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: a"}?{
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CountBean.java +=*ZH`qX
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/* >R6Me*VR
* CountData.java ^
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* 5 gE
* Created on 2007年1月1日, 下午4:44 oY &r76
* AV?*r-vWL.
* To change this template, choose Tools | Options and locate the template under v vFX\j3
* the Source Creation and Management node. Right-click the template and choose h4]yIM`8d
* Open. You can then make changes to the template in the Source Editor. nlKWZYv
*/ N(Cfv3{
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package com.tot.count; ]cbY@U3!2
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/** zg|]Ic
* 2$|WXYY
* @author IRLT-
*/ <EJC.WWJa
public class CountBean { /"
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private String countType; R/iXO~/"J
int countId; SH"O<cDp
/** Creates a new instance of CountData */ jZ)1]Q2
public CountBean() {} {'JoVJKv
public void setCountType(String countTypes){ 0q81H./3
this.countType=countTypes; A^G%8 )\
} z.FO6y6L
public void setCountId(int countIds){ Vg0Rc t
this.countId=countIds; "gYn$4|R7*
} R{/nlS5
public String getCountType(){ vU::dr
return countType; J 5~bs*a8
} ">|fB&~A
public int getCountId(){ ?me0J3u_
return countId; Bc$t`PI
} +Bgy@.a?
} VCtj8hKDr
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CountCache.java ZPHB$]ri
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/* )jvYJ9s
* CountCache.java *?cE]U6;
* 0P z"[
* Created on 2007年1月1日, 下午5:01 2 g,UdG
* yy@g=<okt\
* To change this template, choose Tools | Options and locate the template under I;9>$?t[
* the Source Creation and Management node. Right-click the template and choose cZi/bIh
* Open. You can then make changes to the template in the Source Editor. qn:3s
*/ +eQg+@u
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package com.tot.count; !CUrpr/*
import java.util.*; ~'n3],o?
/** f/aSqhAW
* a(QYc?u
* @author w(0's'
*/ e~oI0%xl^
public class CountCache { wP29xV"5
public static LinkedList list=new LinkedList(); y\]:&)?&C^
/** Creates a new instance of CountCache */ v="i0lL_
public CountCache() {} It&$R`k
public static void add(CountBean cb){ :T.j;~
if(cb!=null){ p{gJVP#l'Z
list.add(cb); U*b1yxt
} .}C
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} yalT6
} Qt`}$]
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CountControl.java @uXF(KDX
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/* )ERmSWq/u
* CountThread.java < j^8L^
* ?U$H`[VF}
* Created on 2007年1月1日, 下午4:57 4-1=1)c*
* +G)L8{FY(
* To change this template, choose Tools | Options and locate the template under 7b7@"Zw*
* the Source Creation and Management node. Right-click the template and choose 8Th{(J_
* Open. You can then make changes to the template in the Source Editor. ,t2M ur
*/ 7,X5]U&A<x
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package com.tot.count; bLuAe
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import tot.db.DBUtils; WKek^TW4HE
import java.sql.*; >UlAae44
/** $}+t|`*q8]
* RDGefxv
* @author ,ELbm
*/ \iVb;7r)9:
public class CountControl{ vr/*z euA
private static long lastExecuteTime=0;//上次更新时间 O1[`2kj^HB
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;hzm&My
/** Creates a new instance of CountThread */ M<$a OW0
public CountControl() {} hhRUC&Y%V
public synchronized void executeUpdate(){ -y]e`\+[
Connection conn=null; u4hC/!
PreparedStatement ps=null; gqw
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try{ ^N#z&oh
conn = DBUtils.getConnection(); Q6%dM'fR
conn.setAutoCommit(false); s1~&PH^
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); F)XO5CBK
for(int i=0;i<CountCache.list.size();i++){ re[v}cB
CountBean cb=(CountBean)CountCache.list.getFirst(); *7cc4 wGQ
CountCache.list.removeFirst(); K FM x(fD
ps.setInt(1, cb.getCountId()); =zBc@VTp
ps.executeUpdate();⑴ c{4Y?SSx
//ps.addBatch();⑵ 0q}k"(9
} GE?M. '!{{
//int [] counts = ps.executeBatch();⑶ 6)5Akyz4V
conn.commit(); A}"aH
}catch(Exception e){ fRlO.!0(
e.printStackTrace(); : ZehBu
} finally{ *{TB<^ *
try{ 9\f%+?p
if(ps!=null) { pT ]: TRPS
ps.clearParameters(); 'Sk-L
5
ps.close(); z"D'rHxy
ps=null; Lgr(j60s
} ;fiH=_{us
}catch(SQLException e){} 9IfeaoZZ4q
DBUtils.closeConnection(conn); so=Ux2
} KcPI,.4{
} >_esLsPWh]
public long getLast(){ }:SWgPfc
return lastExecuteTime; 2d:IYCl4q
} J2Y
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public void run(){ }LYK:?_/
long now = System.currentTimeMillis(); _98
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if ((now - lastExecuteTime) > executeSep) { ^VL",Nt
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7^bde<0
//System.out.print(" now:"+now+"\n"); fC|NK+Xd`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); pXPLTGY<R+
lastExecuteTime=now; 'jnR<>N
executeUpdate(); lD+f{GR
} xr yXO(
else{ p#A{.6Pa:
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); w%' 8bH!
} vXI2u;=y
} T#OrsJdu
} {>r56\!F
//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 vHmsS\\~9
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类写好了,下面是在JSP中如下调用。 J
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<% 1^v?Ly8
CountBean cb=new CountBean(); CT2L }5L&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |i~Ab!*8n
CountCache.add(cb); + $Yld{i
out.print(CountCache.list.size()+"<br>"); $-*E
CountControl c=new CountControl(); yH<a;@C
c.run(); n,l{1 q
out.print(CountCache.list.size()+"<br>"); N.1@!\z@@
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