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: i|! 9o:
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CountBean.java pU)3*9?cIl
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/* H_nOE(i<z
* CountData.java tS.b5$Q
* SoON@h/
* Created on 2007年1月1日, 下午4:44 whp\*]8
* ,EJ [I^
* To change this template, choose Tools | Options and locate the template under ~a0}
* the Source Creation and Management node. Right-click the template and choose !5
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* Open. You can then make changes to the template in the Source Editor. #Ew
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*/ ?ia[KLt"
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package com.tot.count; Jj _+YfIM
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{
/** [Kj#KJxy
* 0$dNrq
* @author `0gK;D8t
*/ dCJR,},\f
public class CountBean { O%h
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private String countType; dZ81\jdYv
int countId; yA )+-
/** Creates a new instance of CountData */ ^
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public CountBean() {} MicVNs
public void setCountType(String countTypes){ u KdX4
this.countType=countTypes; ?g1.-'
} N`GwL
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public void setCountId(int countIds){ o2UJ*4
this.countId=countIds; 4!RI2?4V
} vM;dPE7
public String getCountType(){ J_br%AG<p
return countType; -`1L[-<d=/
} Dve5m=
public int getCountId(){ p:n^c5
return countId; RloPP
} ~G^doj3|+
} Z8_gI[Zn
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CountCache.java Tk=3"y+u[
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/* uWT&`m_(2
* CountCache.java Uwil*Jh
* 6_
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* Created on 2007年1月1日, 下午5:01 y:Ab5/bHy
* E|#R0n*
* To change this template, choose Tools | Options and locate the template under !d@`r1t
* the Source Creation and Management node. Right-click the template and choose {Ag}P0%'
* Open. You can then make changes to the template in the Source Editor. 'aWZ#GS*
*/ `lOoT
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package com.tot.count; h>Pg:*N,(
import java.util.*; j %0_!*#3
/** eBKIdR%k
* FDC{8e
* @author ;;H:$lx
*/ 4}FfHgpQ
public class CountCache { #I wB
public static LinkedList list=new LinkedList(); 2=
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/** Creates a new instance of CountCache */ wLSYzz
public CountCache() {} -+Dvyr
public static void add(CountBean cb){ + # >%bq x
if(cb!=null){ a[rUU'8
list.add(cb); <LZvh8
} `3n*4Lz
} 1"6k5wrIA
} 8dB~09Z7
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CountControl.java K0@7/*%
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/* Q^Z}Y~.
* CountThread.java .AW*7Pp`f
* .e+UgCwi
* Created on 2007年1月1日, 下午4:57 WcG&W>
* N^N?!I
* To change this template, choose Tools | Options and locate the template under 3dphS ^X
* the Source Creation and Management node. Right-click the template and choose ~` hcgCi%
* Open. You can then make changes to the template in the Source Editor. C^tC} n1D(
*/ g_X7@Dt
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package com.tot.count; ijYLf.R<
import tot.db.DBUtils; [DEw:%
import java.sql.*; N|LVLsK
/** N9<eU!4>
* z\5Nni/~6D
* @author Q[KR,k
*/ <`q o*__1
public class CountControl{ 9U*vnLB
private static long lastExecuteTime=0;//上次更新时间 M(jH"u&f
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 RJ44o>L4O
/** Creates a new instance of CountThread */ }6N|+z.cU
public CountControl() {} 6u}NI!he
public synchronized void executeUpdate(){ I SmnZ@
Connection conn=null; i=+6R
PreparedStatement ps=null; 2ZeL
try{ 5?MvO]_
conn = DBUtils.getConnection(); |_*1/Wz@
conn.setAutoCommit(false); -y(V-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); w>s
for(int i=0;i<CountCache.list.size();i++){ .Ps;O
CountBean cb=(CountBean)CountCache.list.getFirst(); tPHiz%
CountCache.list.removeFirst(); 8=9sIK2
ps.setInt(1, cb.getCountId()); )^+$5OR\c
ps.executeUpdate();⑴ NM Ajt>t
//ps.addBatch();⑵ KK?~i[aL
}
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//int [] counts = ps.executeBatch();⑶ Gov{jksr
conn.commit(); IM/\t!*7
}catch(Exception e){ 6dUP's_
e.printStackTrace(); =Yk$Q\c
} finally{ j@2 hI,+
try{ `39U I7
if(ps!=null) { Y# #J
ps.clearParameters(); o<4LL7$A!
ps.close(); V2.K*CpZ7
ps=null; RFdN13sJv
} 9[*kpMC
}catch(SQLException e){} z4goa2@Z
DBUtils.closeConnection(conn); 2H#vA
}
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} "$&F]0
public long getLast(){ o6R(BMwGa
return lastExecuteTime; Mi/_hzZ\
} wF(FV4#gs
public void run(){ ZU|nKt<GK
long now = System.currentTimeMillis(); Fk43sqU6~
if ((now - lastExecuteTime) > executeSep) { itU01
//System.out.print("lastExecuteTime:"+lastExecuteTime); e_TM#J(3
//System.out.print(" now:"+now+"\n"); @b
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); aZRgd^4
lastExecuteTime=now; i/L1KiCLx
executeUpdate(); \Mi< ROp5
} u+9Mc u"
else{ mR^D55k
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); i@RjG
} <3bh-)
} tv2dyC&a
} {e^llfj$#
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 b<8h\fR#'
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类写好了,下面是在JSP中如下调用。 KK+Mxoj,
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<% 4*3vZ6lhu
CountBean cb=new CountBean(); oOlI*/OMb
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ,y.0Cb0
CountCache.add(cb); -4]6tt'G
out.print(CountCache.list.size()+"<br>"); dw-r}Qioe
CountControl c=new CountControl(); w-2]69$k
c.run(); 4u&doSXR
out.print(CountCache.list.size()+"<br>"); ;@L#0
%>