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: lcgG5/82
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CountBean.java zQ<;3+*
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/* 7AWq3i{
* CountData.java $Sa7N%D
* pS}IU{#;
* Created on 2007年1月1日, 下午4:44 gGx(mX._L?
* 0,Ib74N'w
* To change this template, choose Tools | Options and locate the template under aAG']y
* the Source Creation and Management node. Right-click the template and choose ]yL+lv
* Open. You can then make changes to the template in the Source Editor. lP*=4Jh
*/ e4tC[6 ;
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package com.tot.count; $)BPtGMGo
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/** 1eEML"
* LZ.Xcy
* @author u0G
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*/ ^S?f"''y3
public class CountBean { dUl"w`3
private String countType; g j]8/~lr
int countId; @+Sr~:K
/** Creates a new instance of CountData */ Fq5u%S
public CountBean() {} T?6<1nU)
public void setCountType(String countTypes){ V\opC6*L_e
this.countType=countTypes; <r`;$K
}
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public void setCountId(int countIds){ AXSip
this.countId=countIds; x(R;xB
} OLm@-I*
public String getCountType(){ .Dl ?a>I
return countType; '}B"071)<
} kWy@wPqms
public int getCountId(){ o0S8ki
return countId; yNn=r;FZQ
} BHYguS^qz
} :FtV~^Z
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CountCache.java jYFmL_{
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/* Xw<;)m
* CountCache.java ?Tu=-ppw
* &}7R\co3
* Created on 2007年1月1日, 下午5:01 /x$JY\cq`
* Dq$1
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* To change this template, choose Tools | Options and locate the template under ->.9[|lIg
* the Source Creation and Management node. Right-click the template and choose q5-i=lw
* Open. You can then make changes to the template in the Source Editor. wVnmT94
*/ F;h^o !W7r
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package com.tot.count; z=g!mVK5
import java.util.*; yRl
/** -PGxG 8S
* [u2t1^#Ol
* @author !K}W.yv,
*/ .Y?]r6CC/
public class CountCache { Y)1J8kq_
public static LinkedList list=new LinkedList(); 3W_7xLA
/** Creates a new instance of CountCache */ ~9vK6;0
public CountCache() {} ]4c+{
public static void add(CountBean cb){ ha=2isq
if(cb!=null){ .r6x9t
list.add(cb); ~n%Lo3RiP
} J`GL_@$q
} &Mudu/KTr
} L3xN#W;m7
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CountControl.java n5.sx|bI?
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/* ,zHL8SiTX
* CountThread.java Bl8|`R^g
* _80L/92
* Created on 2007年1月1日, 下午4:57 5 m-/N?c
* ~S;-sxoO0l
* To change this template, choose Tools | Options and locate the template under 0!0e$!8l
* the Source Creation and Management node. Right-click the template and choose .IdbaH
_a
* Open. You can then make changes to the template in the Source Editor. 2sk7E'2(
*/ EC[]L'IL
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package com.tot.count; j8[U}~*^
import tot.db.DBUtils; la-:"gKC
import java.sql.*; GU2TQx{V
/** sRT H_]c
* Komdz/g
* @author Aixe?A_x
*/ NFEr ,n
public class CountControl{ iz`>'wpC
private static long lastExecuteTime=0;//上次更新时间 hB.8\-}QMq
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #\m.3!Hcr
/** Creates a new instance of CountThread */ @!!u>1
public CountControl() {} 2672oFD
public synchronized void executeUpdate(){ n~|?)EL
Connection conn=null; 2 A!*8w
PreparedStatement ps=null; ;NdH]a{
try{ xp95KxHHo
conn = DBUtils.getConnection(); S!=R\_{u$
conn.setAutoCommit(false); 5=
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Y8v[kuo7
for(int i=0;i<CountCache.list.size();i++){ xlwf @XW
CountBean cb=(CountBean)CountCache.list.getFirst(); T:{r*zLSN
CountCache.list.removeFirst(); F9K0
ps.setInt(1, cb.getCountId()); (P-^ PNz&
ps.executeUpdate();⑴ PLs`Ci|`
//ps.addBatch();⑵ tR'RB@kJ
} 7R:Ij[dV
//int [] counts = ps.executeBatch();⑶ a<r,LE
conn.commit(); ez[x8M>
}catch(Exception e){ {._'Q[
e.printStackTrace(); {Oy|c
} finally{ "%^_.Db>|
try{
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if(ps!=null) { 6#CswSpS
ps.clearParameters(); J.4U;A5
ps.close(); ]9/A=p?J@
ps=null; }l$zZ>.\H
} r.#r!.6 q
}catch(SQLException e){} r1%{\<
DBUtils.closeConnection(conn); %?gG-R
} a"U3h[;$y
} !fn%Q'S
public long getLast(){ H<i!C|AF
return lastExecuteTime; fTy:Re
} l5H5!$3~
public void run(){ +)q ,4+K%}
long now = System.currentTimeMillis(); 8Z\q)T
if ((now - lastExecuteTime) > executeSep) { c8uw_6#r(D
//System.out.print("lastExecuteTime:"+lastExecuteTime); *,lDo9
//System.out.print(" now:"+now+"\n"); :g63*d+/G
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); CA`V)XIsP
lastExecuteTime=now; }O@>:?U
executeUpdate(); GyQFR ?
} &>+T*-'
else{ Q?>r:vMi
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); hui
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} n)q8y0if
} 0:[A4S`X
} 0/f|ZH ~!
//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 ,(x`zpp _
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类写好了,下面是在JSP中如下调用。 $#D#ezvxe
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<% mp$IhJ6#
CountBean cb=new CountBean(); `Pj7:[."[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); er3~gm
CountCache.add(cb); v0 :n:q
out.print(CountCache.list.size()+"<br>"); A9BoH[is7
CountControl c=new CountControl(); -Z,r\9d
c.run(); `Ze$Bd\
out.print(CountCache.list.size()+"<br>"); UG`~RO
%>