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: 1+s;FJ2}
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CountBean.java O0.*Pmt
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/* %ET+iIhK
* CountData.java g7H(PF?
* Z T%5T}i
* Created on 2007年1月1日, 下午4:44 /N{*"s2)
* (LCfUI6;
* To change this template, choose Tools | Options and locate the template under })%{AfDRF
* the Source Creation and Management node. Right-click the template and choose h_'*XWd@
* Open. You can then make changes to the template in the Source Editor. }K(TjZR
*/ 9*M,R,y
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package com.tot.count; z b3tIRH
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/** a7opCmL
* l/5
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* @author ^cWnF0)j.
*/ oB7_O-3z
public class CountBean { _[BP0\dPW
private String countType; hZb_P\1X
int countId; \FaP|28h
/** Creates a new instance of CountData */ @0''k
public CountBean() {} jP.dDYc
public void setCountType(String countTypes){ {JLtE{
this.countType=countTypes; '&b+R`g'
} TWTb?HP
public void setCountId(int countIds){ f o3}W^0
this.countId=countIds; :A;RH
} d=/F}yP~?s
public String getCountType(){
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return countType; $`8wJf9@w
} {qVZNXDn
public int getCountId(){ z1a7*)8P
return countId; -9?]IIVb
} ;_=&-mz
} o mx=
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CountCache.java ;'1d1\wiDQ
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/* xE}>,O|'q
* CountCache.java %BODkc Zh
* UiNP3TJ'L
* Created on 2007年1月1日, 下午5:01 "[N!m1i:{
* ;tf=gdX;
* To change this template, choose Tools | Options and locate the template under DY*N|OnqJ
* the Source Creation and Management node. Right-click the template and choose EU#^7
* Open. You can then make changes to the template in the Source Editor. |7~<Is~*
*/ lB4WKn=?Kl
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package com.tot.count; 7yQ4*UB
import java.util.*; Lw,h+@0
/** "dlVk~
* /-s6<e!
* @author zQ PQ
*/ E{(;@PzE
public class CountCache { xIn:ZKJ'
public static LinkedList list=new LinkedList(); XWw804ir
/** Creates a new instance of CountCache */ Zd+bx*rD
public CountCache() {} (@YG~0
public static void add(CountBean cb){ ;.C\Ss<>*
if(cb!=null){ q3`u1S7Z7
list.add(cb); K sCyFp
} :!QAC@
} L/[K"
} V]^$S"Tv
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CountControl.java An@t?#4gxi
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/* xSu >
* CountThread.java ,r}6iFu
* 5V-I1B&
* Created on 2007年1月1日, 下午4:57 wIgS3K
* Bw.i}3UT6
* To change this template, choose Tools | Options and locate the template under 4p wH>1
* the Source Creation and Management node. Right-click the template and choose -\MG}5?!
* Open. You can then make changes to the template in the Source Editor. FI.\%x
*/ X>^fEQq"
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package com.tot.count; O.M1@w]
import tot.db.DBUtils; 6u%&<")4HP
import java.sql.*; 7p[n
/** qP
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* '"Nr, vQo
* @author ~ri5zb20
*/ naNghGQ
public class CountControl{
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private static long lastExecuteTime=0;//上次更新时间 2<6UwF
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 p7~!z.)o
/** Creates a new instance of CountThread */ 1;iUWU1@
public CountControl() {} (k P9hcV
public synchronized void executeUpdate(){ (m$Y<{)2
Connection conn=null; +`15le`R
PreparedStatement ps=null; p<%d2@lp
try{ 4ppz,L,4
conn = DBUtils.getConnection(); JGZBL{8
conn.setAutoCommit(false); E{@[k%,_
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); I+(nu47ZT
for(int i=0;i<CountCache.list.size();i++){ qgB_=Q#E
CountBean cb=(CountBean)CountCache.list.getFirst(); 9H~n_
CountCache.list.removeFirst(); -g<oS9
ps.setInt(1, cb.getCountId()); n+p }\msH
ps.executeUpdate();⑴ &&%H%9
//ps.addBatch();⑵ 9M ]_nP Y
} {{1G`;|v9
//int [] counts = ps.executeBatch();⑶ =MWHJ'3-/
conn.commit(); }B^tL$k
}catch(Exception e){ g2]Qv@nxw
e.printStackTrace(); u@444Vzg
} finally{ `@%LzeGz
try{ ` %}RNC
if(ps!=null) { ]###w;
ps.clearParameters(); 4e
ps.close(); y>LBl]
ps=null; 06jQE2z2R
} ,)io5nZF
}catch(SQLException e){} 5twhm
DBUtils.closeConnection(conn); F[MFx^sT{
} MfkZ
} SfR%s8c`
public long getLast(){ _dU\JD
return lastExecuteTime; Xc.`-J~Il
} {G-kNU
public void run(){ 1mJHued=6
long now = System.currentTimeMillis(); sRfcF`7
if ((now - lastExecuteTime) > executeSep) { zeRyL3fnmb
//System.out.print("lastExecuteTime:"+lastExecuteTime); }a/Cro.~4
//System.out.print(" now:"+now+"\n"); @]0%L0u
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); (%9$! v{3
lastExecuteTime=now; 0 {mex4
executeUpdate(); 5R7DDJk
} (5~h"s
else{ 1x^GWtRp
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); D'4\*4is
} Hp?/a?\Xm
} #E]59_
} <N@Gu!N8
//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
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类写好了,下面是在JSP中如下调用。 92{\B-
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<% .C(tMF]D,
CountBean cb=new CountBean(); !'Kjx
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ]^]wP]R_
CountCache.add(cb); t<qiGDJ<d
out.print(CountCache.list.size()+"<br>"); u:EiwRW
CountControl c=new CountControl(); N g,j#
c.run(); V.Mry`9-
out.print(CountCache.list.size()+"<br>"); TC"<g
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