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: ZgzYXh2
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CountBean.java KeC&a=HL
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/* ksqb& ux6
* CountData.java fp"GdkO#}i
* R1:7]z0B
* Created on 2007年1月1日, 下午4:44 DEenvS`,P
* >LFj@YW_)
* To change this template, choose Tools | Options and locate the template under Nw3IDy~T
* the Source Creation and Management node. Right-click the template and choose x=Ez hq]X
* Open. You can then make changes to the template in the Source Editor. T(*A0
*/ uq]E^#^
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package com.tot.count; GS!1K(7
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/** Sr6?^>A@t
* bB.Yq3KI
* @author =ZARJ40L
*/ 3>^S6h}o
public class CountBean { l{3ZN"`I
private String countType; jTok1k
int countId; l @r`NFWD@
/** Creates a new instance of CountData */ RgVg~?A@
public CountBean() {} '/F~vSQsR
public void setCountType(String countTypes){ o@|kq1m8
this.countType=countTypes; [i]%PVGW
} ]Ai!G7s8P
public void setCountId(int countIds){ E._ [P/PB
this.countId=countIds; fH_Xm :%
} I8:G:s:
public String getCountType(){ 'i8?]`
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return countType; 4"V6k4i5
} S)A;!}RK6
public int getCountId(){ Ns[.guWu-
return countId; %VgK::)r
} d#HN'(2t
} JU-eoB}m
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CountCache.java $/P\@|MqYQ
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/* 9CHn6 v ~)
* CountCache.java P6 mDwR
*
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* Created on 2007年1月1日, 下午5:01 El3Ayd3
* hmtDw,j
* To change this template, choose Tools | Options and locate the template under !9=Y(rb
* the Source Creation and Management node. Right-click the template and choose ZF;s`K)
* Open. You can then make changes to the template in the Source Editor. izr
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*/ xh!aB6m8R
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package com.tot.count; 9B1bq #
import java.util.*; jD_B&MQz
/** 2v1dSdX,W
* {=kW?
* @author U{-[lpd
*/ $
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public class CountCache { ig:z[k?
public static LinkedList list=new LinkedList(); _K|?;j#x0k
/** Creates a new instance of CountCache */ Wi!$bL`l
public CountCache() {} O9MBQNwjA
public static void add(CountBean cb){ C<iOa)_@Q
if(cb!=null){ ${, !L l7)
list.add(cb); +Ram%"Zwh
} fZJ O}
} ZZ F\;
} w'!J
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CountControl.java o|c"W}W
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/* B7BikxUa
* CountThread.java 05vu{>
* C)qP9uW
* Created on 2007年1月1日, 下午4:57 8*yky
* `v$Bib)
* To change this template, choose Tools | Options and locate the template under W|[k]A` 2
* the Source Creation and Management node. Right-click the template and choose %Z6\W;
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* Open. You can then make changes to the template in the Source Editor. ?VT
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*/ uB uwE6
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package com.tot.count; |oJ R+
import tot.db.DBUtils; ,V:RE y
import java.sql.*; U})Z4>[bvt
/** Ol.
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* 1`8(O >5
* @author oq }Q2[.b
*/ vH9Gf
public class CountControl{ t>>\U X
private static long lastExecuteTime=0;//上次更新时间 wKs-<b%;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 yzmwNsu
/** Creates a new instance of CountThread */ wPU<jAQyp
public CountControl() {} <S%kwS
public synchronized void executeUpdate(){ @IwVR
Connection conn=null; QG=&{-I~[3
PreparedStatement ps=null; SB` "%6
try{ " ^:$7~%bA
conn = DBUtils.getConnection(); |MXv
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conn.setAutoCommit(false); 4 jeUYkJUM
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Pxm~2PAm
for(int i=0;i<CountCache.list.size();i++){ o+Kh2;$)
CountBean cb=(CountBean)CountCache.list.getFirst(); ;P4tqY@
CountCache.list.removeFirst(); ym)`<[T
ps.setInt(1, cb.getCountId()); Z
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ps.executeUpdate();⑴ 9ApGn!`
//ps.addBatch();⑵ E$84c+
} C]+T5W\"<B
//int [] counts = ps.executeBatch();⑶ 7Y(ySW
conn.commit(); L]HYk}oD.
}catch(Exception e){ tqo!WuZAj
e.printStackTrace(); Z'sO9Sg8>
} finally{ ';bovh@*
try{ ZM%z"hO9R
if(ps!=null) { ,0Y5O?pu\
ps.clearParameters(); 4?^t=7N
ps.close(); F
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ps=null; c;e2=
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} 5U/1Z{
}catch(SQLException e){} f~D>
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DBUtils.closeConnection(conn); NTtRz(
} :+>:>$ao
}
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public long getLast(){ NCM&6<_
return lastExecuteTime; :Gz# 4k
} zl!`*{T{
public void run(){ U'acVcD
long now = System.currentTimeMillis(); 1$Pn;jg:
if ((now - lastExecuteTime) > executeSep) {
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//System.out.print("lastExecuteTime:"+lastExecuteTime); KGm"-W
//System.out.print(" now:"+now+"\n"); W<D(M.61A
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 7+I2"Hy
lastExecuteTime=now; {E~MqrX
executeUpdate(); pQY.MZSA
} }3Y3f).ZW
else{ ?=uw0~O[
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); b]h]h1~hHH
} o[!g,Gmoh
} 4;ig5'U,
} zSiSZMP"
//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 Y Hv85y
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类写好了,下面是在JSP中如下调用。 X;ZR"YgT
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<% \k|ZbCWg
CountBean cb=new CountBean(); &n:F])`2
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); SdfrLdi}Y
CountCache.add(cb); ]{[VTjC7rY
out.print(CountCache.list.size()+"<br>"); Z<#beT6
CountControl c=new CountControl(); .#b! #
c.run(); ?_F,HhQ
out.print(CountCache.list.size()+"<br>"); 0F<O \
%>