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: f=g/_R2$xN
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CountBean.java b!<?,S
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/* |UBR8
* CountData.java vr=iG
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* C4TJS,!1rH
* Created on 2007年1月1日, 下午4:44 5pE[}@-c9
* &tHT6,Xv(
* To change this template, choose Tools | Options and locate the template under y{U'\
* the Source Creation and Management node. Right-click the template and choose qmtVk
* Open. You can then make changes to the template in the Source Editor. ^\{%(i9
*/ r3_@ L>;
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package com.tot.count; _"##p
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/** W&TPrB
* L7%Dc2{^(
* @author }g5h"N\$o
*/ tiI>iP`!
public class CountBean { z#8GF^U:T
private String countType; ^HX={(ddK
int countId; -:*PXu
/** Creates a new instance of CountData */ kIP~XV~
public CountBean() {} Yf7n0Etd,
public void setCountType(String countTypes){ 86vk"
this.countType=countTypes; bX=ht^e[
} gO gZ
public void setCountId(int countIds){ r-H~MisL
this.countId=countIds; 3yZtyXRPn
} %:YON,1b=7
public String getCountType(){ LN" bGe
return countType; ov*zQP
} V.: a6>]
public int getCountId(){ !94&Uk(O
return countId; }i|o":-x+
} KFCuv15w,3
} D0us<9q
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CountCache.java EYcvD^!1g
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/* J &u&G7#S
* CountCache.java *{)[:;
* C W7E2
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* Created on 2007年1月1日, 下午5:01 k2j:s}RHY
* C>:F4"0
* To change this template, choose Tools | Options and locate the template under vXq=f:y4
* the Source Creation and Management node. Right-click the template and choose Xi4!7IOmo
* Open. You can then make changes to the template in the Source Editor. G5kM0vs6L
*/ `P)1RTVx
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package com.tot.count; D7 [n^WtL
import java.util.*; gmj
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/** 4ME8NEE
* X>wB=z5PXK
* @author G>YJ3p7
*/ )[~ #j6
public class CountCache { fP&F$"o8
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ gD@ &/j7
public CountCache() {} iL/(WAB_od
public static void add(CountBean cb){ Ty*ec%U9F
if(cb!=null){ % 95:yyH 0
list.add(cb); TEh]-x`
} ie
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} 6IctW5b
} oZA|IF8U0
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CountControl.java Q2Yv8q_}Uq
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/* K.*?\)&
* CountThread.java )gmDxD
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* C$"jZcm,I
* Created on 2007年1月1日, 下午4:57 rPaD#GA[7
* f`:e#x
* To change this template, choose Tools | Options and locate the template under ,b-wo
* the Source Creation and Management node. Right-click the template and choose -E2[PW4$
* Open. You can then make changes to the template in the Source Editor.
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*/ bv\V>s
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package com.tot.count; i\3BA"ZX
import tot.db.DBUtils; r[TS#hQ
import java.sql.*; ~XsS00TL`G
/** $a15
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* !V+5$TsS
* @author U"%k4]:A
*/ C:
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public class CountControl{ >u*woNw(XM
private static long lastExecuteTime=0;//上次更新时间 hX`WVVoF
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6N~ jt
/** Creates a new instance of CountThread */ Kp~k!6x
public CountControl() {} D8m?`^Zz
public synchronized void executeUpdate(){ /v5Pk.!o
Connection conn=null; 7/PHg)&
PreparedStatement ps=null; +A~lPXAXW
try{ g#9w5Q
conn = DBUtils.getConnection(); XhWMvme
conn.setAutoCommit(false); sx*1D9s_
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); P^rSpS9
for(int i=0;i<CountCache.list.size();i++){ AN^ ,
CountBean cb=(CountBean)CountCache.list.getFirst(); k5!k3yI
CountCache.list.removeFirst(); 4TwU0N+>
ps.setInt(1, cb.getCountId()); 7 aDI6G
ps.executeUpdate();⑴ +}m j6I
//ps.addBatch();⑵ "{z9 L+
} II>X6
//int [] counts = ps.executeBatch();⑶ m9#u.Q*
conn.commit(); R#Bt!RNZ
}catch(Exception e){ PO&xi9_
e.printStackTrace(); oYJ&BPuA'
} finally{ *ivbk /8
try{ ]3d&S5zU
if(ps!=null) { (g7nMrE$j
ps.clearParameters(); hXz"}X n
ps.close(); }[LK/@h
ps=null; }{K)5k@
} L'aMXNO
}catch(SQLException e){} v|{*y
DBUtils.closeConnection(conn); )&_{m
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} pM(y?zGt
} {E 6W]Mno
public long getLast(){ /jj@ =H
return lastExecuteTime; Q96g7[
} e% 5!
public void run(){ *,'"\n
long now = System.currentTimeMillis(); !Id F6 %
if ((now - lastExecuteTime) > executeSep) { 5~rs55W
//System.out.print("lastExecuteTime:"+lastExecuteTime); gvcT_'
//System.out.print(" now:"+now+"\n"); b]|7{yMV
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); U]R7=
lastExecuteTime=now; l" sR\`~
executeUpdate(); vm4]KEyrX
} r5s*"z
else{ /OxF5bN2
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^'[ |
} JRodYXjE
} X0!48fL*
} A@DIq/^xM
//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 Wq,UxMz
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类写好了,下面是在JSP中如下调用。 ||!k 3t#<
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<% ko,
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CountBean cb=new CountBean(); 4e%SF|(Y'h
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /1OhW>W3eH
CountCache.add(cb); P}VD}lEyO
out.print(CountCache.list.size()+"<br>"); OKf/[hyu
CountControl c=new CountControl(); F'*{Fk
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c.run(); E3gQ`+wNg?
out.print(CountCache.list.size()+"<br>"); l7x%G@1#~W
%>