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: #Mw8^FST
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CountBean.java H7:] ]j1
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/* ]z9=}=If
* CountData.java cExS7~*
* *;*r8[U}q
* Created on 2007年1月1日, 下午4:44 HHsmLo c4
* P";'jVcR
* To change this template, choose Tools | Options and locate the template under 0lR5<^B
* the Source Creation and Management node. Right-click the template and choose s->^=dy
* Open. You can then make changes to the template in the Source Editor. MFk5K
*/ "9e\c;a
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package com.tot.count; c0u^zH<
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/** G'A R`"F
* 0"bcdG<}
* @author b SU~XGPB
*/ =C.$
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public class CountBean { 7Jho}5J
private String countType; ~Jz6O U*z
int countId; [hj6N*4y
/** Creates a new instance of CountData */ z' >_Mc6
public CountBean() {} n6a`;0f[R
public void setCountType(String countTypes){ kW&TJP+5*
this.countType=countTypes; [IhYh<i
} y
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public void setCountId(int countIds){ 9qG6Pb
this.countId=countIds; Jg|XH
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} b1?'gn~
public String getCountType(){ S|`o]?nc>
return countType; dlTt_.
} 9-*uPK]m9
public int getCountId(){ omBoo5e
return countId; s!7y
} k+pr \d ~
} p=}Nn(
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CountCache.java WI-1)1t
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/* :Fvrs(
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* CountCache.java YcpoL@ab
* ;;N9>M?b
* Created on 2007年1月1日, 下午5:01 gSQJJxZ{?
* |8tilOqI
* To change this template, choose Tools | Options and locate the template under hx]?&zT@
* the Source Creation and Management node. Right-click the template and choose N[
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* Open. You can then make changes to the template in the Source Editor. A2jUmK.&
*/ q5)O%l !
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package com.tot.count; PxDh7{
import java.util.*; 81
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/** x+@rg];m
* N5b!.B x-w
* @author 'AH0ww_)n
*/ DN5 7p!z
public class CountCache { o:Sa,
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public static LinkedList list=new LinkedList(); Z@PmM4F@S
/** Creates a new instance of CountCache */ +!.^zp21
public CountCache() {} wEvVL
public static void add(CountBean cb){ ?+}_1x`
if(cb!=null){ 'AS|ZRr/
list.add(cb); ,wAF:7'
} k_nql8H
} E#N|wq
} ZX./P0
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CountControl.java .5ha}=z
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/* 1NA.nw.
* CountThread.java ^ sLdAC
* N U`
* Created on 2007年1月1日, 下午4:57 6gu!bu`~
* CdjI`
* To change this template, choose Tools | Options and locate the template under lchPpm9
* the Source Creation and Management node. Right-click the template and choose m`^q <sj
* Open. You can then make changes to the template in the Source Editor. A*547=M/(j
*/ Vb]=B~ ^`
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package com.tot.count; 57']#j#"hj
import tot.db.DBUtils; ;,:`1UI
import java.sql.*; +*/Zu`kzX
/** z/@slT
* 9Y_HyOZ*GX
* @author A@{PZ
*/ PP33i@G
public class CountControl{ @YTaSz$L
private static long lastExecuteTime=0;//上次更新时间 9 X`Sm}i
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 a'yK~;+_9
/** Creates a new instance of CountThread */ SbrecZ
public CountControl() {} )W
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public synchronized void executeUpdate(){ x\G'kEd
Connection conn=null; o9yJf#-En
PreparedStatement ps=null; dn$!&
try{ z/2//mM
conn = DBUtils.getConnection(); DAr1C+Dy
conn.setAutoCommit(false); '$]97b7G
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >$/>#e~
for(int i=0;i<CountCache.list.size();i++){ O) n~](sC\
CountBean cb=(CountBean)CountCache.list.getFirst(); 9gK`E
CountCache.list.removeFirst(); y(yHt=r
ps.setInt(1, cb.getCountId()); HJ[c M6$2
ps.executeUpdate();⑴ $1L>)S
//ps.addBatch();⑵ 9w"4K.
} 1JG'%8}#8
//int [] counts = ps.executeBatch();⑶ L2i_X@/
conn.commit(); O^duZ*b
}catch(Exception e){ e)?
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e.printStackTrace(); =|y9UlsD
} finally{ ,Ae6/D$h/
try{ h_,i&d@(
if(ps!=null) { j@3Q;F0ba
ps.clearParameters(); q\4Xs$APq
ps.close(); 9W1YW9rL
ps=null; ~H<6gN<j(.
} z3m85F%dR
}catch(SQLException e){} \\H}`0m:
DBUtils.closeConnection(conn); '"/=f\)u
} !6O(-S2A
} ,pQZ@I\z
public long getLast(){ ;)z:fToh
return lastExecuteTime; bSi%2Onj
} BLf>_bUk
public void run(){ DGn;m\B
long now = System.currentTimeMillis(); h-K_Lr]
if ((now - lastExecuteTime) > executeSep) { =M[bnq*\
//System.out.print("lastExecuteTime:"+lastExecuteTime); lc1(t:"[
//System.out.print(" now:"+now+"\n"); jTtu0Q|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); .*S#aq4S
lastExecuteTime=now; b;W3j
executeUpdate(); &4x}ppX
} UapC"XYJ
else{ aU "8{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); li'YDtMKCY
} JWhdMU
} RVA(Q[ ;
} Val|n*%
//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 :W.(S6O(
p\tm:QWD;
类写好了,下面是在JSP中如下调用。
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<% S\YTX%Xm}
CountBean cb=new CountBean(); y@: h4u"3
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0oZ=
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CountCache.add(cb); O1U= X:Zl
out.print(CountCache.list.size()+"<br>"); oAJM]%g{
CountControl c=new CountControl(); [")o.(
c.run(); BB!THj69a6
out.print(CountCache.list.size()+"<br>"); j<99FW"@e
%>