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:
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CountBean.java t{UVX%b
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/* ^+-QY\N
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* CountData.java {
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* SN)Czi#7
* Created on 2007年1月1日, 下午4:44 Lea4-Gc
* `'|6b5`2j
* To change this template, choose Tools | Options and locate the template under W/A@q o"
* the Source Creation and Management node. Right-click the template and choose Pg.JI:>2Ku
* Open. You can then make changes to the template in the Source Editor. <mP_K^9c
*/ q5Zu'-Cx@
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package com.tot.count; H,<CR9@(5d
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/** (]sm9PO
* K?M~x&Q
* @author 8oUR/___
*/ `hY%HzV=
public class CountBean { b&A/S$*
private String countType; ?r=`Kl
int countId; /T
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/** Creates a new instance of CountData */ B t3++ Mj
public CountBean() {} 8~qpOQX^V
public void setCountType(String countTypes){ [Y@}{[q5
this.countType=countTypes; Xgh%2;:
} [jNVk3
public void setCountId(int countIds){ Uf_mwEE
this.countId=countIds; %;]/Z%!
} Y,mo}X<>
public String getCountType(){ sAO/yG
return countType; \8*j"@ !H
} A"DGn
public int getCountId(){ orWF>o=1
return countId; "=%YyH~WY
} {|%^'lS
} zZ9Ei-Q
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CountCache.java Gn6\n'r0
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/* e7iQG@i7
* CountCache.java MS2/<LD3d
* U4a8z<l$
* Created on 2007年1月1日, 下午5:01 }|-8-;
* Pvv7|AV
* To change this template, choose Tools | Options and locate the template under %26HB
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* the Source Creation and Management node. Right-click the template and choose \4G9fR4
* Open. You can then make changes to the template in the Source Editor. U1yspHiZ
*/ \2f?)id~
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package com.tot.count; -'oxenu
import java.util.*; ]We0 RD"+
/** m-[xrVV
* u,@ac[!vP
* @author Pr1OQbg]8
*/ BD.l 5~:
public class CountCache { f/kYm\Zc
public static LinkedList list=new LinkedList(); 4
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/** Creates a new instance of CountCache */ *!NW!,R
public CountCache() {} _=[pW2p
public static void add(CountBean cb){ lS2`#l >
if(cb!=null){ Vw.4;Zy(
list.add(cb); E-9>lb
} <X5V]f
} frQ=BV5%6
} Zic:d-Q47
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CountControl.java k9y/.Mu
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/* VzM (u_)
* CountThread.java 8M['-
* vXSpn71Jb
* Created on 2007年1月1日, 下午4:57 '7]9q#{su
* v49i.c9
* To change this template, choose Tools | Options and locate the template under $reQdN=~
* the Source Creation and Management node. Right-click the template and choose zs-,Y@ZL
* Open. You can then make changes to the template in the Source Editor. hz2f7g
*/ dKPx3Y'
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package com.tot.count; Nc(A5*
import tot.db.DBUtils; gF M~M(
import java.sql.*; 'Te'wh=Y
/** h5; +5B}D
* H M\}C.u
* @author U`4t4CHA
*/ :y!{=[>M(
public class CountControl{ 4Gh%PUV#
private static long lastExecuteTime=0;//上次更新时间 y$|OE%S
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Kku@!lv
/** Creates a new instance of CountThread */ ZN;fDv
public CountControl() {} BLo=@C%w5
public synchronized void executeUpdate(){ aXD|XE%
Connection conn=null; 7YU}-gi
PreparedStatement ps=null;
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try{ ][T>052v
conn = DBUtils.getConnection(); l'\m'Ioh
conn.setAutoCommit(false); Or()AzwE@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); gn${@y?
for(int i=0;i<CountCache.list.size();i++){ qEPC]es|T
CountBean cb=(CountBean)CountCache.list.getFirst(); T
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CountCache.list.removeFirst(); )9rJ]D^B
ps.setInt(1, cb.getCountId()); PkdL] !:
ps.executeUpdate();⑴ sTYA
//ps.addBatch();⑵ VSm{]Z!x
} rge/qUr/^
//int [] counts = ps.executeBatch();⑶ K~\Ocl
conn.commit(); Z
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}catch(Exception e){ %y\
e.printStackTrace(); @yn1#E,
} finally{ v1s0kdR,>
try{ 6.QzT(
if(ps!=null) { Ivc/g,
ps.clearParameters(); RMxFo\TK;
ps.close(); <a%RKjQvT
ps=null; y gTc
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} (,
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}catch(SQLException e){} -xU4s
DBUtils.closeConnection(conn); E$E#c8I:
} hdH}4W
} ;XGO@*V5T
public long getLast(){ *Ag,/Cm]
return lastExecuteTime; agPTY{;
} V3>JZH`
public void run(){ >iI-Cs7TD
long now = System.currentTimeMillis(); &\M<>>IB
if ((now - lastExecuteTime) > executeSep) { +T]D\];D
//System.out.print("lastExecuteTime:"+lastExecuteTime); &BJ"T
//System.out.print(" now:"+now+"\n"); @L5s.]vg=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); |]x>|Z?/u
lastExecuteTime=now; \zyvu7YA
executeUpdate(); 3g5
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} 3 etW4
else{ !"QvV6Lq\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); uBfSS\SX|
} ps3jw*QZ{5
} E4N{;'
} 5Z*6,P0
//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 @PyZ u7'
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类写好了,下面是在JSP中如下调用。 9._owKj
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<% xh9Os <
CountBean cb=new CountBean(); (od9adSehV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); xv>]e <":
CountCache.add(cb); MI\35~JAN
out.print(CountCache.list.size()+"<br>"); 6k*,Yei
CountControl c=new CountControl(); gano>W0
c.run(); ^K'@W
out.print(CountCache.list.size()+"<br>"); U/9_:
%>