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: B=^2g}mgK
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CountBean.java %Ln?dF+
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/* ^$6bs64FSm
* CountData.java
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* #d$d&W~gE
* Created on 2007年1月1日, 下午4:44 <vO8_2,V-
* <w%DyRFw3
* To change this template, choose Tools | Options and locate the template under c|3h|
* the Source Creation and Management node. Right-click the template and choose Dt
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* Open. You can then make changes to the template in the Source Editor. jCam,$oE
*/ 5Bzuj`
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package com.tot.count; kKNk2!z`M
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/** ` 3vN R"
* e(4bx5<*
* @author hE9'F(87a
*/ b^@`uDb6
public class CountBean { m|(I} |kT3
private String countType; vl>_e
int countId; B44]NsYks~
/** Creates a new instance of CountData */ m]
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public CountBean() {} R,fMZHAG
public void setCountType(String countTypes){ 01UqDdoj
this.countType=countTypes; ysQEJm^|-u
} 8UjCX[v
public void setCountId(int countIds){ t
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this.countId=countIds; xu0;a
} Y+}OClS
public String getCountType(){ !#l0@3
return countType; XtnIK
} K7n;Zb:BR
public int getCountId(){ }D8~^
return countId; q\-xg*'
} WX+< 4j
} FA<Z37:
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CountCache.java |F8;+nAVF#
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/* ~Q3WBOjn
* CountCache.java }6yxt9
* q{jk.:;'
* Created on 2007年1月1日, 下午5:01
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* :XNK-A W
* To change this template, choose Tools | Options and locate the template under 4'd;'SvF
* the Source Creation and Management node. Right-click the template and choose }A)^XZ/
* Open. You can then make changes to the template in the Source Editor. +5N^TnBtBL
*/ KzxW?Ji$S
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package com.tot.count; ZA 99vO
import java.util.*; oX%PsS
/** <VauJB*R
* #S/pYP`7
* @author ft*G*.0kO
*/ >'BU*
public class CountCache { sPZV>Q:zY
public static LinkedList list=new LinkedList(); IIYX|;1}X
/** Creates a new instance of CountCache */ nvm1.}=Cnd
public CountCache() {} ZlwcwoPib
public static void add(CountBean cb){ vr8J*36{
if(cb!=null){ ,3g]=f
list.add(cb); q(w1VcLZ
} q[Sp|C6x
} Q{(,/}kA-
} '_Hb}'sFI
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CountControl.java ORFr7a'K
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/* f@,hO5h(_|
* CountThread.java >TH-Q[
* c +"O\j'
* Created on 2007年1月1日, 下午4:57 Ply2DQr
* #b<lt'gC
* To change this template, choose Tools | Options and locate the template under T-<> )N5y
* the Source Creation and Management node. Right-click the template and choose uv_P{%TK
* Open. You can then make changes to the template in the Source Editor. ;mM\,
{Z
*/ 6+{ nw}e8
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package com.tot.count; #lLn='4
import tot.db.DBUtils; 4Tbi%vF{
import java.sql.*; q=j/s4~
/** @et3}-c
* -jklH/gF\%
* @author ^OGH5@"
*/ ocDVCCkxg
public class CountControl{ ! X#3w-K
private static long lastExecuteTime=0;//上次更新时间 PgGrk5;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 e!L sc3@
/** Creates a new instance of CountThread */ )PLc+J.I
public CountControl() {} l[x`*+ON:2
public synchronized void executeUpdate(){ 1^Y:XJ73
Connection conn=null; ,vHX>)M|
PreparedStatement ps=null; %\s#e
try{ 3n=O8Fp
conn = DBUtils.getConnection(); d}^:E
conn.setAutoCommit(false); *N&^bF"SF
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 7lBQd (
for(int i=0;i<CountCache.list.size();i++){ F#3$p$;B$
CountBean cb=(CountBean)CountCache.list.getFirst(); r4z}yt+
CountCache.list.removeFirst(); gE]a*TOZk
ps.setInt(1, cb.getCountId()); XV0<pV>
ps.executeUpdate();⑴ &*?!*+!,i
//ps.addBatch();⑵ ` wsMybe#
} n"Z,-./m
//int [] counts = ps.executeBatch();⑶ ?\/dfK:!
conn.commit(); [{d[f|
}catch(Exception e){ njx\$,ruN
e.printStackTrace(); O#89M%
} finally{ p-i]l.mT5
try{ rg]A_(3Bb
if(ps!=null) { II f >z_m
ps.clearParameters(); ZLFdnC@
ps.close(); >GF(.:7
ps=null; Dv\:b*
} ^FpiQF
}catch(SQLException e){} =[CS2VQ'
DBUtils.closeConnection(conn); hH@o|!y
} Y9c9/_CSj
} l{7Dv1[Ss
public long getLast(){ u/c~PxC
return lastExecuteTime; p|O-I&Xd
} !h~#L"z
public void run(){ SBB
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long now = System.currentTimeMillis(); 2l}FgD
if ((now - lastExecuteTime) > executeSep) { tg%WVy2
//System.out.print("lastExecuteTime:"+lastExecuteTime); 5eZg+ O
//System.out.print(" now:"+now+"\n"); +'6ea+$
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); dpOL1rrE
lastExecuteTime=now; ~d<`L[
executeUpdate(); iLQt9Hyk
} HS7
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else{ C
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); gT\y&
} {/VL\AW5$
} jwE(]u
} eNk!pI7g
//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 `[HoxCV3o
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类写好了,下面是在JSP中如下调用。 +^3L~?
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<% Gpp}Jpj
CountBean cb=new CountBean(); 22(]x}`
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ~a0}
CountCache.add(cb); d'@H@
out.print(CountCache.list.size()+"<br>"); #(wzl
CountControl c=new CountControl(); #Ew
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c.run(); ?+JxQlVDt-
out.print(CountCache.list.size()+"<br>"); EO!cv,[a
%>