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: }Pi}?
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CountBean.java w3hG\2)[HS
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/* ^@91BY
* CountData.java "XKcbdr8-
* $TU:iv1Fm
* Created on 2007年1月1日, 下午4:44 Q[rmsk2L'
* PMOyZ3
* To change this template, choose Tools | Options and locate the template under YCBp]xuE
* the Source Creation and Management node. Right-click the template and choose Y\7WCaSgi
* Open. You can then make changes to the template in the Source Editor. LIah'6qR
*/ {Q?\%4>2
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package com.tot.count; oItEGJ|
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/** \US'tF)/
* 62s0$vw
* @author e-&0f);i
*/ |.]g&m)y^h
public class CountBean { FdwlRu G
private String countType; G~.bi<(v
int countId; i>elK<R4
/** Creates a new instance of CountData */ PxAUsY
public CountBean() {} 4Su|aWL-
public void setCountType(String countTypes){ KU;d[Z@g
this.countType=countTypes; V1l9T_;f
} gdj,e ^
public void setCountId(int countIds){ b79z<D
this.countId=countIds; E]MyP=g$
} xZ\`f-zL
public String getCountType(){ r
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return countType; $bo,m2)
} \I-bZ|^
public int getCountId(){ V;N'?Gu
return countId; PR+L6DT_
} 7my7|s[
} ;o#wK>pk%M
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CountCache.java B5R/GV
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/* 7 'B9z/
* CountCache.java }57d3s
* (_ TKDx_
* Created on 2007年1月1日, 下午5:01 qA;!Pql`
* y+aL5$x6
* To change this template, choose Tools | Options and locate the template under UL3++bt
* the Source Creation and Management node. Right-click the template and choose c{(4s6D
* Open. You can then make changes to the template in the Source Editor. Bk
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*/ KlbUs\E
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package com.tot.count; P`$Y73L
import java.util.*; FfSKE
/** L"x9O'U
* TBU.%3dEyI
* @author uP.[,V0@^
*/ :c/](M
public class CountCache { o0B3G
public static LinkedList list=new LinkedList(); UmNh0nS
/** Creates a new instance of CountCache */ g[D`.
public CountCache() {} }"\jB
public static void add(CountBean cb){ u^X,ASkQ
if(cb!=null){ a?
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list.add(cb); eb*w$|y6"
} n38l!m(.
} o|njgmF;\
} 8]2j*e0xV
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CountControl.java wK*b2r}0/
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/* ,!I'0x1OR
* CountThread.java Y(97},
* i-W!`1LH'
* Created on 2007年1月1日, 下午4:57 6$'0^Ftm'
* oc0z1u
* To change this template, choose Tools | Options and locate the template under LVAnZ'h/|
* the Source Creation and Management node. Right-click the template and choose iJ%`ym4Y
* Open. You can then make changes to the template in the Source Editor. XJ*W7HD
*/ :ySQ[AJ"
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package com.tot.count; #- z(]Y,y
import tot.db.DBUtils; @'lO~i
import java.sql.*; no
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/** R1j)0b6cQ%
* R2B0?fu
* @author =>u9k:('9
*/ ];7/DM#Np
public class CountControl{ X)^&5;\`
private static long lastExecuteTime=0;//上次更新时间 \CK f/:"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 MU#$tXmnC
/** Creates a new instance of CountThread */ \+I+Lrj%
public CountControl() {} -)o0P\cTEt
public synchronized void executeUpdate(){ $8t\|O3
Connection conn=null; ?YA5g' l
PreparedStatement ps=null; t=6Wk4
try{ SHt#%3EU
conn = DBUtils.getConnection(); 8pE0ANbq
conn.setAutoCommit(false); ZnXq+^Z4
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); jPyhn8Vw
for(int i=0;i<CountCache.list.size();i++){ KX $Q`lM
CountBean cb=(CountBean)CountCache.list.getFirst(); 'X]my
CountCache.list.removeFirst(); ndxijqw
ps.setInt(1, cb.getCountId()); wJb"X=i*
ps.executeUpdate();⑴ y|O)i
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//ps.addBatch();⑵ @K}8zMmW#
} >^V3Z{;
//int [] counts = ps.executeBatch();⑶ +f]\>{o4
conn.commit(); lBcRt)_O7
}catch(Exception e){ qcdENIy0b
e.printStackTrace(); ]>'yt #]
} finally{ 1Yb9ILX[J
try{ |@lVFEl]
if(ps!=null) { $" `9QD~
ps.clearParameters(); Mz:t[rfs
ps.close(); r\f|r$i
ps=null; WC
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} uL[%R2
}catch(SQLException e){} :1(UC}v
DBUtils.closeConnection(conn); uom~,k$|
} /ar/4\b
} ;x~[om21;
public long getLast(){ 4}>1I}!k
return lastExecuteTime; HZ.Jc"+M
} |&xjuBC
public void run(){ y|0I3n]e
long now = System.currentTimeMillis(); D-!#TN`Y
if ((now - lastExecuteTime) > executeSep) { j6.'7f5M<H
//System.out.print("lastExecuteTime:"+lastExecuteTime); PdNxuy
//System.out.print(" now:"+now+"\n"); $v*0\O
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); YTo^Q&
lastExecuteTime=now; 5q>u]n9]
executeUpdate(); Zd]2>h
} OcLFVD=
else{ 7IV:X
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 9e xHR&>{
} i@|.1dWh
} xgQ]#{tG
} | Sf` Cs
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ^FZ7)T
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类写好了,下面是在JSP中如下调用。 zMI0W&P M
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<% OJH:k~]0!
CountBean cb=new CountBean(); 5NECb4FG
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); oL69w1
CountCache.add(cb); +iL,8eW
out.print(CountCache.list.size()+"<br>"); p<9e5`&I
CountControl c=new CountControl(); Y><")% Q
c.run(); 1>1ii
out.print(CountCache.list.size()+"<br>"); !1M=9 ~$!
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