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: 3WPMS/
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CountBean.java <6dD{{J]>p
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/* !!2~lG<]
* CountData.java `*}#Bks!
* oVl:./(IB
* Created on 2007年1月1日, 下午4:44 jf/;`br
* OMKEn!Wq
* To change this template, choose Tools | Options and locate the template under WgE~H)_%
* the Source Creation and Management node. Right-click the template and choose ]lz,?izMR
* Open. You can then make changes to the template in the Source Editor. EHzU`('?[
*/ JFYeOmR+l
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package com.tot.count; s4~c>voQB
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/** 3XL0Pm
* R0. `2=
* @author %NeKDE
*/ .WyI.Y1
public class CountBean { y;<jE.7>
private String countType; >IoOCQQ*
int countId; ,0-
/** Creates a new instance of CountData */
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public CountBean() {} q".l:T%|C}
public void setCountType(String countTypes){ lV]l`$XI
this.countType=countTypes; F>^k<E?,C
} 1ed#nB%
public void setCountId(int countIds){ dR$P-V\y`%
this.countId=countIds; oWXvkDN
} WqYl=%x"{V
public String getCountType(){ .Z/"L@
return countType; D;Az>]>q
} $Q47>/CUc^
public int getCountId(){ 6 _73
return countId; vKaX,)P;?
} ^~(bm$4r
} -$e\m]
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CountCache.java :U r%.0
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/* {?5EOp~
* CountCache.java Ma{|+\Q.Z
* dX+DE(y
* Created on 2007年1月1日, 下午5:01 q=96Ci _a
* OsC1('4@
* To change this template, choose Tools | Options and locate the template under _k
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* the Source Creation and Management node. Right-click the template and choose 4AP<mo
* Open. You can then make changes to the template in the Source Editor. C
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*/ c&'T By
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package com.tot.count; g00XZ0@
import java.util.*; ^[qmELW#7
/** )ZiJl5l@
* z`
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* @author a<vCAFQ
*/ Gia_B6*Y[
public class CountCache { Qz/=+A/4
public static LinkedList list=new LinkedList(); ;PLby]=O
/** Creates a new instance of CountCache */ bLf }U9
public CountCache() {} ~G"6^C:x
public static void add(CountBean cb){ @$~%C) %u
if(cb!=null){ hg\$>W~2
list.add(cb); BJ{mX>I(
} _jnH!Mw
} @-u/('vpB
} ,T1t`
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CountControl.java V1"+4&R^T_
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/* DmD*,[rD
* CountThread.java wAy;ZNu
* vH7"tz&RIp
* Created on 2007年1月1日, 下午4:57 srC'!I=s>8
* jQ7RH/?_
* To change this template, choose Tools | Options and locate the template under 'VO^H68
* the Source Creation and Management node. Right-click the template and choose %JiA,
* Open. You can then make changes to the template in the Source Editor. mtJI#P
*/ [nflQW6
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package com.tot.count; ~W`upx)j
import tot.db.DBUtils; xJZbax[
import java.sql.*; yQCfn1a)
/** (obeEH5J
* BIX%Bu0'f
* @author =u73AM}
*/ >F@7}Y(
public class CountControl{ 7?cZ9^z`w
private static long lastExecuteTime=0;//上次更新时间 a"hlPJlG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 G~^Pkl3%T
/** Creates a new instance of CountThread */ V&NOp
public CountControl() {} z!t&zkAK
public synchronized void executeUpdate(){ Z&/;6[
Connection conn=null; 6C) G
PreparedStatement ps=null; O7q-MeMM
try{ Az"3f
conn = DBUtils.getConnection(); HiVF<tN
conn.setAutoCommit(false); 9I9J}&4
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ggX'`bK
for(int i=0;i<CountCache.list.size();i++){ uKtrG,/ p
CountBean cb=(CountBean)CountCache.list.getFirst(); .qF@
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CountCache.list.removeFirst(); WvNX%se]3
ps.setInt(1, cb.getCountId()); ;xwa,1]
ps.executeUpdate();⑴ e
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//ps.addBatch();⑵ zneK)C8&q3
} J;'?(xO3\
//int [] counts = ps.executeBatch();⑶ }^P( p?~
conn.commit(); H}JH339
}catch(Exception e){ ILTd*f
e.printStackTrace(); t~X wF(";
} finally{ U3%!#E{
try{ TZPWMCN4
if(ps!=null) { C6O1ype
ps.clearParameters(); lXL\e(ow
ps.close(); $5cLhi"`
ps=null; S 8h/AW6l
} hGD7/qTN
}catch(SQLException e){} Lj({
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DBUtils.closeConnection(conn); Bn47O~
} S1 %{/w
} jcFh2
public long getLast(){ .|KxQn}
return lastExecuteTime; CI$F#j
} A^%z;( 0p
public void run(){ <k}>eGn
long now = System.currentTimeMillis(); T"8>6a@}E
if ((now - lastExecuteTime) > executeSep) {
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//System.out.print("lastExecuteTime:"+lastExecuteTime); (/Z~0hA[Q
//System.out.print(" now:"+now+"\n"); "t`r_Aw
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 18V*Cu
lastExecuteTime=now; H>-,1/IY
executeUpdate(); #j iQa"
} S
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else{ EmG`ga)s
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ANn{*h
} Lm:O
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} BxO2w1G
} 2%1g%
//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 F)5QpDmqb
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类写好了,下面是在JSP中如下调用。 Z(*nZT,
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<% )Qb1$%r.
CountBean cb=new CountBean(); Pw
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +5?sYp\
CountCache.add(cb); RAXqRP,iw
out.print(CountCache.list.size()+"<br>"); =EsKFt"
CountControl c=new CountControl(); SX/yY
c.run(); H,KU!1p
out.print(CountCache.list.size()+"<br>"); $//18+T
%>