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: 1 :$#a
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CountBean.java ^|p D(v
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/* y0(.6HI
* CountData.java EyVu-4L:#
* u"V,/1++\
* Created on 2007年1月1日, 下午4:44 k{#k:
* -,+C*|mu
* To change this template, choose Tools | Options and locate the template under 8 yi#] 5`Q
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. h)ZqZ'k$
*/ } % Ie
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package com.tot.count; K$,<<hl
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/** 1uN;JN
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* 0$c(<+D
* @author aT IzfqCM
*/ f~\H|E8(
public class CountBean { hBnUpYec
private String countType; |yO%w #
int countId; VnkhY
/** Creates a new instance of CountData */ (?8i^T?WP=
public CountBean() {} -.?
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public void setCountType(String countTypes){ 3%(r,AD
this.countType=countTypes; aWJ
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} zEO~mJzo
public void setCountId(int countIds){ q x1Js3%
this.countId=countIds; I*Dj@f`
} )#M$ov
public String getCountType(){ O&aD]~|
return countType; = FV12(U
} AQ(n?1LU
public int getCountId(){ %G2g
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return countId; Xw'sh#i2
} Q njK<}M9
} TO5y.M|7
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CountCache.java @OT$* Qh
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/* =dHdq D
* CountCache.java dtY8>klI
* qF$y
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* Created on 2007年1月1日, 下午5:01 D=z="p\
* BNjMq
* To change this template, choose Tools | Options and locate the template under \.i ejB
* the Source Creation and Management node. Right-click the template and choose NY<qoV
* Open. You can then make changes to the template in the Source Editor. s?m_zJh
*/ &F:.V$
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package com.tot.count; =J)-#|eZG
import java.util.*; Hpz1Iy@
/** %pOxt<
* Ig?9"{9p
* @author @<$m`^H
*/ (-0d@eqw
public class CountCache { X6Z/xb@
public static LinkedList list=new LinkedList(); `u_MdB}<x;
/** Creates a new instance of CountCache */ CfS;F
public CountCache() {} VhLfSN>W
public static void add(CountBean cb){ $v2t6wS,"
if(cb!=null){ LqI&1$#
list.add(cb);
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} 1>\V>g9
} q>K3a1x
} ?o6#i 3k#'
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CountControl.java A7#nBHwxZ
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/* /%7&De6Xg
* CountThread.java o[eZ"}~
* 9^H.[t
* Created on 2007年1月1日, 下午4:57 Tr}XG
* ep},~tPZn
* To change this template, choose Tools | Options and locate the template under V8WSJ=-&
* the Source Creation and Management node. Right-click the template and choose B0Z>di:
* Open. You can then make changes to the template in the Source Editor. wE<r'
*/ [+W<;iep
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package com.tot.count; N}#"o
import tot.db.DBUtils; icIWv
import java.sql.*; +3XaAk
/** *fj]L?,
* 60ciI,_`
* @author A\9LJ#E
*/ Q;z!]hjBM
public class CountControl{ RS&BS;
private static long lastExecuteTime=0;//上次更新时间 - e0[$v
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Ylu\]pr9|C
/** Creates a new instance of CountThread */ 8BZ&-j{
public CountControl() {} <2<2[F5Q%
public synchronized void executeUpdate(){ T+RC#&>
Connection conn=null; !fe_w5S^
PreparedStatement ps=null; @^ &p$:
try{ Z;1r=p#s
conn = DBUtils.getConnection(); H0])>1sWB
conn.setAutoCommit(false); 9Qu(RbDqC
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =<PEvIn
for(int i=0;i<CountCache.list.size();i++){ ':tdb$h
CountBean cb=(CountBean)CountCache.list.getFirst(); s~>1TxJe
CountCache.list.removeFirst(); aqK+ u.H
ps.setInt(1, cb.getCountId()); #UwX~
ps.executeUpdate();⑴ 8Ed axeDq
//ps.addBatch();⑵ .=-a1p/
} [lSQMoi3
//int [] counts = ps.executeBatch();⑶ O
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conn.commit(); Sa@'?ApH
}catch(Exception e){ L[nDjQn"
e.printStackTrace(); {' 0#<Z
} finally{ 7 p!ROl^
try{ `J03t\
if(ps!=null) { H
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ps.clearParameters(); ?tqJkL#
ps.close(); YjL'GmL<
ps=null; za 7+xF
} @'M"c
q
}catch(SQLException e){} !J@!2S9
DBUtils.closeConnection(conn); dXM8iP
} 1$C?+H
} [kxOv7a
public long getLast(){ .Oc j|A6
return lastExecuteTime; PXtF#,roP
} 3XDU(#
public void run(){ }hg2}g99
long now = System.currentTimeMillis(); W4k$m2
if ((now - lastExecuteTime) > executeSep) { s>\^dtG7
//System.out.print("lastExecuteTime:"+lastExecuteTime); GBpdj}2=
//System.out.print(" now:"+now+"\n"); n=$ne2/
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); .<fdX()e,
lastExecuteTime=now; Q}<QE:-&E
executeUpdate(); yVGf[~X
} @Y.r ,q
else{ FAM:; F30
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); o^"OKHU,S0
} ;;Z'd@
} &&LB0vH!J
} ir{
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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 H7Z`a QC
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类写好了,下面是在JSP中如下调用。 /#@tv~Z^
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<% HRM-r~2:-]
CountBean cb=new CountBean(); -gt?5H h
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); oyk&]'>
CountCache.add(cb); .b<W*4{j0H
out.print(CountCache.list.size()+"<br>"); :wg=H
CountControl c=new CountControl(); 0#uB[N
c.run(); Qhc;Zl
out.print(CountCache.list.size()+"<br>"); J#i7'9g
%>