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: [r3 !\HI7x
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CountBean.java #?5 (o
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/* CJ(NgYC h
* CountData.java k xP-,MD
* 7bqBk,`9
* Created on 2007年1月1日, 下午4:44 4 d;|sI@
* SLO%7%>p
* To change this template, choose Tools | Options and locate the template under I{
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* the Source Creation and Management node. Right-click the template and choose ^sa#8^,K
* Open. You can then make changes to the template in the Source Editor. Kpb#K[(]&
*/ M54j@_81pX
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package com.tot.count; g1XZ5P} f
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/** ipQLK{]t
* =Qh\D
* @author e:DkGy`-s
*/ Z&0'a
public class CountBean { 9U{a{~b
private String countType; Dpvk\t
int countId; 9v?N+Rb
/** Creates a new instance of CountData */ =.y~f A!
public CountBean() {} Em?d*z
public void setCountType(String countTypes){ ] x\-$~E
this.countType=countTypes; 8dV=[+
} >"gf3rioW
public void setCountId(int countIds){ Xua+cVc\y
this.countId=countIds; (EK"V';
} a-l;vDs
public String getCountType(){ KiI!frm1
return countType; K/A*<<r
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} |3F02
public int getCountId(){ gT$Ju88
return countId; M(jgd
} [PQ?#:r
} "J+3w
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CountCache.java dlJbI}-v=
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/* At flf2 K
* CountCache.java 8CnRi
* 8#(Q_
* Created on 2007年1月1日, 下午5:01 =:D aS`~V
* M%1}/!J3
* To change this template, choose Tools | Options and locate the template under H2Z1TIh
* the Source Creation and Management node. Right-click the template and choose M7+nW ; e%
* Open. You can then make changes to the template in the Source Editor. e_s&L,ze
*/ la( <8
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package com.tot.count; '3TW [!m
import java.util.*; h.-@ F
/** *GxTX3i}vc
* ]4h92\\965
* @author {Z3dF)>
*/ G2t;DN(
public class CountCache { .mDM[e@'
public static LinkedList list=new LinkedList(); SG-'R1
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/** Creates a new instance of CountCache */ `D`sr[3n
public CountCache() {} \"CZI<=TB
public static void add(CountBean cb){ *g y{]
if(cb!=null){ PUo/J~ v
list.add(cb); uHAT#\m:
}
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} dFH$l
} `)GrwfC
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CountControl.java e&>;*$)
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/* %Eb%V ($
* CountThread.java _<a7CCg
* ms!r ef4`+
* Created on 2007年1月1日, 下午4:57 D[_| *9BC
* q4}PM[K?=\
* To change this template, choose Tools | Options and locate the template under QmLF[\Oo_
* the Source Creation and Management node. Right-click the template and choose A,%C,*)Cg
* Open. You can then make changes to the template in the Source Editor. w3=%*<
*/ n) k1
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package com.tot.count; ,WJH}(h"D
import tot.db.DBUtils; uiJS8(Cb
import java.sql.*; ,0E{h}(
/** taFn![}/!g
* iC W*]U
* @author 4hAl-8~Q6
*/ Pu"R,a
public class CountControl{ :>TEDy~O%
private static long lastExecuteTime=0;//上次更新时间 )//I'V
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 PH>
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/** Creates a new instance of CountThread */ z I+\Oll#Q
public CountControl() {} td4[[ /
public synchronized void executeUpdate(){ =JKv:</.G
Connection conn=null; qTAc[Ko
PreparedStatement ps=null; V5GW:QT
try{ ~=KJzOS,S
conn = DBUtils.getConnection(); i&vaeP25)
conn.setAutoCommit(false); uu}x@T@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); A |3tI
for(int i=0;i<CountCache.list.size();i++){ #]#sGmW/L
CountBean cb=(CountBean)CountCache.list.getFirst(); m;D- u>o
CountCache.list.removeFirst(); G!Um,U/g
ps.setInt(1, cb.getCountId()); I! > \#K
ps.executeUpdate();⑴ [Z~ 2
//ps.addBatch();⑵ ukv tQz)
} e"'#\tSG
//int [] counts = ps.executeBatch();⑶ B Ce|is0
conn.commit(); K-f1{ 0
}catch(Exception e){ x5QaM.+=J
e.printStackTrace(); esHQoIhd
} finally{ ZR$'u%+g'
try{ ^)?d6nI
if(ps!=null) { &BtK($
ps.clearParameters(); )r[&RGz6
ps.close(); Rb%%?*|
ps=null; 5w\fSY
} C=s1R;"H
}catch(SQLException e){} k6Uc3O
DBUtils.closeConnection(conn); lj{VL}R
} ~}!3G
} zOV=9"~{
public long getLast(){ (u]N
return lastExecuteTime; Iw<j T|y)
} *dvDap|8W
public void run(){ %0$qP0|`3I
long now = System.currentTimeMillis(); M@3"<[g
if ((now - lastExecuteTime) > executeSep) { kN%MP6? J
//System.out.print("lastExecuteTime:"+lastExecuteTime); HLBkR>e
//System.out.print(" now:"+now+"\n"); *loOiM\5a
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); r}0\}~'?c
lastExecuteTime=now; iA0q_( \X
executeUpdate(); #U*_1P0h
} zNY)'
else{ 4;HJ;0-ps
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); R(-<BtM!-
} 5C"QE8R o
} ^/5XZ} *
} d/}SAvtt
//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 ATy*^sc&"
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类写好了,下面是在JSP中如下调用。 uZZU{U9h
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<% *=fr8
CountBean cb=new CountBean(); ;SwMu@tg
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); l~D N1z6`
CountCache.add(cb); U `o^mtW.
out.print(CountCache.list.size()+"<br>"); :QWq"cBem
CountControl c=new CountControl(); Hg9CZMko
c.run(); \}~s2Y5j
out.print(CountCache.list.size()+"<br>"); lc_E!"1
%>