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: Frml'Vfq7
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CountBean.java ij TtyTC
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/* R%Z} J R.
* CountData.java &Ls0!dWC
* sJD"u4#y
* Created on 2007年1月1日, 下午4:44 d.
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* oqE
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* To change this template, choose Tools | Options and locate the template under w &-r
* the Source Creation and Management node. Right-click the template and choose saZ;ixV
* Open. You can then make changes to the template in the Source Editor. '%MIG88
*/ lz( 9pz
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package com.tot.count; xs:{%ki
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/** X bg7mj9c
* t
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* @author 2c~^|@
*/ 9\;EX
public class CountBean { 9qPP{K,Pq2
private String countType; M|Se|*w
int countId; 6y0C
/** Creates a new instance of CountData */
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public CountBean() {} =SdWU}xn2
public void setCountType(String countTypes){ 4$J/e?i
this.countType=countTypes; u+V;r)J{
} / [19ITZ
public void setCountId(int countIds){ :DD4BY
this.countId=countIds; Nr)(&c8
} vxgm0ZOMN
public String getCountType(){ `+gF|o9
return countType; 3aOFpCs|#
} 5x: XXj"
public int getCountId(){ nMnc&8r
return countId; 0uvL,hF
} zqeU>V~<F
} >5j/4Ly
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CountCache.java /t/q$X
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/* cnj_tC=zt
* CountCache.java gV7o
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* RS1oPY
* Created on 2007年1月1日, 下午5:01 Yv;aQF"a
* M}vPWWcl
* To change this template, choose Tools | Options and locate the template under :K~7BJ(HO
* the Source Creation and Management node. Right-click the template and choose i6-K!
* Open. You can then make changes to the template in the Source Editor. &yN<@.
*/ =_86{wlk
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package com.tot.count; 0eLK9u3<
import java.util.*; 7-LeJRB
/** Xu$*ZJ5w
* NX;&V7
* @author 4{R`
*/ '*k\IM{h
public class CountCache { i!iODt3k
public static LinkedList list=new LinkedList(); Ob+&!XTp?0
/** Creates a new instance of CountCache */ 9D<HJ(
public CountCache() {} 3k/MigT
public static void add(CountBean cb){ #7>CLjI
if(cb!=null){ |RmBa'.)z
list.add(cb); $_VD@YlAp
} t|q=NK/
} YU`{
} l\5NuCgRY
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CountControl.java r:IU+3
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/* 4D13K.h`O
* CountThread.java :o:??tqw
* @^ e@.)
* Created on 2007年1月1日, 下午4:57 J]UHq$B
* ?,NAihN]
* To change this template, choose Tools | Options and locate the template under kr?|>6?
* the Source Creation and Management node. Right-click the template and choose tFwlx3
* Open. You can then make changes to the template in the Source Editor. L:<'TXsRA
*/ P#xn!fMi
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package com.tot.count; 5"Yw$DB9
import tot.db.DBUtils; nAzr!$qbNv
import java.sql.*; D.!4i.)8}
/** \9p;md`
* fCfY.vd5
* @author ~I<y^]2{
*/ sF$m?/Kt
public class CountControl{ UXP;'
private static long lastExecuteTime=0;//上次更新时间 lySa Jd
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 [wR8q,2
/** Creates a new instance of CountThread */ R4/@dA0
public CountControl() {} U*@_T 3N
public synchronized void executeUpdate(){ 8`2K=`]ES+
Connection conn=null; eG v"&kr
PreparedStatement ps=null; [OcD#~drO
try{ =Vs<DO{|4q
conn = DBUtils.getConnection(); d1-p];&
conn.setAutoCommit(false); #t
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >U)O@W)
for(int i=0;i<CountCache.list.size();i++){ #vSI_rt9I
CountBean cb=(CountBean)CountCache.list.getFirst(); BP6Shc|C
CountCache.list.removeFirst(); Fo#*_y5\
ps.setInt(1, cb.getCountId()); +[ zo2lBx
ps.executeUpdate();⑴
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//ps.addBatch();⑵ kQ8WO|bA
} W}RR_Gu
//int [] counts = ps.executeBatch();⑶ ;qMlGXW*q
conn.commit(); A=K1T]o
}catch(Exception e){ #7=LI\
e.printStackTrace(); fW
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} finally{ Q1Ao65
try{ 7 SZR#L
if(ps!=null) { GLyh1qNX
ps.clearParameters(); R 6Em^A/>
ps.close(); BXY'%8q _a
ps=null; _SqrQ
} ;Y\,2b, xh
}catch(SQLException e){} $b} +5
DBUtils.closeConnection(conn); qE}YVKV*
} M6iKl
} 5MJ'/Fy(
public long getLast(){ %Qq)=J<H;
return lastExecuteTime; U4gJ![>5j
} ny= {V*m
public void run(){ S41>VbtEp
long now = System.currentTimeMillis(); S<~nk-xr*h
if ((now - lastExecuteTime) > executeSep) { h.0K
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//System.out.print("lastExecuteTime:"+lastExecuteTime); #EUgb7
//System.out.print(" now:"+now+"\n"); *q{UipZbx
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); qgNK!(kWpr
lastExecuteTime=now; =*jcO119L
executeUpdate(); U5"Oh I
} &v,p_'k
else{ '9@R=#nd
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ?miM15XI
} OWsYE?
} [<QWTMjR
} Umg81!
//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 dL(|Y{4
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类写好了,下面是在JSP中如下调用。 ISew]R2
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<% MFuI&u!g:
CountBean cb=new CountBean(); 4a!7|}W
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Z"X*FzFo
CountCache.add(cb); o"[bIXf-h
out.print(CountCache.list.size()+"<br>"); >N-%
CountControl c=new CountControl(); )AXH^&
c.run(); :g#it@
out.print(CountCache.list.size()+"<br>"); NCt sx /C
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