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: o/p'eY:)
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CountBean.java Z.mnD+{
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/* <>K@#|%Y&
* CountData.java ^<nN~@j
* !d=Q@oy5
* Created on 2007年1月1日, 下午4:44 'gv7&$X}4
* OvW/{
* To change this template, choose Tools | Options and locate the template under !Mk:rO-L
* the Source Creation and Management node. Right-click the template and choose ,__|SnA.
* Open. You can then make changes to the template in the Source Editor. s`"ALn8m
*/ be5NasC
# fl%~Y
package com.tot.count; h}$]3/5H
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/** m#(ve1E
* /pDI
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* @author 1~ZKpvu
*/ 0B[eG49
public class CountBean { sTGe=}T8
private String countType; /yj-^u\R
int countId;
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/** Creates a new instance of CountData */ !;YQQ<D
public CountBean() {} 2\=cv
public void setCountType(String countTypes){ -Fs^^={Q
this.countType=countTypes; 9wC:8@`6E
} O5p]E7/e
public void setCountId(int countIds){ \ |9KOulr
this.countId=countIds; Zx}.mt#}8
} [/I1%6;
public String getCountType(){ vH^^QI:em
return countType; me`(J y<
} $[P>nRhW
public int getCountId(){ Ig6>+Mw
return countId; mLn =SU{#
} MF^I] 7_
} P=9Zm
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CountCache.java B.J4}Ua
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/* v]HiG_C
* CountCache.java U%na^Wu
* -/#tQ~{gs
* Created on 2007年1月1日, 下午5:01 <ArP_!
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* C&ivjFf
* To change this template, choose Tools | Options and locate the template under v`$9;9
* the Source Creation and Management node. Right-click the template and choose u!DSyHR
'
* Open. You can then make changes to the template in the Source Editor. c=p @l<)
*/ ;{~F7:i
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package com.tot.count; >AW=N
import java.util.*; '2%/h4jY
/** A
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* KCed!OJ+
* @author hOx">yki
*/ 3f:I<S7
public class CountCache { U;:,$]+
public static LinkedList list=new LinkedList(); 2JYt.HN
/** Creates a new instance of CountCache */ YA>du=6y\
public CountCache() {} ^50/.Z>
public static void add(CountBean cb){ ;pNHT*>u,
if(cb!=null){ <`q|6XWL
list.add(cb); _k@{>
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} a".uS4x
} Wwf#PcC]
} Mr(~
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CountControl.java |8"~ou:.
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/* VBssn]w
* CountThread.java 3EcmNwr
* <z|? C
* Created on 2007年1月1日, 下午4:57 G?]E6R
* tH"SOGfSt
* To change this template, choose Tools | Options and locate the template under q'?:{k$%
* the Source Creation and Management node. Right-click the template and choose #7U,kTj9
* Open. You can then make changes to the template in the Source Editor. (K+TqJw
*/ MNiu5-g5
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package com.tot.count; (;a
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import tot.db.DBUtils; Tf"DpA!_
import java.sql.*; >M^
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/** wDZFOx0#8
* DwZt.*
* @author q$`:/ ehw
*/ LxVd7r VY6
public class CountControl{ ?Y'S
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private static long lastExecuteTime=0;//上次更新时间 u
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 O`dob&C
/** Creates a new instance of CountThread */ lq_W;L
public CountControl() {} dTaR8i
public synchronized void executeUpdate(){ As (C8C<
Connection conn=null; h& (@gU`A
PreparedStatement ps=null; r<O^uz?Di
try{ rA9x T`
conn = DBUtils.getConnection(); C<fNIc~.
conn.setAutoCommit(false); *ftJ(
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); fT8Id\6js
for(int i=0;i<CountCache.list.size();i++){ EBM\p+x&
CountBean cb=(CountBean)CountCache.list.getFirst(); 64\Z OG\,
CountCache.list.removeFirst(); ('uYA&9
ps.setInt(1, cb.getCountId()); $YSD%/c
ps.executeUpdate();⑴ fwAN9zs
//ps.addBatch();⑵ C)z[Blt
} &u"*vG (U[
//int [] counts = ps.executeBatch();⑶ vO{ijHKE
conn.commit(); Ytx+7OLe
}catch(Exception e){ VJCh5t*
e.printStackTrace(); BPrA*u}T
} finally{ 6EK+] 0
try{ ja7Zv[
if(ps!=null) { %TG$5')0
ps.clearParameters(); 0 \LkJ*i
ps.close(); =pcj{B{qa
ps=null; >Fld7;L?<
} Mn~A;=%qF
}catch(SQLException e){} 7Nwi\#o
DBUtils.closeConnection(conn); 0v0Y(
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} >W'SG3Hmc
} 2c%}p0<;|?
public long getLast(){ @?Y^=0
return lastExecuteTime; YC=BP5^
} R/^JyL
public void run(){ cT0utR&
long now = System.currentTimeMillis(); X_'.@q<!CV
if ((now - lastExecuteTime) > executeSep) { Z{p6Q1u
//System.out.print("lastExecuteTime:"+lastExecuteTime); Sc6wC H
//System.out.print(" now:"+now+"\n"); X=\#n-*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); C3@.75-E
lastExecuteTime=now; I I>2\d|
executeUpdate(); sjTsaM;<
} $xu?zd"
else{ ;wQWt_OtuJ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); % C
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} :GK{JP
} `FJnR~d
} fr#lH3
//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 `8dE8:#Y
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类写好了,下面是在JSP中如下调用。 ri JyH;)
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<% U*&ZQw
CountBean cb=new CountBean(); GmL |7 6
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); o@>c[knJ
CountCache.add(cb); Etu>z+P!
out.print(CountCache.list.size()+"<br>"); R\.huOJh
CountControl c=new CountControl(); doR'=@ W
c.run(); (v4
out.print(CountCache.list.size()+"<br>"); mLkZ4OZ
%>