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: fwQ%mU+
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CountBean.java [P{Xg:0
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/* }H,A
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* CountData.java LVLh&9
* j{P,(-
* Created on 2007年1月1日, 下午4:44 WiviH#hF
* I>-jKSkwc
* To change this template, choose Tools | Options and locate the template under ?I 1@:?Qi
* the Source Creation and Management node. Right-click the template and choose _bks*.9}3b
* Open. You can then make changes to the template in the Source Editor. 5J&n<M0G1
*/ TCF[iE{
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package com.tot.count; a}c(#ZLs
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/** D#m+w
* IW1]H~1w
* @author 28BiuxVW
*/ 1=(i{D~
public class CountBean { r$\g6m
private String countType; ~0 FqY&4
int countId;
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/** Creates a new instance of CountData */ xG}eiUbM`
public CountBean() {} +ic~Sar
public void setCountType(String countTypes){ 0 q3<RX>M%
this.countType=countTypes; b8v$*{
} I@L-%#@R1
public void setCountId(int countIds){ jv|IV
this.countId=countIds; kxUGd)S
}
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public String getCountType(){ {Ue6DK%
return countType; "msg./iC
} a5)[?ol
public int getCountId(){ v*BA\&
return countId; Iwn@%?7
} _mkI;<d]$T
} 7_Q86o
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CountCache.java *,n7&
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/* (wY%$kW4
* CountCache.java %mYIXsuH
* -=sxbs.aA
* Created on 2007年1月1日, 下午5:01 \A~
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* ~V|!\CB
* To change this template, choose Tools | Options and locate the template under <s7{6n')
* the Source Creation and Management node. Right-click the template and choose g<dCUIbcQ
* Open. You can then make changes to the template in the Source Editor. ~!nd'{{9
*/ #U_u~7?H$
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package com.tot.count; PvB?57wkF
import java.util.*; F'~/
/** P`%ppkzV6
* *HXq`B
* @author yED^/=\)}
*/ q-3KF
public class CountCache { +|8Lt[^ux
public static LinkedList list=new LinkedList(); k?8W2fC
/** Creates a new instance of CountCache */ CM#EA"9
public CountCache() {} &4%J35~
public static void add(CountBean cb){ FXSDN268
if(cb!=null){ aw4+1.xy
list.add(cb); T8(wzs
} ^+wzm2i
} t/D
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} 1*jL2P]D
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CountControl.java 7cy~qg
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/* cU6#^PFu
* CountThread.java QO>*3,(H,q
* 1c4%g-]7
* Created on 2007年1月1日, 下午4:57 ).boe& .
* >>8w(PdTn%
* To change this template, choose Tools | Options and locate the template under : [9'nR
* the Source Creation and Management node. Right-click the template and choose ["IJh
* Open. You can then make changes to the template in the Source Editor. !?>)[@2
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*/ H.mG0x`M"E
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package com.tot.count; 2&d&$Jg
import tot.db.DBUtils; )/AvWDKvO
import java.sql.*; .0-m=3mp2
/** o'4@]ae
* S- \lN|
* @author '9dtIW6E
*/ /
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public class CountControl{ //,'oh~W
private static long lastExecuteTime=0;//上次更新时间 \|t0~sRwh
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 KEN-G
/** Creates a new instance of CountThread */ n6Zx0ad?
public CountControl() {} )89jP088V
public synchronized void executeUpdate(){ [L(l++.z
Connection conn=null; 7tpZE+OX
PreparedStatement ps=null; pdHb
try{ (R<4"QbE
conn = DBUtils.getConnection(); Rx"Qwi, \U
conn.setAutoCommit(false); l1qwT0*6>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); B3t>M)
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for(int i=0;i<CountCache.list.size();i++){ 1Qu,]i`
CountBean cb=(CountBean)CountCache.list.getFirst(); gc~h!%'.I
CountCache.list.removeFirst(); uPXqTkod
ps.setInt(1, cb.getCountId()); &s;^q
ps.executeUpdate();⑴ 7qz-RF#s8
//ps.addBatch();⑵ N8q Z{CWn
} {wXN kq
//int [] counts = ps.executeBatch();⑶ IpXhb[UZ?
conn.commit(); /xbZC{R
}catch(Exception e){ &RrQ()<as
e.printStackTrace(); z=_{jjs
} finally{ =M#?* e
try{ <'_GQM`G
if(ps!=null) { y;Ln ao7i
ps.clearParameters(); [s{:}ZuKc
ps.close(); d)ZSzq
ps=null; %pkq ?9
} BQ:Kx _
}catch(SQLException e){} L)'rM-nkFh
DBUtils.closeConnection(conn); PEt8,,x<"
} WN/#9]` P
} I=yj
public long getLast(){ %u0;.3Gw
return lastExecuteTime; *9ub.:EUwV
} f1$mh1J W
public void run(){ }C"*ACjF
long now = System.currentTimeMillis(); l1Q+hz5"*U
if ((now - lastExecuteTime) > executeSep) { yaLW(@
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7U`S9DDwq
//System.out.print(" now:"+now+"\n"); ^!F5Cz 48
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [(F<|f:n
lastExecuteTime=now; F'$S!K58
executeUpdate(); $jh>zf
} O)JUY*&I5
else{ EJ ~kZ3
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Q9xx/tUW
} )$h9Y
} U"Hquo
} 3t{leuO'
//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 lO:{tV
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类写好了,下面是在JSP中如下调用。 K!c@aD:#
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<% tZ
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CountBean cb=new CountBean(); eoe^t:5&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /+t[,
CountCache.add(cb); n=o'ocdS)
out.print(CountCache.list.size()+"<br>"); *m&:
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CountControl c=new CountControl(); 6Hbf9,vI
c.run(); `h9)`*
out.print(CountCache.list.size()+"<br>"); V<V\0n!0
%>