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: sF7^qrVQP9
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CountBean.java d oB
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/* &
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* CountData.java %J8|zKT5t
* r@{~ 5&L
* Created on 2007年1月1日, 下午4:44 ^+
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* {<5ybbhLV
* To change this template, choose Tools | Options and locate the template under Dk='+\
* the Source Creation and Management node. Right-click the template and choose sO5?aB&
* Open. You can then make changes to the template in the Source Editor. J-ePE7i
*/ o=RM-tR`v
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package com.tot.count; 'oN\hy($,h
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/** >j{z>
* 6&!&\
* @author NWd<+-pC6
*/ 4Td{;Y="yF
public class CountBean { :aG#~-Q
private String countType; 5'Q|EIL
int countId; af|5n><~A
/** Creates a new instance of CountData */ ]7Fs$y.
public CountBean() {} NO]
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public void setCountType(String countTypes){ siTX_`0
this.countType=countTypes; St<mDTi
} .@"q$\
public void setCountId(int countIds){ g!i45-n3gt
this.countId=countIds; <jS~ WI@
} 5~.ZlGd
public String getCountType(){ unJ R=~E
return countType; 0A:n0[V:]
} fGv#s
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public int getCountId(){ zFQ&5@43
return countId; #XnPsU<J
} $o +5/c?|
} 2Sq_Tw3^
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CountCache.java n9;;x%6 .I
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/* huudBc
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* CountCache.java &vovA} F
* [DHoGy,P
* Created on 2007年1月1日, 下午5:01 63!rUB!
* ?+c`]gO7N
* To change this template, choose Tools | Options and locate the template under ~O 3D[PNW~
* the Source Creation and Management node. Right-click the template and choose xvNo(>
* Open. You can then make changes to the template in the Source Editor. {"vkji>
*/ W-
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package com.tot.count; NWfAxkz{/
import java.util.*; ?k[p<Uo
/** 3M0+"l(X
* \7z^!m
* @author
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*/ =H8 xSJLh
public class CountCache { 4gSH(*}
public static LinkedList list=new LinkedList(); b.O9ITR
/** Creates a new instance of CountCache */ [~\PQYm'
public CountCache() {} CU:o*;jP
public static void add(CountBean cb){ :y2p@#l#
if(cb!=null){ +uWYK9
list.add(cb); $hR)i
} =TP(
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} FA90`VOWYU
} ]0B|V2D#e
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CountControl.java >O/D!j|
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/* }<jb vCeK
* CountThread.java dP]1tAO,y
* { m8+Wju}
* Created on 2007年1月1日, 下午4:57 K={qU[_O
* ZAuWx@}
* To change this template, choose Tools | Options and locate the template under qpJ{2Q
* the Source Creation and Management node. Right-click the template and choose t!1$$e?`r
* Open. You can then make changes to the template in the Source Editor. nH !3(X*
*/ $ XBAZ<"hd
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package com.tot.count; U"f??y%)
import tot.db.DBUtils; fQnwy!-\
import java.sql.*; sP'0Sl~NU
/** c~<1':
* $[@0^IJq=K
* @author hIJ)MZU|
*/ QO{y/{
public class CountControl{ -V %gVI[
private static long lastExecuteTime=0;//上次更新时间 0(8H;T
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ?y XAu0
/** Creates a new instance of CountThread */ ftk%EYT;
public CountControl() {} Oq(VvS/
public synchronized void executeUpdate(){
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Connection conn=null; _kFYBd
PreparedStatement ps=null; [O
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try{ 6qo^2
conn = DBUtils.getConnection(); >cL{Ya}Rz
conn.setAutoCommit(false); DZ
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); s]27l3)B
for(int i=0;i<CountCache.list.size();i++){ HjWq[[Nz
CountBean cb=(CountBean)CountCache.list.getFirst(); W</n=D<,I
CountCache.list.removeFirst(); t j Vh^
ps.setInt(1, cb.getCountId()); VyG4(Xva
ps.executeUpdate();⑴ Z<b"`ty.
//ps.addBatch();⑵ \nrP$
} Q}A=jew
//int [] counts = ps.executeBatch();⑶ t@?u
conn.commit(); UFn8kBk
}catch(Exception e){ 3b[jwCt
e.printStackTrace(); |4Ck;gg!j
} finally{ !wLg67X$
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try{ k /EDc533d
if(ps!=null) { %bb~Y"
ps.clearParameters(); VY 1vXM3y
ps.close(); qBk``!|s]
ps=null; oCi
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} CPazEe1S
}catch(SQLException e){} |-2}j2'
DBUtils.closeConnection(conn); IF
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} t@bt6J .{
} `BZ&~vJ_
public long getLast(){ |I[7,`C~
return lastExecuteTime; }UyQ# U
} 3mt%!}S
public void run(){ 6\dX
long now = System.currentTimeMillis(); )E7 FA|
if ((now - lastExecuteTime) > executeSep) { T9y;OG
//System.out.print("lastExecuteTime:"+lastExecuteTime); ZX`J8lZP
//System.out.print(" now:"+now+"\n"); ^DAa%u
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); u>T76,8|\
lastExecuteTime=now; QYE7p\
executeUpdate(); {GqXP0'
} U Lmg$T&
else{ U!q[e`B
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); S9Y[4*//
} YwT-T,oD
} 5a8>g
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} \Xg?Ug*9w
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 y)J(K*x/$
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类写好了,下面是在JSP中如下调用。 =F%RLpNU4
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<% 3=4SGt5m
CountBean cb=new CountBean(); mU{4g`Iw
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Nofu7xiDw[
CountCache.add(cb); ?H;{~n?
out.print(CountCache.list.size()+"<br>"); 8LM#WIm?
CountControl c=new CountControl(); !)OB@F%U
c.run(); /nB'kg[h\
out.print(CountCache.list.size()+"<br>"); uOk%AL>
%>