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: .*oL@iX
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CountBean.java %@)q=*=y
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/* _ eBNbO_J
* CountData.java \_R<Q?D+
* aBY&]6^-
* Created on 2007年1月1日, 下午4:44 k{F6WQ7
* 0Qvr
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* To change this template, choose Tools | Options and locate the template under AI{0;0
* the Source Creation and Management node. Right-click the template and choose #4LTUVH
* Open. You can then make changes to the template in the Source Editor. Op~:z<z
*/ U"Bge\6x=
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package com.tot.count; ;Wk3>\nT-
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/** C\BKdx5;
* A=|a!N/
* @author P(8
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*/ |P|2E~[r
public class CountBean { O_th/hl
private String countType; g +gcH
int countId; ~-lUS0duh
/** Creates a new instance of CountData */ <'sm($.2
public CountBean() {} 'w72i/
public void setCountType(String countTypes){ ,H/O"%OJ
this.countType=countTypes; upk_;ae
} Wrp+B[{r\
public void setCountId(int countIds){ ^*$!9~
this.countId=countIds; w?nSQBz$
} 06.8m;{N
public String getCountType(){ $qg2@X.
return countType; Q$`uZ
} $kmY[FWu?
public int getCountId(){ Tw`dLK?
return countId; oVbs^sbRH
} `#`C.:/n
} -p7
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CountCache.java |)%H_TXTy
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/* J
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* CountCache.java \' A-
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* j%]sym
* Created on 2007年1月1日, 下午5:01 HEa7!h[a'
* zYdieE\-
* To change this template, choose Tools | Options and locate the template under ,`a8@
* the Source Creation and Management node. Right-click the template and choose Em{;l:;(W
* Open. You can then make changes to the template in the Source Editor. W}zq9|p
*/ UM21Cfqex
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package com.tot.count; :2vuc!Pu
import java.util.*; j8^#698X
/** p*@t$0i
* j%Uoigi
* @author ObreDv^,
*/ \{a5]G(4s
public class CountCache { ;tA$
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public static LinkedList list=new LinkedList(); 7u:kR;wk
/** Creates a new instance of CountCache */ &><b/,]
public CountCache() {} upeioC q
public static void add(CountBean cb){ xy&*s\=:
if(cb!=null){ wzoT!-_X
list.add(cb); PX/^*
} K~3Y8ca
} pg_H' 0R
} LZs'hA<L
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CountControl.java ]EDCs?,
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/* M5_t#[ [
* CountThread.java i 2uSPV!Tf
* P;'ZdZ(SLu
* Created on 2007年1月1日, 下午4:57 4:b'VHW.
* @PQd6%@
* To change this template, choose Tools | Options and locate the template under tk8\,!9Q
* the Source Creation and Management node. Right-click the template and choose L@Qvj-5e
* Open. You can then make changes to the template in the Source Editor. SsfC
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*/ CMv8n@ry
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package com.tot.count; /"~UGn]R
import tot.db.DBUtils; Q:y'G9b
import java.sql.*; .VUnOdI
/** _E6N*ORV
* D,=#SBJ :Z
* @author A
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*/ C,LosAd
public class CountControl{ 4mX?PKvbn
private static long lastExecuteTime=0;//上次更新时间 QJjk#*?,|
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %AWc`D
/** Creates a new instance of CountThread */ mZM7 4!4X
public CountControl() {} ]TcQGW@'
public synchronized void executeUpdate(){ _nX8f
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Connection conn=null; :B7U),T
PreparedStatement ps=null; #!#s7^%K&
try{ @+y,E-YTdV
conn = DBUtils.getConnection(); m] -cRf)9
conn.setAutoCommit(false); 3r,Kt&2$
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); V 7ZGT
for(int i=0;i<CountCache.list.size();i++){ uNw9g<g:V[
CountBean cb=(CountBean)CountCache.list.getFirst(); <nN# K{AH
CountCache.list.removeFirst(); AA=eWg
ps.setInt(1, cb.getCountId()); Wa&!1'
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ps.executeUpdate();⑴ "{t]~urLd
//ps.addBatch();⑵ SQx&4R.
} ~ ^
//int [] counts = ps.executeBatch();⑶ [/n@BK
conn.commit(); 8B(v6(h
}catch(Exception e){ Z`ww[Tbv~
e.printStackTrace(); k{UeY[,jb
} finally{ b&LAk-}[
try{ _ F|}=^Z`
if(ps!=null) { d/~g3n>|
ps.clearParameters(); u3tT=5.D
ps.close(); U)aftH
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ps=null; I:UDEoQo
} j4]3}t0q
}catch(SQLException e){} _z 5W*..
DBUtils.closeConnection(conn); {0-rnSjC
} x)eoz2E1
} l~DIV$>,Z
public long getLast(){ _jgtZ
return lastExecuteTime; ``6-
} Nv6"c<(L=
public void run(){ <dr2 bz
long now = System.currentTimeMillis(); D&~%w!
if ((now - lastExecuteTime) > executeSep) { Vry_X2
//System.out.print("lastExecuteTime:"+lastExecuteTime); IvI..#EzG
//System.out.print(" now:"+now+"\n"); \/V#,O
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); OIjSH~a.
lastExecuteTime=now; 'V&Uh]>
executeUpdate(); x',6VTz^
} &`tAQN*Z
else{ ~<s^HP2U{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); urCTP.F
} ~{vB2
} B<,7!:.II
} kOq8zYU|
//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 >s0![c oz
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类写好了,下面是在JSP中如下调用。 b`^Q ':^A
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<% dh&>E
CountBean cb=new CountBean(); [+xsX*+
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); HiH<'m"\.
CountCache.add(cb); PB8g4-?p6
out.print(CountCache.list.size()+"<br>"); U/|JAg#
CountControl c=new CountControl(); D>HbJCG4^
c.run(); $&KkZ
out.print(CountCache.list.size()+"<br>"); |d*a~T0
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