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: #W!@j"8eK
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CountBean.java ZIpL4y
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/* lm]4zs /A
* CountData.java MK~viSgi
* /p X\)wi
* Created on 2007年1月1日, 下午4:44 e:!&y\'"9
* t55
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* To change this template, choose Tools | Options and locate the template under 0QEVL6gw
* the Source Creation and Management node. Right-click the template and choose U.?,vw'aai
* Open. You can then make changes to the template in the Source Editor. 7M^!t X
*/ ;wTl#\|w0
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package com.tot.count; oryoGy=(yk
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/** HAN#_B1.
* `C] t2^
* @author QXgh[9wG
*/ =$Xdn'
public class CountBean { $Wb"X=}tl
private String countType; cq@8!Eu w]
int countId; h7I_{v8
/** Creates a new instance of CountData */ qrm~=yU%
public CountBean() {} mpXco *!_
public void setCountType(String countTypes){ Ay2Vz>{
this.countType=countTypes; Tfs7SC8ta
} pS*vwYA
public void setCountId(int countIds){ HPr5mWs:
this.countId=countIds; $S=lm {
} [T~O%ly7x&
public String getCountType(){ 2x3&o|J
return countType; p# O%<S@?
} H4^-M Sw
public int getCountId(){ X^fMt]
return countId; }MXZ
} yv4hH4Io
} ldi'@^
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CountCache.java R}>Gk
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/* uK}k]x\z
* CountCache.java duT2:~H2
* ihf5`mk/$
* Created on 2007年1月1日, 下午5:01 0=L:8&m
* |2{y'?,
* To change this template, choose Tools | Options and locate the template under Mq6.!j
* the Source Creation and Management node. Right-click the template and choose .CrahV1G
* Open. You can then make changes to the template in the Source Editor. :m^eNS6:
*/ C!RxMccTh
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package com.tot.count; im4V6 f;%
import java.util.*; YX!%R]c%
/** Aw9^}k}UfD
* 1&Nk
* @author 4vp,izNW
*/ _@jl9<t=_
public class CountCache { lj'c0k8
public static LinkedList list=new LinkedList(); )#IiHBF
/** Creates a new instance of CountCache */ xREqcH,vU
public CountCache() {} @6}c\z@AxM
public static void add(CountBean cb){ FU5vo
if(cb!=null){ |UBR8
list.add(cb); !-LPFy>
} &Q(Q/]U~
} s26:(J
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} 9IC"p<D
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CountControl.java >vt#,8VAN
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/* y{U'\
* CountThread.java "7Zb)Ocb
* %HwPOEJ
* Created on 2007年1月1日, 下午4:57 'hf-)\Ylf
* yi
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* To change this template, choose Tools | Options and locate the template under r3_@ L>;
* the Source Creation and Management node. Right-click the template and choose lNls8@
* Open. You can then make changes to the template in the Source Editor. L?4c8!Q
*/ nWmc
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package com.tot.count; mNWmp_c,1
import tot.db.DBUtils; @H1pPr
import java.sql.*; jYO@ %bQ
/** L7%Dc2{^(
* $2 ~A^#"0
* @author >umcpkp-h
*/ )Xl/|YD
public class CountControl{
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private static long lastExecuteTime=0;//上次更新时间 y<8)mw
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 R%8nR6iG"
/** Creates a new instance of CountThread */ 9I+;waLlB
public CountControl() {} YJ.'Yc
public synchronized void executeUpdate(){ #B;` T[
Connection conn=null; -"<H$
PreparedStatement ps=null; Yg<o 9x$
try{ @C~TD)K
conn = DBUtils.getConnection(); N[){yaj
conn.setAutoCommit(false); >c5Vz^uM{4
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); LL#7oBJdM
for(int i=0;i<CountCache.list.size();i++){ gO gZ
CountBean cb=(CountBean)CountCache.list.getFirst(); MU-ie*+
CountCache.list.removeFirst(); Xr6lYO _R
ps.setInt(1, cb.getCountId()); 9 qqy( H
ps.executeUpdate();⑴ 'O
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//ps.addBatch();⑵ v9u/<w68!
} ~EpMO]I
//int [] counts = ps.executeBatch();⑶ E9!IGci
conn.commit(); ofj7$se
}catch(Exception e){ g@`14U/|
e.printStackTrace(); #Z98D9Pv`o
} finally{ DUM,dFIlvF
try{ T{{J'
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if(ps!=null) { }i|o":-x+
ps.clearParameters(); D>VI{p
ps.close(); 2JUX29rER
ps=null; /vD5C
} #:DDx5%x<b
}catch(SQLException e){} .G?7t6A
DBUtils.closeConnection(conn); K:465r:
} m/cbRuPWgP
} \aU^c24>
public long getLast(){ K>,Kbs=D6
return lastExecuteTime; Y%anR|
} wvp\'* $
public void run(){ hc`9Y
long now = System.currentTimeMillis(); !|}J{
if ((now - lastExecuteTime) > executeSep) { W6E9
//System.out.print("lastExecuteTime:"+lastExecuteTime); k2j:s}RHY
//System.out.print(" now:"+now+"\n"); Gxy>aS3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); t \Fc <
lastExecuteTime=now; nxA]EFS
executeUpdate(); FOM~Uj
} PF1!aAvVb
else{ Kg~<h B6
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); aluXh?
} WFjNS'WI_
} j K$4G.x
} HI,1~Jw+
//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 |hiYV
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类写好了,下面是在JSP中如下调用。 pvDr&n9
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<% kIiId8l
CountBean cb=new CountBean(); JUF[Y^C
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \G#Qe*"'K
CountCache.add(cb); #-
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out.print(CountCache.list.size()+"<br>"); bqsb (C
CountControl c=new CountControl(); 7$8z}2
c.run(); ?*9U
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out.print(CountCache.list.size()+"<br>"); aVz<RS
%>