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: `-5cQ2>"
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CountBean.java ZG!x$yi$
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/* )e#fj+>x)
* CountData.java TLX^~W[gOm
* 7ia"u+Y
* Created on 2007年1月1日, 下午4:44 ]P
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* I_K[!4~Kn
* To change this template, choose Tools | Options and locate the template under IS .g);Gj
* the Source Creation and Management node. Right-click the template and choose t0+t9w/fTP
* Open. You can then make changes to the template in the Source Editor. 2kC^7ZAwu
*/ [gTQ-
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package com.tot.count; *(>Jd|C
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/** IZ|c<#r6
* dV$3u"9
* @author "C?:T'dW
*/ rkbl/py
public class CountBean { G)jG!`I
private String countType; [6oq##
int countId; xqU^I5Z
/** Creates a new instance of CountData */ -fhAtxkg
public CountBean() {} jDFp31_X
public void setCountType(String countTypes){ QZqpF9Eu
this.countType=countTypes; ZyZl\\8U
} KhLg*EL
public void setCountId(int countIds){ D1"1MUSod
this.countId=countIds; S|s3}]g9
} X"laZd947>
public String getCountType(){ (=6P]~,
return countType; %+/f'6kR
} xAFek;GY?
public int getCountId(){ fYv ;TV>73
return countId; I4A;
} !2/l9SUi
} Cb+P7[X-
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CountCache.java YAX #O\,
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/* (Be$$W
* CountCache.java R
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* |Tj`qJGVw
* Created on 2007年1月1日, 下午5:01 L;L2j&i%v)
* 9Kq<\"7Bmz
* To change this template, choose Tools | Options and locate the template under 2#,8evH
* the Source Creation and Management node. Right-click the template and choose Y=PzN3
* Open. You can then make changes to the template in the Source Editor. oM/B.U2a
*/ kOo>Iy
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package com.tot.count; Q1]V|S;)X
import java.util.*; &;'w8_K"^
/** W,0KBkkp
* 9)8*FahW
* @author hB?U5J
*/ wn&[1gBxM
public class CountCache { kO
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public static LinkedList list=new LinkedList(); H0 {Mlu9
/** Creates a new instance of CountCache */ bWhJ^LD
public CountCache() {} s{b0#[
public static void add(CountBean cb){ >1_Dk7E0D
if(cb!=null){ 2l]C55p)s
list.add(cb); :-W$PIBe
} JDIz28 Ww
} VGq{y{(
} pT|./ Fe
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CountControl.java s0x@
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/* !NlB%cF
* CountThread.java ^!zJf7(+<>
* /DgT1^&0
* Created on 2007年1月1日, 下午4:57 <FMuWHY
* ,C5@P+A
* To change this template, choose Tools | Options and locate the template under "j*fVn
* the Source Creation and Management node. Right-click the template and choose 0Og/47dO.2
* Open. You can then make changes to the template in the Source Editor. G7Edi;y/{
*/ Z&2
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package com.tot.count; UMnR=~.
import tot.db.DBUtils; iPRJA{$b_
import java.sql.*; ]9!Gg
/** <m|FccvQ
* Vs2 v j
* @author krnvFZRTQ
*/ <v1_F;{n
public class CountControl{ EBN]>zz
private static long lastExecuteTime=0;//上次更新时间 BV_a-\Sa=
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #d7)$ub
/** Creates a new instance of CountThread */ A5(kOtgiT
public CountControl() {} SLbavP#G
public synchronized void executeUpdate(){ O&gy(
Connection conn=null; P,s)2 s'nZ
PreparedStatement ps=null; #t5JUi%in*
try{ >d1aE)?
conn = DBUtils.getConnection(); _dH[STT
conn.setAutoCommit(false); |\yDgs%EGy
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); [kU[}FT
for(int i=0;i<CountCache.list.size();i++){ gwkZk-f\p
CountBean cb=(CountBean)CountCache.list.getFirst(); uWM4O@Qn)d
CountCache.list.removeFirst(); g[uE@Gaj&
ps.setInt(1, cb.getCountId()); x_>"Rnv:K
ps.executeUpdate();⑴ see'!CjVo2
//ps.addBatch();⑵ O V0cr
} dNS9<8JX
//int [] counts = ps.executeBatch();⑶ ^@l5u=
conn.commit(); E!O(:/*
}catch(Exception e){ RMs1{64:
e.printStackTrace(); A
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} finally{ T`0`]z !~
try{ Mz%d_
if(ps!=null) { btkMY<o7
ps.clearParameters(); EHE6-^F
ps.close(); *(_ON$+3
ps=null; -h.3M0
} t 's5~
}catch(SQLException e){} /eI,]CB'z
DBUtils.closeConnection(conn); AH ?MJKY@Z
} `zV-1)=
} MXu+I,y*
public long getLast(){ '<U[;H9\
return lastExecuteTime; !E(J
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} $[L)f|
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public void run(){ =r@ie>*U
long now = System.currentTimeMillis(); {BwN4r46
if ((now - lastExecuteTime) > executeSep) { :;#c:RKi:
//System.out.print("lastExecuteTime:"+lastExecuteTime); ' ]H#0.
//System.out.print(" now:"+now+"\n"); +LU ).
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1dXO3hot
lastExecuteTime=now; ;_;H(%uY
executeUpdate(); NEjBjLJZ
} j2C^1:s@m
else{ ^{:[^$f:l
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); s^x ,S
} <jg
wdbT"6
} jAK`96+D~b
} +&@l{x(,
//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 RM/ s:
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类写好了,下面是在JSP中如下调用。 jDkc~Wwa
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<% 3k|~tVM
CountBean cb=new CountBean(); PhaQ3%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); LVz%$Cq,0
CountCache.add(cb); }9fV[zO
out.print(CountCache.list.size()+"<br>"); !15@M|,OL
CountControl c=new CountControl(); !IrKou)/_
c.run(); 5juCeG+Z
out.print(CountCache.list.size()+"<br>"); Kk"B501
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