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: ~A2{$C
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CountBean.java +>h}Uz
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/* +?Vj}p;
* CountData.java q&OF?z7H
* u+%Ca,6
* Created on 2007年1月1日, 下午4:44 /~[+'
* $mOVo'2
* To change this template, choose Tools | Options and locate the template under 4^cDp!8
* the Source Creation and Management node. Right-click the template and choose g"aWt%
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* Open. You can then make changes to the template in the Source Editor. ^F2OTz4n
*/ $51M'Qu
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package com.tot.count; P1KXvc}JGe
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/** a,g3/
* s\i:;`l:=5
* @author |&OW_*l
*/ r8>(ayJ,
public class CountBean { BK`NPC$a
private String countType; ,(&jG^IpVJ
int countId;
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/** Creates a new instance of CountData */ IlQNo 1
public CountBean() {} ATx6YP@7~
public void setCountType(String countTypes){ mOgsO
this.countType=countTypes; &AM<H}>
} 7R9.g6j
public void setCountId(int countIds){ qNb|6/DG
this.countId=countIds; fd~a\5%e
} +@*}_%^l"
public String getCountType(){ P7ktr?V0a
return countType; 9D@
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} ML@-@BaN
public int getCountId(){ 0qP&hybL[(
return countId; rP$vZ^/c
} RO.GD$ 3n
} z\64Qpfm
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CountCache.java b{Srd3
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/* +6paM
* CountCache.java -+MGs]),
* v`&
* Created on 2007年1月1日, 下午5:01 qZw4"&,j$
* pkTg.70wU
* To change this template, choose Tools | Options and locate the template under GjTj..G/
* the Source Creation and Management node. Right-click the template and choose Pf,S`Uw;
* Open. You can then make changes to the template in the Source Editor. s&(,_34
*/ &%J+d"n(
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package com.tot.count; $p_FrN{
import java.util.*; [4qCW{x._
/** Xc)V;1
* %f??O|O3
* @author h M{&if
*/ ~{69&T}9
public class CountCache { ttQX3rmF01
public static LinkedList list=new LinkedList(); i>=d7'oR
/** Creates a new instance of CountCache */ "p]F q,
public CountCache() {} +!_?f'kv`
public static void add(CountBean cb){ 0u0<)gdX
if(cb!=null){ @L?X}'0xI4
list.add(cb); X3nt*G1dL
} Bfh[C]yy
} b-Fv
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} tF:'Y ~3 p
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CountControl.java -anLp8G*
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/* $xx5+A%,
* CountThread.java 38Rod]\E
* $7Sbz&)y3
* Created on 2007年1月1日, 下午4:57 si`{>e~`6P
* @q=l H
*=
* To change this template, choose Tools | Options and locate the template under JiFy.Pf
* the Source Creation and Management node. Right-click the template and choose W40GW
* Open. You can then make changes to the template in the Source Editor. {8L)Fw
*/ 31BN ?q
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package com.tot.count; HbQvu@
import tot.db.DBUtils; #Bo/1G=
import java.sql.*; lo }[o0X
/** @3D8TPH
* e[`E-br^
* @author @\~qXz{6J
*/ !AR$JUnX
public class CountControl{ 6Mpbmfr
private static long lastExecuteTime=0;//上次更新时间 r 5$(
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *~p~IX{
/** Creates a new instance of CountThread */ [w iI
public CountControl() {} y&y(<
public synchronized void executeUpdate(){ 5fh@nR
Connection conn=null; Z=;+)
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PreparedStatement ps=null; |.bp
try{ TmN}TMhZ
conn = DBUtils.getConnection(); IKJ~sw~AQ
conn.setAutoCommit(false); O5"o/Y~m
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); c[=%v]j:u
for(int i=0;i<CountCache.list.size();i++){ .aRL'1xHl
CountBean cb=(CountBean)CountCache.list.getFirst(); U3ygFW%
CountCache.list.removeFirst(); 3J\NkaSR
ps.setInt(1, cb.getCountId()); ^RN1?dXA
ps.executeUpdate();⑴ 7ko7)"N
//ps.addBatch();⑵ *%0f^~!G<p
} A<6V$e$:2
//int [] counts = ps.executeBatch();⑶ H>AzxhX[n
conn.commit(); kvU0$1
}catch(Exception e){ ?$O5w*
e.printStackTrace();
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} finally{ o]NL_SM_
try{ 3t(8uG<rL
if(ps!=null) { 0m5Q;|mH
ps.clearParameters(); -25#Vh
ps.close(); d6lhA 7
ps=null; !g? ~<`
} qZ!1>`B
}catch(SQLException e){} \!UNale
DBUtils.closeConnection(conn); S"|sD|xOb
} M/U$x /3K
} &}Y_EHj}
public long getLast(){ %iPu51+=
return lastExecuteTime; B3I\=
} ?Y"bt^4j
public void run(){ d}f| HOFq
long now = System.currentTimeMillis(); ~A8%[.({5
if ((now - lastExecuteTime) > executeSep) { ?KxI|os
//System.out.print("lastExecuteTime:"+lastExecuteTime); Rl 4r 9
//System.out.print(" now:"+now+"\n"); '-#6;_ i<
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >/"XX,3
lastExecuteTime=now; @4:cn
executeUpdate(); PN:8H>
} RJs_ S
else{ #( nheL
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); =J8)Z'Jr
} /,v:!*
} Q6S[sTKR
} M3Kpp_d_!
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 |Sg *j-.
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类写好了,下面是在JSP中如下调用。 FH8?W|
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<% Fm}O,=
CountBean cb=new CountBean();
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }wR)p
CountCache.add(cb); F *;
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out.print(CountCache.list.size()+"<br>"); +Z XGT
CountControl c=new CountControl(); hBsjO3n
c.run(); 2h&pm
out.print(CountCache.list.size()+"<br>"); ;J\{r$q
%>