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: oyiEOC
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CountBean.java swntz
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/* {Ug?k<h7|
* CountData.java ^duNEu0*
* _jQ"_Ff
* Created on 2007年1月1日, 下午4:44 4jfkCU
* i"p)%q~ z
* To change this template, choose Tools | Options and locate the template under HY4X;^hF
* the Source Creation and Management node. Right-click the template and choose ML^c-xY(
* Open. You can then make changes to the template in the Source Editor. TXWi5f[
*/ a2 e-Q({
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package com.tot.count; FY|.eY_7 {
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/** =X'i^Q
* y2bL!Y<s9
* @author !ZPaU11
*/ a$y=+4L
public class CountBean { : " 9F.U
private String countType; ]L@VpHEj
int countId; -^`]tF`M
/** Creates a new instance of CountData */ QWp,(Mv:r
public CountBean() {} VImcW;Xa
public void setCountType(String countTypes){ X>(?
this.countType=countTypes; N{U``LV
} @kw#\%Uz
public void setCountId(int countIds){ %6}S1fuA
this.countId=countIds; \BOZhXfl'
} '8R5?9"
public String getCountType(){ wuSp+?{5k
return countType; u=JI 1
} RcIGIt
public int getCountId(){ t."hAvRL
return countId; %"Q{|}
} y w)q3zC
} &=oW=g 2
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CountCache.java /B73|KB+
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/* g.ty#Z=:
* CountCache.java R}'kF63u*
* 6Lk<VpAa
* Created on 2007年1月1日, 下午5:01 [XK Ke
* TR/'L!EE
* To change this template, choose Tools | Options and locate the template under |!NKKvf
* the Source Creation and Management node. Right-click the template and choose L
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* Open. You can then make changes to the template in the Source Editor. k7yQEU
*/ 1bs8fUPB3
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package com.tot.count; >bWx!M]
import java.util.*; ?kEcYD
/** m{4e+&S|
* L8("1_
* @author 0h nTHlk
*/ {_ti*#
public class CountCache { ">PpC]Y1
public static LinkedList list=new LinkedList(); phr6@TI
/** Creates a new instance of CountCache */ #K:|@d
public CountCache() {} `@eo <6
public static void add(CountBean cb){ Y>LgpO.
if(cb!=null){ E~Eh'>Y(B
list.add(cb); + Bk"
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} |d\rCq >
} l ps
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} VDq4n;p1
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CountControl.java H. U wM
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/* E#?*6/
* CountThread.java S(<r-bV<
* %upnXRzw
* Created on 2007年1月1日, 下午4:57 EkS7j>:
* q|,cMPS3
* To change this template, choose Tools | Options and locate the template under HO%atE$>
* the Source Creation and Management node. Right-click the template and choose bkk1_X
* Open. You can then make changes to the template in the Source Editor. jkw:h0hX
*/ <+ 0cQq=2
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package com.tot.count; ENW>bS8e`
import tot.db.DBUtils; "X4L+]"$g
import java.sql.*; ~RGZY/4
/** wmbjL=f
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* ~Vq<nkWS
* @author e]R`B}vO
*/ \-3\lZ3qj
public class CountControl{ V9qZa
private static long lastExecuteTime=0;//上次更新时间 )2t!=
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 foY=?mbL
/** Creates a new instance of CountThread */ c^0YuBps[
public CountControl() {} gn"Y?IZ?
public synchronized void executeUpdate(){ 2(~Y ^_
Connection conn=null; 9i4!^DM_
PreparedStatement ps=null; DtkY;Yl
try{ ?0k(wiF
conn = DBUtils.getConnection(); DrE
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conn.setAutoCommit(false); JRQ{Q"`)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 0ant0<
for(int i=0;i<CountCache.list.size();i++){ Fr/3Qp@S
CountBean cb=(CountBean)CountCache.list.getFirst(); ? ->:,I=<~
CountCache.list.removeFirst(); dm;H0v+Y'
ps.setInt(1, cb.getCountId()); J!r,ktO^U?
ps.executeUpdate();⑴ ivL}\~L
//ps.addBatch();⑵ vowU+Y
} y+D 3(Bsn
//int [] counts = ps.executeBatch();⑶ 2D|2/ >[
conn.commit(); '6U~|d
}catch(Exception e){ M ,qX
e.printStackTrace(); ;4XvlcGo
} finally{ LDDeZY"xd
try{ ) wkh
if(ps!=null) { ILdRN
ps.clearParameters(); 5c50F{
ps.close(); i
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ps=null; jM`)Nd
} P&PPX#%
}catch(SQLException e){} ]C.x8(2!f
DBUtils.closeConnection(conn); :EOx>Pf_9)
} ~<b/%l>h1
} O 1TJJ8
public long getLast(){ ~P&Brn"=Rs
return lastExecuteTime; `CCuwe<v
} aRFLh
public void run(){
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long now = System.currentTimeMillis(); n#@/A
if ((now - lastExecuteTime) > executeSep) { VA4>!t)
//System.out.print("lastExecuteTime:"+lastExecuteTime); J[E_n;d1
//System.out.print(" now:"+now+"\n"); _hP siZY9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); N[e QT
lastExecuteTime=now; cBICG",TA
executeUpdate(); H:9Z.|{Gv
} 566vjE
else{ m\a_0!K
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); R?aE:\A
} ,#=ykg*~/
} 9=,^^,q
} !e~Yp0gX#
//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 K:PzR,nn
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类写好了,下面是在JSP中如下调用。 }$DLa#\-
hjCFN1 #Sa
<% l#7].-/
CountBean cb=new CountBean(); GdZ_
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); X r7pFw
CountCache.add(cb); m)G=4kK52-
out.print(CountCache.list.size()+"<br>"); RQ?T~ASs
CountControl c=new CountControl(); /18Z4TA
c.run(); R#j-Z#/"
out.print(CountCache.list.size()+"<br>"); rMDo5Z2
%>