X HY>6];
} z[<Na3]
} Bt,'g*Cs
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CountControl.java RN[x\" ,
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/* ,tg]Gt
* CountThread.java $MwBt
* \<T7EV.
* Created on 2007年1月1日, 下午4:57 H?Q--pG8
* hE`d@
* To change this template, choose Tools | Options and locate the template under !z4I-a
* the Source Creation and Management node. Right-click the template and choose sZr \mQ~
* Open. You can then make changes to the template in the Source Editor. }[UH1+`L
*/ pL;e(lM
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package com.tot.count; MD<x{7O12>
import tot.db.DBUtils; n w`rH*
import java.sql.*; YsVKdh
/** cNmAr8^}
* quaRVD>s +
* @author '<<@@.(f
*/ {^N,$,Ab.
public class CountControl{ O#18a,o@
private static long lastExecuteTime=0;//上次更新时间 DeNWh2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Fv
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/** Creates a new instance of CountThread */ ?6&G:Uz/
public CountControl() {} KGo^>us
public synchronized void executeUpdate(){ 8,[ *BgeX
Connection conn=null; $b{8$<;9
PreparedStatement ps=null; JU5,\3Lz#
try{ <X4f2z{T{@
conn = DBUtils.getConnection(); H!X*29nX
conn.setAutoCommit(false); W5Pur
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); HpIi- Es7C
for(int i=0;i<CountCache.list.size();i++){ ILH[q>
CountBean cb=(CountBean)CountCache.list.getFirst(); 5EI"5&`*
CountCache.list.removeFirst(); WTl0}wi
ps.setInt(1, cb.getCountId()); SSE,G!@
ps.executeUpdate();⑴ a*D<J}xe
//ps.addBatch();⑵ U;
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} uuF~+=.|
//int [] counts = ps.executeBatch();⑶ W% Lrp{
conn.commit(); =EA @
}catch(Exception e){ {Ke
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e.printStackTrace(); 2YWO'PL
} finally{ qM26:kB{
try{ Pp69|lxV=k
if(ps!=null) { SnXM`v,
ps.clearParameters(); >.od(Fh{l|
ps.close(); G9QvIXRi
ps=null; Ax~
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} Q#ksf
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}catch(SQLException e){} DA>nYj-s
DBUtils.closeConnection(conn); *?uUP
} ;'V[8`Z@
} MMET^SO
public long getLast(){ AI{0;0
return lastExecuteTime;
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} c1+z(NQ3
public void run(){ iiJT%Zq`#
long now = System.currentTimeMillis(); y $uq`FW
if ((now - lastExecuteTime) > executeSep) { C Q iHk
//System.out.print("lastExecuteTime:"+lastExecuteTime); UukY9n];]
//System.out.print(" now:"+now+"\n"); noa+h<vGb
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); r1RM7y
lastExecuteTime=now; =+T0[|gc(r
executeUpdate(); ,98 F
} o_Y?s+~i[/
else{ VZ`YbY
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); wG)[Ik6:
} mdrqX<x'~
} uTrzC+\aU
} aCQ[Uc<B:
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 b3%a4Gg&
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类写好了,下面是在JSP中如下调用。 uBg#zx
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<% lnjs{`^
CountBean cb=new CountBean(); o(l%k},a
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )AdwA+-x
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); tCR~z1
CountControl c=new CountControl(); r<srTHGLo
c.run(); ^*$!9~
out.print(CountCache.list.size()+"<br>"); IV':sNV
%>