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: ^hiY6N &
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CountBean.java xy]O8>b
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/* h AAh
* CountData.java *qm|A{FQR
* gDVsi
* Created on 2007年1月1日, 下午4:44 .@E5dw5
* DPjs?M<
* To change this template, choose Tools | Options and locate the template under Lo%vG{yTr
* the Source Creation and Management node. Right-click the template and choose {KNaJ/:>W
* Open. You can then make changes to the template in the Source Editor. \^*:1=|7u]
*/ $j.;$~F
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package com.tot.count; tkT,M,]?9
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/** vt{[_L(h
* r=5S0
* @author !i) !|9e
*/ v?OVhV
public class CountBean { lG\uJxV
private String countType; D,}bTwRb-
int countId; =S`h/fru
/** Creates a new instance of CountData */ D{6y^@/
public CountBean() {} ?"mZb#%
public void setCountType(String countTypes){ K2zln_W
this.countType=countTypes; ywAvqT,
} dGYR
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public void setCountId(int countIds){ (vO3vCYeQ
this.countId=countIds; .oyAi||
} T0tX%_6`
public String getCountType(){ Y2x|6{ #
return countType; Gu*y7I8
} 1`K-f
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public int getCountId(){ Q;$k?G=l
return countId; xrPZy*Y,
} Xx{| [2`
} VGc*aQYa
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CountCache.java o>r
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/*
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* CountCache.java *'-4%7C`1
* ?.SGn[
* Created on 2007年1月1日, 下午5:01 b!]O]dk#
* (p[#[CI9
* To change this template, choose Tools | Options and locate the template under +d6onO{8
* the Source Creation and Management node. Right-click the template and choose v1,#7sAW'
* Open. You can then make changes to the template in the Source Editor. N.JR($N$
*/ ?>h
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package com.tot.count; '#f<wfn
import java.util.*; Iw`tbN
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/** .D
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* @KTuG ?.
* @author <R]m(
*/ {s
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public class CountCache { ojy^A
public static LinkedList list=new LinkedList(); i wgt\ux.
/** Creates a new instance of CountCache */ e,xL~P{|
public CountCache() {} FMVAXOO
public static void add(CountBean cb){ lV$JCNe
if(cb!=null){ LS[o7 !T(
list.add(cb); B-MS@<2
} ,a{85HLr]
} rkjnw@x\
} 5G`HJ6
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CountControl.java [A7TSN
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/* mH$tG
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* CountThread.java 3J#LxYK
* ty,oj33
* Created on 2007年1月1日, 下午4:57 KV_/fa~Ry
* =~+ WJN
* To change this template, choose Tools | Options and locate the template under =xo0T 6
* the Source Creation and Management node. Right-click the template and choose o pTXI*QA
* Open. You can then make changes to the template in the Source Editor. ,W}:vdC
*/ ( V4Ppg
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package com.tot.count; eA4D.7HDK
import tot.db.DBUtils; ,m=G9QcN
import java.sql.*; j;3I` :
/** )q=F_:$
* _eKO:Y[e
* @author m.K cTM%j
*/ 9r? Z'~,Za
public class CountControl{ )dkU4]
private static long lastExecuteTime=0;//上次更新时间 VmqJMU>.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 +l7)7qKx
/** Creates a new instance of CountThread */ l(Rn=?
public CountControl() {} uyWheR
public synchronized void executeUpdate(){ b(0<,r8
Connection conn=null; .$&^yp
PreparedStatement ps=null; G,)zn9X
try{ ai_ve[A
conn = DBUtils.getConnection(); o]<Z3)
conn.setAutoCommit(false); XRV]u|w=g
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 3ay},3MCV%
for(int i=0;i<CountCache.list.size();i++){ ?@rd,:'dE
CountBean cb=(CountBean)CountCache.list.getFirst(); i(j/C
CountCache.list.removeFirst(); ]{1{XIF
ps.setInt(1, cb.getCountId()); v$]B;;[A
ps.executeUpdate();⑴ f7x2"&?vg
//ps.addBatch();⑵ 'zI(OnIS
} B]X8KzLu
//int [] counts = ps.executeBatch();⑶ "#~>q(4^
conn.commit(); w5%Yi{
}catch(Exception e){ z5jw\jBD
e.printStackTrace(); TPN+jK
} finally{ bXs=<`>
try{ $%~JG(
if(ps!=null) { }^&S^N7
ps.clearParameters(); ~&<#H+O
ps.close(); 4CM'I~
ps=null; RCWmdR#}V
}
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}catch(SQLException e){} >jI.$%L$
DBUtils.closeConnection(conn); 4qid+ [B
} Wlc&QOfF
} <w9~T TS
public long getLast(){ cXb*d|-|N
return lastExecuteTime; o!tC{"g
} w)EYj+L
public void run(){ +u$l]~St\
long now = System.currentTimeMillis(); #LasTN9
if ((now - lastExecuteTime) > executeSep) { q/ljH_-
//System.out.print("lastExecuteTime:"+lastExecuteTime); -ZaeX]^&Q\
//System.out.print(" now:"+now+"\n"); @ZJL]TO
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); pl]|yIZ
lastExecuteTime=now; KqFI2@v
executeUpdate(); i=gZ8Q=H
} BP3Ha8/X
else{ 1wR[nBg*|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); o Xm
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} QHNyH
} ~[%CUc"
} )]P(!hW.
//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 :F:1(FDP
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类写好了,下面是在JSP中如下调用。 *z~,|DQ(A
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<% \BnU?z
CountBean cb=new CountBean(); F rckA
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); & P-8_I
CountCache.add(cb); *JJ8\R&P0
out.print(CountCache.list.size()+"<br>"); jYp!?%!
CountControl c=new CountControl(); Jq/itsg
c.run(); {+67<&g
out.print(CountCache.list.size()+"<br>"); ~IhM(Q*mO!
%>