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: =e<;B_~.
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CountBean.java d~lB4
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/* % FN3/iM
* CountData.java YJioR4+q
* *""JE'wG
* Created on 2007年1月1日, 下午4:44 \M@9#bd
* CTqAhL 4}
* To change this template, choose Tools | Options and locate the template under pH#*:v!)
* the Source Creation and Management node. Right-click the template and choose Y+ZQN>
* Open. You can then make changes to the template in the Source Editor. p^=>N9
*/ W6kDQ&q
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package com.tot.count; ppwjr
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/** u9d4zR
* bo;;\>k
* @author CA0SH{PdW&
*/ J2c.J/o
public class CountBean { /U|>
private String countType; a{?`yO/ 2
int countId; mY}_9rTn|
/** Creates a new instance of CountData */ i0,'b61qE
public CountBean() {} lu]Z2xSv
public void setCountType(String countTypes){ ,34|_
this.countType=countTypes; 1pT
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} 6CK WKc
public void setCountId(int countIds){ H|E{n/g
this.countId=countIds; mPl2y3m%
} t#kPEiD
public String getCountType(){ i\4Q v"%
return countType; pHW
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} 5IK -V)
public int getCountId(){ uVO*@Kj+
return countId; 3$]SP1Mc(
} 1x\Vz\
} 3ug|H
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CountCache.java fxW,S
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/* r6B\yH2
* CountCache.java F4!,8)}
* ^uU'Qc4S=
* Created on 2007年1月1日, 下午5:01 {l /]+8G^
* A5d(L4Q]a(
* To change this template, choose Tools | Options and locate the template under /7EeM{,~
* the Source Creation and Management node. Right-click the template and choose 3YtFO;-
* Open. You can then make changes to the template in the Source Editor. ;n-)4b]\
*/ F vJJpPS
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package com.tot.count; f
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import java.util.*; q&eUw<(F
/** M<f=xY2$v
* "8pfLI
* @author 2TR l@
*/ &4aY5y`8+f
public class CountCache { FTB@70
public static LinkedList list=new LinkedList(); hq5=>p
/** Creates a new instance of CountCache */ pq
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public CountCache() {} /0w?"2-
public static void add(CountBean cb){ f z)i9D@
if(cb!=null){ Bld%d:i
list.add(cb); Jk$XL<t
} <Pg]V:=g'
} \ 2Jr(?U
} x]({Po4
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CountControl.java EYwDv4H,g
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/* 8vN} v3HV&
* CountThread.java fO!S^<9,-
* #3:;&@#
* Created on 2007年1月1日, 下午4:57 B{ i5UhxD
* W]8tp@
* To change this template, choose Tools | Options and locate the template under 9!XW):
* the Source Creation and Management node. Right-click the template and choose S-FoyID\H
* Open. You can then make changes to the template in the Source Editor. >[4;K&$B
*/ myp}DI(
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package com.tot.count; kg2?I L
import tot.db.DBUtils; ?}QHEk:H
import java.sql.*;
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/** bLx70$
* fk(l.A$
* @author OG#7Va
*/ #8N9@
public class CountControl{ 3@k;"pFa<
private static long lastExecuteTime=0;//上次更新时间 *fBI),bZa
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7e,EI9?.
/** Creates a new instance of CountThread */ =4RBHe8`
public CountControl() {} "HWl7c3q
public synchronized void executeUpdate(){ \wmNeGC2
Connection conn=null; %cM2;a=2
PreparedStatement ps=null; X@,xwsM%tb
try{ SE0"25\_G
conn = DBUtils.getConnection(); xg'FC/1LD
conn.setAutoCommit(false); T=8>0D^v5
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ulnG|3A9
for(int i=0;i<CountCache.list.size();i++){ RI#Cr+/
CountBean cb=(CountBean)CountCache.list.getFirst(); 4|+6a6
CountCache.list.removeFirst(); .x__X3P>\
ps.setInt(1, cb.getCountId()); l}>gG[q!
ps.executeUpdate();⑴ nwd
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//ps.addBatch();⑵ 1goK>=-^
} J~Gq#C^e
//int [] counts = ps.executeBatch();⑶ h[()!\vBy
conn.commit(); F, ^<
}catch(Exception e){ URW#nm?
e.printStackTrace(); &hmyfH&S
} finally{ c;,jb
try{ e+"rL]
if(ps!=null) { opz.kP[e,
ps.clearParameters(); H6<\7W89y
ps.close(); \ H#zRSbZ
ps=null; }r&^*"
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} q#v&&]N=
}catch(SQLException e){} Sd]` I)
DBUtils.closeConnection(conn); xUYUOyV
} Pnb?NVP!^9
} Y(WX`\M97
public long getLast(){ f1Ruaz-
return lastExecuteTime; cad%:%p
} NpRT\cx3
public void run(){ /easmf]
long now = System.currentTimeMillis(); xbex6i"ZE
if ((now - lastExecuteTime) > executeSep) { )j6VROt
//System.out.print("lastExecuteTime:"+lastExecuteTime); DU g
//System.out.print(" now:"+now+"\n"); ffGiNXCM
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }U$Yiv
lastExecuteTime=now; A_: Bz:
executeUpdate(); YQ>M&lnQ<
} E<>Ev_5 >
else{ 6:i(<7
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); #UH|,>W6
} Q!Rknj 2
} v&}mbt-
}
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//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 &Y"u*)bm
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类写好了,下面是在JSP中如下调用。 -#v1b>ScY
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<% >^%]F[Wo
CountBean cb=new CountBean(); %WrUu|xj>_
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <J=9,tv<
CountCache.add(cb); ,R=Mr}@u
out.print(CountCache.list.size()+"<br>"); C?Dztkz
CountControl c=new CountControl(); ~={8b
c.run(); VsOn j~@
out.print(CountCache.list.size()+"<br>"); R9gK> }>Y
%>