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: LBK{-(%
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CountBean.java /IUu-/ D
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/* C:J;'[,S
* CountData.java fkzSX8a9}
* 2H|:/y
* Created on 2007年1月1日, 下午4:44 ccuGM W G*
* .c"nDCFVR
* To change this template, choose Tools | Options and locate the template under ^}=)jLS
* the Source Creation and Management node. Right-click the template and choose w==BSH[
* Open. You can then make changes to the template in the Source Editor. .*zS2z
*/ sxREk99lL
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package com.tot.count; o{s2T)2
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/** 5.~Je6K U
* '8X>,un
* @author 1VX3pkUET
*/ ~wb1sn3
public class CountBean { Kq")\Ha,f
private String countType; X(N~tE
int countId; EMmgX*iu@
/** Creates a new instance of CountData */ 7s|'NTp
public CountBean() {} I@'[> t
public void setCountType(String countTypes){ g<:Lcg"u
this.countType=countTypes; JY0aE
} r[L%ap\{
public void setCountId(int countIds){ `>:5[Y
this.countId=countIds; ;}46Uc#WS
} H`JFXMa<
public String getCountType(){ b' o]Y
return countType; t}q
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} Js,! G
public int getCountId(){ ;t&q|}x"
return countId; l76=6Vtb
} n$/|r
} bWswF<y-
)/;KxaKt
CountCache.java Tru{8]uMH
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/* !Z!)$3bB
* CountCache.java Z,).)y#B
* Ma^jy.
* Created on 2007年1月1日, 下午5:01 }T?X6LA$I8
* }Ce9R2
* To change this template, choose Tools | Options and locate the template under gmL~n7m:K
* the Source Creation and Management node. Right-click the template and choose hw
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* Open. You can then make changes to the template in the Source Editor. Vm[Rp,"
*/ cbzA`b'Mg
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package com.tot.count; nh} Xu~#_
import java.util.*; TjW!-s?S
/** OdzeHpH3g
* /%T/@y
* @author |p|Zv H
*/ s.2f'i+
public class CountCache { Nm*(?1
public static LinkedList list=new LinkedList(); ?XBdBR_"^
/** Creates a new instance of CountCache */ -/Q5?0z
public CountCache() {} Qa{5]+E
public static void add(CountBean cb){ VdHT3r
if(cb!=null){ jRK}H*uem
list.add(cb); Y6jyU1>
} 6j%%CWU{~
} %rW}x[M%w?
} 7H6Ts8^S
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CountControl.java yZleots1
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/* m%HT)`>bg
* CountThread.java 3<xE_ \DR
* BhJ>G%
* Created on 2007年1月1日, 下午4:57 VE|:k:};
* p _gN}v
* To change this template, choose Tools | Options and locate the template under _{*} )&!M
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. bfxE}>
*/ 5nG\J
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package com.tot.count; wLV,E,gM
import tot.db.DBUtils; r&u1-%%9[
import java.sql.*; F @PPhzZ
/** PucNu8
* QK-aH1r
* @author C;BO6$*_e
*/ a"#t'\
public class CountControl{ 4)8k?iC*
private static long lastExecuteTime=0;//上次更新时间 @cDB 7w\
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 LRJX>+@
/** Creates a new instance of CountThread */ +:KZEFY?<
public CountControl() {} *6s_7{;
public synchronized void executeUpdate(){ {*_Ln
Connection conn=null; (}A$4?
PreparedStatement ps=null; ,1]UOQ>AP
try{ ` H'G"V
conn = DBUtils.getConnection(); TFSdb\g
conn.setAutoCommit(false); #7uH>\r
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); oC&}lp)q
for(int i=0;i<CountCache.list.size();i++){ omfX2Oa2
CountBean cb=(CountBean)CountCache.list.getFirst(); z|g2Q#$-\S
CountCache.list.removeFirst(); 1iT_mtXK$
ps.setInt(1, cb.getCountId()); TegdB|y7O
ps.executeUpdate();⑴ ndSu-8?L
//ps.addBatch();⑵ E>fY,*0
} nW=6nCyvo
//int [] counts = ps.executeBatch();⑶ x;mw?B[
conn.commit(); 9{pT)(Wnb
}catch(Exception e){ z
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e.printStackTrace(); YD4I2'E
} finally{ a*M|_&MH*
try{ %['NPs%B
if(ps!=null) { WBjJ)vCA.
ps.clearParameters(); N_%@_$3G]
ps.close(); }e7Rpgu
ps=null; Wv4$Lgr
} !r/i<~'Bx
}catch(SQLException e){} %NLd"SV
DBUtils.closeConnection(conn); 2[lP ,;!
} }?m0bM
} rZI63S
public long getLast(){ }9OMXLbRv
return lastExecuteTime; Xu{y5N
} pSx5ume95"
public void run(){ lxn/97rA
long now = System.currentTimeMillis(); "im5Fnu
if ((now - lastExecuteTime) > executeSep) {
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//System.out.print("lastExecuteTime:"+lastExecuteTime); 1j2U,_-
//System.out.print(" now:"+now+"\n"); HNZ$CaJh
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); iM .yen_vp
lastExecuteTime=now; VwR\"8r3
executeUpdate(); $WYt`U;*lj
} ekx(i
QA
else{ [if(B\&
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X}#vt?mu
} G4
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} U]Q5};FK
} tB;PGk_6
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ^gVQ6=z%
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类写好了,下面是在JSP中如下调用。 < F5VJ
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<% wBt7S!>G
CountBean cb=new CountBean(); rfDGS%!O%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |q4=*X q
CountCache.add(cb); g$Tsht(rHD
out.print(CountCache.list.size()+"<br>"); TOiLv.Dor
CountControl c=new CountControl(); qO@vXuul,
c.run(); [n9l[dN
out.print(CountCache.list.size()+"<br>"); fw %p_Cm
%>