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: t+Qx-sW
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CountBean.java | tFg9RT
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/* Ece=loV*l
* CountData.java "Q[?W(SA
* ;F/w&u.n
* Created on 2007年1月1日, 下午4:44 }l5Q0'
* ~yY5pnJ
* To change this template, choose Tools | Options and locate the template under {w v{"*Q9Q
* the Source Creation and Management node. Right-click the template and choose i~{ 0>"9
* Open. You can then make changes to the template in the Source Editor. 85:mh\@-G
*/ -Y>QKS
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package com.tot.count; #*"I?B/fd8
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/** K/!>[d
* 3AcDW6x|
* @author EB
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*/ 2=n,{rkmj%
public class CountBean { $N4i)>&T2
private String countType; 75c\.=G9q<
int countId; TTSq }sb}
/** Creates a new instance of CountData */ Ge*N%=MX8
public CountBean() {} [qxDCuxq
public void setCountType(String countTypes){ y# IUDnRJ
this.countType=countTypes; 6PMu*-Nv!j
} ca:Vdrw`
public void setCountId(int countIds){ z2;<i|Ez0
this.countId=countIds; jq(rnbV
} ~AcjB(
public String getCountType(){ D!V*H?;U
return countType; S\@U3|Q5
} X D\;|
public int getCountId(){ "iuNYM5P
return countId; HQc^ybX5
} `OWwqLoeA
} )yS S 2
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CountCache.java 0w6"p>s>c
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/* |1m2h]];Q
* CountCache.java \*30E<;C_
* xp]_>WGq
* Created on 2007年1月1日, 下午5:01 B~u`bn,iQ
* o^x,JT
* To change this template, choose Tools | Options and locate the template under "X-"uIc
* the Source Creation and Management node. Right-click the template and choose 2nI^fVR%\
* Open. You can then make changes to the template in the Source Editor. uh3<%9#\k
*/ H `_{n<
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package com.tot.count; L ?S#3@Pa
import java.util.*; -'j|U[&N\
/** *,Sa*-7(
* 8q|T`ac+N
* @author )fbYP@9>a
*/ %}Z1KiRiX
public class CountCache { |N5|B Q(y$
public static LinkedList list=new LinkedList(); g` 41d
/** Creates a new instance of CountCache */ b5l;bXp]
public CountCache() {} <1kK@m -E
public static void add(CountBean cb){ I=7 YAm[W
if(cb!=null){ Q\z9\mMG-
list.add(cb); F?4&qbdD
} i5czm?x
} "lKR~Qi
} f<Yg_ TG
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CountControl.java :\|<7n
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/* <p#+('N`
* CountThread.java ]J.|XRp/
* B{7hRk.5!
* Created on 2007年1月1日, 下午4:57 W>E|Iv[o
* %"AB\lL.
* To change this template, choose Tools | Options and locate the template under :Gf
* the Source Creation and Management node. Right-click the template and choose Uq(fk9`6
* Open. You can then make changes to the template in the Source Editor. TL: 6Pe
*/ R(GL{Dh}L
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package com.tot.count; \C"hL(4-
import tot.db.DBUtils; BB? 4>#D
import java.sql.*; jR^_1bu
/** 1-8G2e
* US]I[Y6V
* @author yzyK$WN\[3
*/ -~^sSLrbP
public class CountControl{ g<YN#
private static long lastExecuteTime=0;//上次更新时间 Jmun^Q/h
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 8g3?@i
/** Creates a new instance of CountThread */ 1W{t?1[s
public CountControl() {} R-1C#R[
public synchronized void executeUpdate(){ +y|Q7+
Connection conn=null; > |(L3UA9
PreparedStatement ps=null; 'E4}++\
try{ e^or qw/I
conn = DBUtils.getConnection(); oN=>U"<\1
conn.setAutoCommit(false); bA/'IF+
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Z4D[nPm$
for(int i=0;i<CountCache.list.size();i++){ 6Vu)
CountBean cb=(CountBean)CountCache.list.getFirst(); rWip[>^
CountCache.list.removeFirst(); B[;aNyd<
ps.setInt(1, cb.getCountId()); }k_'a^;C1
ps.executeUpdate();⑴ !5>PZ{J
//ps.addBatch();⑵ %G'P!xQhy
} VH<-||X/4
//int [] counts = ps.executeBatch();⑶ .c\iKc#
conn.commit(); *Jg&:(#}<J
}catch(Exception e){ uS5ADh
e.printStackTrace(); '_FxxLAO
} finally{ r|Q/:UV?w
try{ `5 MK(K
:
if(ps!=null) { 6sNw#pqh
ps.clearParameters(); p4z
thdN[
ps.close(); D[3QQT7c
ps=null; &Yd6w}8
} SX[
}catch(SQLException e){} h|OWtf4
DBUtils.closeConnection(conn); `"y:/F"{
} @$5=4HA
} {EyWSf"
public long getLast(){ ?I;PJj
return lastExecuteTime; mIv}%hD
} &|fWtl;43
public void run(){ 1i@a? 27|
long now = System.currentTimeMillis(); #F'8vf'r
if ((now - lastExecuteTime) > executeSep) { Wn Ng3'6
//System.out.print("lastExecuteTime:"+lastExecuteTime); =!DpW VsQ
//System.out.print(" now:"+now+"\n"); -BEd7@?A
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); yhd]s0(!
lastExecuteTime=now; U i`#B
executeUpdate(); >lF@M-
} ricL.[v9S
else{ !twYjOryH[
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); N;i\.oY
} /NQ
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} t/h,-x
} UZJ#/x5F
//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 +3]V>Mv
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类写好了,下面是在JSP中如下调用。 D|IS@gWa
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<% Pdk#"H-j
CountBean cb=new CountBean(); q5\iQ2f{WV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); #E#Fk3-ljQ
CountCache.add(cb); Nu@dMG<5
out.print(CountCache.list.size()+"<br>"); |
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CountControl c=new CountControl(); >YR2h/S
c.run(); d^d+8R
out.print(CountCache.list.size()+"<br>"); M# cJ&+rP
%>