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: =m7H)z)i*J
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CountBean.java MRfb[p3Cx
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/* 0VN7/=n|
* CountData.java zB*euHIqZ
* L@RIZu>ZW+
* Created on 2007年1月1日, 下午4:44 hN
* -v]Qhf&>
* To change this template, choose Tools | Options and locate the template under y,E.SB
* the Source Creation and Management node. Right-click the template and choose s)zJT
* Open. You can then make changes to the template in the Source Editor. u%u&F^y
*/ 1<.5ub*i4
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package com.tot.count; $ rUSKm#
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/** prtK:eGe2
* tdep|sD
* @author x)SralWb
*/ m:uPEpcU
public class CountBean { yto[8;)_
private String countType; [:h5}
int countId; F; 8*H1
/** Creates a new instance of CountData */ `
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public CountBean() {} Xc*U+M>U
public void setCountType(String countTypes){ mT@nn,
this.countType=countTypes; d "E^SBO&
} 0*8TS7.3
public void setCountId(int countIds){ 4zjs!AK%
this.countId=countIds; ba3*]01Yb
} LY 0]l$
public String getCountType(){ ,\YAnKn6_
return countType; P(,?#+]-
} w##^}nHOR
public int getCountId(){ Qd]we$G
return countId;
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} :ofBzTNwZ
} J0Z7l
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CountCache.java _c`K+o"3
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/* %Jp|z? [/
* CountCache.java vDFGd-S
* _{4^|{>Pv
* Created on 2007年1月1日, 下午5:01 e(?]SU|
* =2Cj,[$
* To change this template, choose Tools | Options and locate the template under wM~H(=s`D
* the Source Creation and Management node. Right-click the template and choose +1rkq\{l
* Open. You can then make changes to the template in the Source Editor. 7b[wu~'(
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*/ GIyF81KR 3
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package com.tot.count; \?**2{9&)
import java.util.*; 7f3O
/** o`n$b(VZ
* .iG&Lw\,
* @author kV;fD$iW;
*/ 7fHc[,
public class CountCache { .uF[C{RnO
public static LinkedList list=new LinkedList(); nXy>7H[0
/** Creates a new instance of CountCache */ Q >Qibr
public CountCache() {} g%nl!dgS
public static void add(CountBean cb){ h6~$/`&]b
if(cb!=null){ _n;;][]S
list.add(cb); OsqNB'X
} ]QVNn?PA8
} &V7M}@
} pO7Zs
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CountControl.java 9QQyl\
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/* x3 >
* CountThread.java nKoiG*PI
* |~!U4D\
* Created on 2007年1月1日, 下午4:57 t] aea*B
* -=`#fDvBn
* To change this template, choose Tools | Options and locate the template under 0@I S
* the Source Creation and Management node. Right-click the template and choose F@ Swe
* Open. You can then make changes to the template in the Source Editor. ,<-G<${
*/ 6$\jAd|
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package com.tot.count; ?W>qUrZ
import tot.db.DBUtils; qpIC{'A.
import java.sql.*; lVOu)q@l7g
/** x'<K\qp{{
* F$BbYf2i
* @author */:uV
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*/ `d7n?|pD
public class CountControl{ Zf$Np50@(
private static long lastExecuteTime=0;//上次更新时间 $5x ,6[&
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ryB}b1`D
/** Creates a new instance of CountThread */ '2^7-3_1
public CountControl() {} 5"XC$?I<}
public synchronized void executeUpdate(){ jhu 07HX_
Connection conn=null; NIdZ
PreparedStatement ps=null; ^9Qy/Er'
try{ =X\^J
conn = DBUtils.getConnection(); >/[GTqi
conn.setAutoCommit(false); eET&pP3Rp
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); AIMSX]m
for(int i=0;i<CountCache.list.size();i++){ a=cvCf
CountBean cb=(CountBean)CountCache.list.getFirst(); Ar*^;/
CountCache.list.removeFirst(); jTO),
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ps.setInt(1, cb.getCountId()); @,Gxk
ps.executeUpdate();⑴ hj'(*ND7z
//ps.addBatch();⑵ ktIi$v
} 2 3OC2|
//int [] counts = ps.executeBatch();⑶ 7X@mSXis
conn.commit(); o1M$.*
}catch(Exception e){ n3AaZp[
e.printStackTrace(); (hiyNMC
} finally{ <sK4#!K
try{ 8YC_3Yi%
if(ps!=null) { YIw1
ps.clearParameters(); ~ab:/!Z
ps.close(); .X# `k
ps=null; ^[:p|U2mA
} 1-lu\"H`
}catch(SQLException e){} nRyU]=-X
DBUtils.closeConnection(conn); i&{DOI%w
} M5gWD==uP
} -f*P
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public long getLast(){ 7}M2bH} \K
return lastExecuteTime; PDs@?nz,
} $Y69@s %f
public void run(){ 1UPC e
long now = System.currentTimeMillis(); '>r7V
if ((now - lastExecuteTime) > executeSep) { Ym3\pRFiD
//System.out.print("lastExecuteTime:"+lastExecuteTime); 'Ut7{rZ5
//System.out.print(" now:"+now+"\n"); hjZKUMG(k
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6DH~dL_",%
lastExecuteTime=now; "g$IP9?U
executeUpdate(); ^#-nE7
} DI+fwXeg
else{ x)( |[
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ep)>X@t
} _/i4MtM
} n2iJ%_zp
} +v=C@2T
//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 .l.a(_R
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类写好了,下面是在JSP中如下调用。 ~l)-wNqR4r
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<% YW7b)uYf
CountBean cb=new CountBean(); >0"+4<72
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :j+ ZI3@
CountCache.add(cb); @`gk|W3
out.print(CountCache.list.size()+"<br>"); h5(4*$%
CountControl c=new CountControl(); |`.([2
c.run(); B)0i:"q
out.print(CountCache.list.size()+"<br>"); {{QELfH2
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