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: 9k8ftxB^
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CountBean.java cAq>|^f0a
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/* &09z`*,
* CountData.java u4TU"r("A
* >!O3 jb k
* Created on 2007年1月1日, 下午4:44 Nf8."EDUW
* & V:q}Q
* To change this template, choose Tools | Options and locate the template under 1~:7W
* the Source Creation and Management node. Right-click the template and choose [^xLK
* Open. You can then make changes to the template in the Source Editor. xc dy/J&
*/ y~'F9E!i
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package com.tot.count; *O-1zIlp
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/** &.z: i5&o!
* MMCac6;Aea
* @author L6`(YX.:
*/ Eyi^N0
public class CountBean { `s#0/t
private String countType; {a`t1oX(
int countId; Jj+|>(P
/** Creates a new instance of CountData */ >Ia{ZbQV
public CountBean() {} H~%HTl
public void setCountType(String countTypes){ s\ft:a@
this.countType=countTypes; $z,lq#zzl
} j<H`<S
public void setCountId(int countIds){ lx*"Pj9hho
this.countId=countIds; ?dMyhU}
} z{:T~s
public String getCountType(){ *0zdI<Oe
return countType; MGpP'G:v
} D /ysS$!{
public int getCountId(){ O{Bll;C
return countId; e!
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} Yqz(@( %
} O="#yE)
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CountCache.java :0G "EM4
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/* {~NiGHY
* CountCache.java >qh8em
* rlG&wX
* Created on 2007年1月1日, 下午5:01 ~]X4ru5,4
* S^nshQI
* To change this template, choose Tools | Options and locate the template under l
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* the Source Creation and Management node. Right-click the template and choose gi!{y
* Open. You can then make changes to the template in the Source Editor. g4USKJ19.
*/ r0kJx$f
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package com.tot.count; @+II@[_lT
import java.util.*; iu!j#VO
/** /V@~Vlww
* Ny|2Fcs
* @author \|
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*/ \49LgN@\
public class CountCache { dw{L,u`68
public static LinkedList list=new LinkedList(); t\44 Pu%
/** Creates a new instance of CountCache */ ,)%al76E
public CountCache() {} 0>hV?A
public static void add(CountBean cb){ F
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if(cb!=null){ $s$j</.q
list.add(cb); h+EG)
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} d]Y-^&]{]
} N8a+X|3]0
} p6~\U5rXm
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CountControl.java
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/* 1haH2F^q3
* CountThread.java #B7_5y^
* qOaI4JP@
* Created on 2007年1月1日, 下午4:57 _ dFZR
* o.Ld.I)
* To change this template, choose Tools | Options and locate the template under 9pAklD 4
* the Source Creation and Management node. Right-click the template and choose r #H(kJu,
* Open. You can then make changes to the template in the Source Editor. 5J!ncLNm{
*/ H9nVtS{x
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package com.tot.count; !Ld0c4
import tot.db.DBUtils; Hc.r/
import java.sql.*; (p4|,\+
/** 9_yO6)`
* }{"a}zOl
* @author yVA<-PlS<
*/ lm'L-ZPN
public class CountControl{ dH4wyd`
private static long lastExecuteTime=0;//上次更新时间 Y rq-(
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 a1V+doC
/** Creates a new instance of CountThread */ i,HafY
public CountControl() {} ygt7;};!
public synchronized void executeUpdate(){ tXj28sh$
Connection conn=null; awP
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PreparedStatement ps=null; |+Gv)Rvp
try{ >q+o
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conn = DBUtils.getConnection(); J9s4lsea
conn.setAutoCommit(false); vY|{CBGbd
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?");
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for(int i=0;i<CountCache.list.size();i++){ AgKG>%0
CountBean cb=(CountBean)CountCache.list.getFirst(); !OwRx5
CountCache.list.removeFirst(); b[+G+V
ps.setInt(1, cb.getCountId()); !63>I I
ps.executeUpdate();⑴ U~{fbS3,
//ps.addBatch();⑵ ut26sg{s(
} Gao8!OaQ
//int [] counts = ps.executeBatch();⑶ q2Xm~uN`)
conn.commit(); a/d'(]
}catch(Exception e){ kMD:~V
e.printStackTrace(); Q'?{_
} finally{ Pl|e?Np
try{ -$Y@]uf^
if(ps!=null) { +
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ps.clearParameters(); fq*.4s
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ps.close(); Y{c_5YYf
ps=null; zY?GO"U"
} W)WL1@!Z
}catch(SQLException e){} 6=ukR=]v
DBUtils.closeConnection(conn); qs\O(K8
} A2Je*Gz
} a.P7O!2Lp
public long getLast(){ }T<[JXh=J
return lastExecuteTime; );4lM%]eb
} [S{KGe:g
public void run(){ $dr=M(&
long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { [x}]sT`#a
//System.out.print("lastExecuteTime:"+lastExecuteTime); 34Q;& z\e
//System.out.print(" now:"+now+"\n"); c\2+f7o@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `[T|Ck5
lastExecuteTime=now; N}ur0 'J0
executeUpdate(); !Jh/M^
} Y\e,#y
else{ ]Z/<HP$#
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); z#qlu=
} &,?bX])
} f{ZOH<"Lo
} 4;G:.k!K
//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 tvNh@it:F
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类写好了,下面是在JSP中如下调用。 om$x;L6
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<%
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CountBean cb=new CountBean(); XXuIWIhm
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); dB{o-R
CountCache.add(cb); pJM~'tlHV
out.print(CountCache.list.size()+"<br>"); 3#)I 7FG
CountControl c=new CountControl(); Tac7+=T
c.run(); JffjGf-o
out.print(CountCache.list.size()+"<br>"); N[$bP)h7
%>