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: 3U)8P6Fz
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CountBean.java cy 4'q?r
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/* 9f,:j
* CountData.java YW<2:1A|
* F6p1 VFs
* Created on 2007年1月1日, 下午4:44 {%{GZ
* cAS_?"V
a
* To change this template, choose Tools | Options and locate the template under 0K ?(xB
* the Source Creation and Management node. Right-click the template and choose YHYB.H)
* Open. You can then make changes to the template in the Source Editor. {O)&5
*/ W#j,{&KVn
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package com.tot.count; ItADO'M
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/** 7h1gU
* fh#_Mj+y
* @author sE6J:m(
*/ \aIy68rH,
public class CountBean { %%6('wi
private String countType; yU,xcq~l
int countId; p'~5[JR:
/** Creates a new instance of CountData */ 31& .Lnq
public CountBean() {} tY=%@v'6?
public void setCountType(String countTypes){
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this.countType=countTypes; ,rQ)TT
} x-&v|w '
public void setCountId(int countIds){ r%d11[z
this.countId=countIds; a}fClI-u
} Yj6p19
public String getCountType(){ OPW"ABJ
return countType; ,<b|@1\k
} _~Vz+nT
public int getCountId(){ ~uadivli
return countId; e"#D){k#
} 4Z9wzQ>
} ~aAJn IO
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CountCache.java !"%sp6Wc
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/* o'/C$E4W
* CountCache.java 3^>a TU<Z
* od*Z$Hb>'
* Created on 2007年1月1日, 下午5:01 A(OfG&!
* uz3pc;0LPY
* To change this template, choose Tools | Options and locate the template under xY2_*#{.
* the Source Creation and Management node. Right-click the template and choose ROS"VV<
* Open. You can then make changes to the template in the Source Editor. g ypq`F
*/ [P=[hj;
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package com.tot.count; ^85n9a?8
import java.util.*; 8zDH<Gb
/** {$YD-bqY
* ih |Ky+ !
* @author FLI8r:
*/ p''"E$B/(
public class CountCache {
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public static LinkedList list=new LinkedList(); lk1Gs{(qhH
/** Creates a new instance of CountCache */ @B[Cc`IN"
public CountCache() {} l/zC##1+.
public static void add(CountBean cb){ ) Zo_6%
if(cb!=null){ 9,f<Nb(\
list.add(cb); 7G(f1Y
} @[tV_Z%,b
} 8sIA;r%S
} AAq=,=:R<
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CountControl.java &v5.;8u+OV
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/* 8KwCwv
* CountThread.java 8<g#$(a_E
* ^y0C5Bl;
* Created on 2007年1月1日, 下午4:57 )S}; k=kG
* ?7MwTi8{F
* To change this template, choose Tools | Options and locate the template under tQ/
#t<4D
* the Source Creation and Management node. Right-click the template and choose HJaw\zbL
* Open. You can then make changes to the template in the Source Editor. kEhm'
*/ `k]!6osZo
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package com.tot.count; L3GC[$S
import tot.db.DBUtils; PuZs5J3
import java.sql.*; cPsn]U
/** '&:1?i)
* {XD/8m(hN|
* @author 2FIR]@MQd
*/ FaE #\Q
public class CountControl{ hMeqs+
private static long lastExecuteTime=0;//上次更新时间 w zqd
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3
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/** Creates a new instance of CountThread */ 51G=RYay9
public CountControl() {} )R8%'X;U
public synchronized void executeUpdate(){ #3K,V8(
Connection conn=null;
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PreparedStatement ps=null; q@!'R{fu
try{ Afy .3T @)
conn = DBUtils.getConnection(); n5+S"
conn.setAutoCommit(false); -}X?2Q
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); MATgJ`lsy
for(int i=0;i<CountCache.list.size();i++){ !3I(4?G,
CountBean cb=(CountBean)CountCache.list.getFirst(); daB l%a=
CountCache.list.removeFirst(); 8HFXxpt[G
ps.setInt(1, cb.getCountId()); + sywgb)
ps.executeUpdate();⑴ &^7uv0M<y
//ps.addBatch();⑵ S6T!qH{6
} juMxl
//int [] counts = ps.executeBatch();⑶ tpa^k
conn.commit(); hB7pR"P
}catch(Exception e){ xd|~+4
e.printStackTrace(); !ASoXQRz
} finally{ g+ }s:9
try{ K6v
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if(ps!=null) { aM{@1mBm
ps.clearParameters(); 8pk#sJ51
ps.close(); f(6UL31
ps=null; P}hY{y'
} yS)-&t!;
}catch(SQLException e){} Q^lQi\[
DBUtils.closeConnection(conn); kOAY@a
} UXwB$@8
} Du^x=;
public long getLast(){ UW hn1N
return lastExecuteTime; ,rZn`9
} 5:%..e`T
public void run(){ hqs $yb
long now = System.currentTimeMillis(); sq~+1(X
if ((now - lastExecuteTime) > executeSep) { ESD<8OR
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9p2>`L
//System.out.print(" now:"+now+"\n"); 6Lg!Lodu
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Any Zi'
lastExecuteTime=now; ]l=O%Ev
executeUpdate(); eu}Fd@GO
} B;GxfYj
else{ L19MP
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); fW.GNX8
} ,@Fgr(?'`>
} p@/(.uE
} =R&)hlm
//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 }dX/Y/
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类写好了,下面是在JSP中如下调用。 4ZI!,lv*
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<% \E$1lc
CountBean cb=new CountBean(); ,u}<Ws8N
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); OL=ET)Y
CountCache.add(cb); ua`6M
out.print(CountCache.list.size()+"<br>"); l:Dn3Q
CountControl c=new CountControl(); k,,!P""
c.run(); 731h
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out.print(CountCache.list.size()+"<br>"); (0E U3w?]
%>