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: ht7l- AK
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CountBean.java ;QWIsVz
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/* BD68$y
* CountData.java @"hb) 8ng
* nePfuG]Q
* Created on 2007年1月1日, 下午4:44 5*E]ETo@R
* kEJj=wx
* To change this template, choose Tools | Options and locate the template under .GV;+8HzS
* the Source Creation and Management node. Right-click the template and choose zepm!JR1
* Open. You can then make changes to the template in the Source Editor. x%}^hiO<q
*/ ,">]`|?
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package com.tot.count; {`J)j6;
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/** 7/!8e.M\
* 'r4/e-`pK
* @author ]*vdSr-J
*/ j`oy`78O
public class CountBean { tU4s'J
private String countType; 3XL#0\im?s
int countId; \Npxv
/** Creates a new instance of CountData */ mIurA?&7!
public CountBean() {} ^]7}YF2|
public void setCountType(String countTypes){ (^s>m,h
this.countType=countTypes; O9vQp
} 9G9fDG#F\I
public void setCountId(int countIds){ "k/;[ Wt]
this.countId=countIds; w0ht
} S)lkz'tdk
public String getCountType(){ #EO9UW5
return countType; t=|evOz]
} (gy#js#
public int getCountId(){ &{ay=Mj
return countId; 5XO;N s
} T29Dt
} YX=a#%vrl
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CountCache.java 3_txg>P"
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/* tro7Di2Q
* CountCache.java ?h.wK
* M%Ji0v38
* Created on 2007年1月1日, 下午5:01 G]D+Sl4<7i
* [f)cL6AeF
* To change this template, choose Tools | Options and locate the template under \!>3SKs(e
* the Source Creation and Management node. Right-click the template and choose *#E
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* Open. You can then make changes to the template in the Source Editor. cU;iUf
*/ }M1`di4e
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package com.tot.count; Ge2q%
import java.util.*; Z8zmHc"IH
/** ]or>?{4g
* cJN7bA{
* @author XaCX!Lr,
*/ PRr2F-!P
public class CountCache { ]gmexa=(i
public static LinkedList list=new LinkedList(); xgbJ2Mh
/** Creates a new instance of CountCache */ ^=T$&gD
public CountCache() {} g,}_G3[j0m
public static void add(CountBean cb){ pi /g H
if(cb!=null){ ;-9=RI0
list.add(cb); $eD.W
} qm./|#m>
} EKA#|^Q:NX
} cVubb}ou
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CountControl.java s8-<m,*
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/* uxW~uEh
* CountThread.java .P;*D ws
* KB%"bqB|
* Created on 2007年1月1日, 下午4:57 /s?r`' j[
* %`OJ.:k
* To change this template, choose Tools | Options and locate the template under }E0,z
* the Source Creation and Management node. Right-click the template and choose .Si,dc\
* Open. You can then make changes to the template in the Source Editor. )0ea+ib
*/ (5#nrF]
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package com.tot.count; N03HQp)g
import tot.db.DBUtils; 2r!s*b\Ix
import java.sql.*; ,a gc
/** !_`&Wks
* 9F4Dm*_<
* @author <\Eh1[F
*/ 'ixwD^x
public class CountControl{ E}Y!O"CAV
private static long lastExecuteTime=0;//上次更新时间 )f}YW/'
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 "B=
/** Creates a new instance of CountThread */ }!;s.[y
public CountControl() {} ?3%`bY+3;
public synchronized void executeUpdate(){ %ZNI:Uh
Connection conn=null; XM1WfjE\
PreparedStatement ps=null; Z3{>yYR+
try{ 7Bb9t
conn = DBUtils.getConnection(); v5By :z
conn.setAutoCommit(false); Av"R[)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "$N#p5
for(int i=0;i<CountCache.list.size();i++){ ;u;# g
CountBean cb=(CountBean)CountCache.list.getFirst(); qR(\5}
CountCache.list.removeFirst(); (IC]?n}
ps.setInt(1, cb.getCountId()); <<(wa
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ps.executeUpdate();⑴ "SzdDY6
//ps.addBatch();⑵ 8S%52W|
} MZlk0o2
//int [] counts = ps.executeBatch();⑶ 9/hrjItV
conn.commit(); OlAs'TE^
}catch(Exception e){ Q?3Gk%T0[
e.printStackTrace(); *"D3E7AO
} finally{ 5"HVBfFk
try{ ?*E'^~,H)
if(ps!=null) { t"k*PA
ps.clearParameters(); -M[$Z y^
ps.close(); G]fRk^~
ps=null; 29!q!g |
} MO&}r7qq
}catch(SQLException e){} odPL{XFj
DBUtils.closeConnection(conn); -sw
.
} \<y`!"c
} Fe]B&n
public long getLast(){ W.dt:_
return lastExecuteTime; Rn{iaM2Y<
} {P{bOe
public void run(){ V>R8GSx
long now = System.currentTimeMillis(); [* @5\NWR}
if ((now - lastExecuteTime) > executeSep) { c.,2GwW
//System.out.print("lastExecuteTime:"+lastExecuteTime); NXNY"r7~
//System.out.print(" now:"+now+"\n"); ^zt-HDBR_
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {.QEc0-
lastExecuteTime=now; @$LWWTr;
executeUpdate(); AI,(z;{P
} Sg6"WV{<
else{ "Jt.lL ]5
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 4zJtOK?r"
} }"=AG
} "NgxkbDEbG
} tcLnN:
//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 LXEfPLS
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类写好了,下面是在JSP中如下调用。 qjf[zF
} w
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<% ?RK]FP"A
CountBean cb=new CountBean(); HRiL.DS
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); H2um|6>
CountCache.add(cb); 7Garnd b
out.print(CountCache.list.size()+"<br>"); dgA-MQ5{
CountControl c=new CountControl(); JcbwDlUb
c.run();
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out.print(CountCache.list.size()+"<br>"); Eo#u#IY
%>