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: NLu[<u U*
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CountBean.java .[+}nA,g%~
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/* tN.$4+
* CountData.java hiv {A9a?
* ^Vi{._r
* Created on 2007年1月1日, 下午4:44 \58bz<u"
* 9Vl}f^Gn
* To change this template, choose Tools | Options and locate the template under /N#=Tol
* the Source Creation and Management node. Right-click the template and choose rGrR;
* Open. You can then make changes to the template in the Source Editor. my/KsB
*/ abv*X1
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package com.tot.count; ?op;#/Q(
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/** eSHsE3}h
* <Mu T7x-
* @author =[zP
*/ `+0dz,
public class CountBean { e
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private String countType; | UB)q5I
int countId; ;kWWzg
/** Creates a new instance of CountData */ vvs2:87zvJ
public CountBean() {} +
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public void setCountType(String countTypes){ O hRf&5u$
this.countType=countTypes; [#YzU^^Ib
} @eDs)mY
public void setCountId(int countIds){ f96`n+>xi
this.countId=countIds; i8p$wf"aW
} m#R"~ >
public String getCountType(){ Qv
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return countType; |ICn/r~
} >&ZlCE
public int getCountId(){ `7'^y
return countId; 2h#.:!/SMw
} T1R~^x1
} ~]].i~EV(
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CountCache.java ]*g f$D
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/* +FAxqCkA
* CountCache.java X|/RV4x@Cq
* m9\"B3sr
* Created on 2007年1月1日, 下午5:01 :_]0 8
* ZJ~0o2xZ'
* To change this template, choose Tools | Options and locate the template under .z=%3p8+
* the Source Creation and Management node. Right-click the template and choose iBtG@M
* Open. You can then make changes to the template in the Source Editor. TvS<;0~K
*/ 4[&&E7]EX
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package com.tot.count; V#|/\-@
import java.util.*; 2b,edJVt?
/** dA E85
* 9[teG5wAa
* @author 23Dld+E&
*/ Nr+~3:3
public class CountCache { dG8mE&$g
public static LinkedList list=new LinkedList(); p~Cz6n
/** Creates a new instance of CountCache */ mXS"nd30bD
public CountCache() {} H "5,To
public static void add(CountBean cb){ >8x)\'w
if(cb!=null){ /R?[/`)f&
list.add(cb); .o5K X*
} VbMud]40F
} P-$ ,
} SS24@:"{
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CountControl.java KATf9-Sz
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/* ==gL!e{
* CountThread.java mdQe)>
* xpCZlOld
* Created on 2007年1月1日, 下午4:57 r[T(R9k
* Hz[1c4)'F
* To change this template, choose Tools | Options and locate the template under aMxj{*v7
* the Source Creation and Management node. Right-click the template and choose &j ;91wEn
* Open. You can then make changes to the template in the Source Editor. ssS"X@VZ
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*/ m+:JNgX6
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package com.tot.count; %`K{0b
import tot.db.DBUtils; HmkxE
import java.sql.*; x7G)^
/** 7=yjd)Iy9m
* w^^l,
* @author nd,\<}uP9
*/ Y<kz+d,C
public class CountControl{ W(Md0*
private static long lastExecuteTime=0;//上次更新时间 K'e,9P{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 u"%D;
/** Creates a new instance of CountThread */ t#8QyN
public CountControl() {} 8B-mZFXpK
public synchronized void executeUpdate(){ Q4*{+$A
Connection conn=null; 0UW_ Pbh6
PreparedStatement ps=null; 2xiE#l-V2
try{ 2<h~:
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conn = DBUtils.getConnection(); ;K|K]c
conn.setAutoCommit(false); f2pA+j5[
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^c/3!"wK
for(int i=0;i<CountCache.list.size();i++){ <gGO
CountBean cb=(CountBean)CountCache.list.getFirst(); b<#zgf
CountCache.list.removeFirst(); z C$F@
ps.setInt(1, cb.getCountId()); t9*e" QH
ps.executeUpdate();⑴ (3Xs
//ps.addBatch();⑵ [{R>'~
} 1*$6u5.=F
//int [] counts = ps.executeBatch();⑶ ZR0 OqSp]
conn.commit(); iR PE0
}catch(Exception e){ J %B/(v`
e.printStackTrace(); X[dH*PV
} finally{ yi Xb<g+B
try{ BFP@Yn~k
if(ps!=null) { %Ie,J5g5
ps.clearParameters(); ]q4LNo
ps.close(); ZREy I(_
ps=null; {Y=k`t,
} b{)kup
}catch(SQLException e){} qmGHuQVe
DBUtils.closeConnection(conn); AS:k&t
} f<$*,P
} ( xzruI5P
public long getLast(){ oOLA&N-A~
return lastExecuteTime; 5D?{dA:Rq
} 0bJT0_
public void run(){ $bF+J8%D
long now = System.currentTimeMillis(); CS*lk!C
if ((now - lastExecuteTime) > executeSep) { c yP+a
//System.out.print("lastExecuteTime:"+lastExecuteTime); d(d3@b4Ta
//System.out.print(" now:"+now+"\n"); #Tag"b`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zFipuG02
lastExecuteTime=now; \L$]2"/v-
executeUpdate(); fk6=;{
} 9!_LsQ\)
else{ UY,u-E"
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); bA$ElKT
} #lSGH 5Fp?
} 7h!nt=8Y
} [T)>RF
//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 9-&@Y
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类写好了,下面是在JSP中如下调用。 r8N)]HsZH
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<% 5 ';[|f
CountBean cb=new CountBean(); ;9fWxH
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); EV* |\ te
CountCache.add(cb); -iW>T5f
out.print(CountCache.list.size()+"<br>"); S;iD~> KP
CountControl c=new CountControl(); !B{(EL=g
c.run(); qC& xuu|
out.print(CountCache.list.size()+"<br>"); hBcklI
%>