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: ;8g[y"I
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CountBean.java 4VP$,|a
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/* ONMR2J(
* CountData.java s&M#]8x;x
* #&snl
* Created on 2007年1月1日, 下午4:44 M3s:B& /
* z_%}F':
* To change this template, choose Tools | Options and locate the template under #Yx
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* the Source Creation and Management node. Right-click the template and choose -IS$1
* Open. You can then make changes to the template in the Source Editor. rw%OA4>
*/ '5\?l:z
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package com.tot.count; ;aDYw [
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/** mV.26D<c
* \RmU6(;IQ
* @author &W%fsy<
*/ y$+_9VzYB
public class CountBean { ~;@\9oPpz%
private String countType; yAQ)/u[|
int countId; G$t:#2
/** Creates a new instance of CountData */ z'}z4^35,
public CountBean() {} @+hO,WXN
public void setCountType(String countTypes){ ]u47]L#
this.countType=countTypes; &/$3>MD2`
} .NMZHK?%
public void setCountId(int countIds){ /;WFRp.
this.countId=countIds; $?y\3GX
} H(DI /"N
public String getCountType(){ gH/(4h
return countType; <*z9:jzQ
} e?<$H\
public int getCountId(){ &XB1=b5
return countId; {CQI*\O
} lh-zE5;
} nQ;M@k&9eV
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CountCache.java R:U!HE8j
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/* Lv@'v4.({
* CountCache.java y-_IMu.J`
* 4YA1~7R
* Created on 2007年1月1日, 下午5:01 B:fulgh2ni
* K}QZdN']
* To change this template, choose Tools | Options and locate the template under i([|@Y=
* the Source Creation and Management node. Right-click the template and choose %8lWJwb7u
* Open. You can then make changes to the template in the Source Editor. |z`AIScT
*/ i}~U/.P
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package com.tot.count;
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import java.util.*; ?zK\!r{
/** Z@bKYfGM
* `86})xz{
* @author A[H"(E#k
*/ @VnK/5opS
public class CountCache { y|(?>\jBl
public static LinkedList list=new LinkedList(); z`!f'I--!
/** Creates a new instance of CountCache */ )OZ
public CountCache() {} w%~Mg3|
public static void add(CountBean cb){ O7yIFqI=/
if(cb!=null){ in2m/q?
list.add(cb); jR"ACup(
} <1E5[9
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} Z8o8>C\d9/
} 8i^d*:R
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CountControl.java 4d%QJ7y
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/* c
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* CountThread.java 5
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* +krDmU9(
* Created on 2007年1月1日, 下午4:57 [ N0"mE<
* IhXP~C6
* To change this template, choose Tools | Options and locate the template under )odz/\9n3c
* the Source Creation and Management node. Right-click the template and choose |\N))K-2D
* Open. You can then make changes to the template in the Source Editor. du&9mOrr
*/ 6,(S}x
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package com.tot.count; K*N8Vpz(
import tot.db.DBUtils; 838@jip
import java.sql.*; 3PEW0b*]Pf
/** ]EEac
* &J,&>CFc
* @author p;)@R$*
*/ 9%DLdc\z;
public class CountControl{ *u!l"0'\
private static long lastExecuteTime=0;//上次更新时间 =/bC0bb{i
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 &+df@U6i
/** Creates a new instance of CountThread */ m,r>E%;Cj
public CountControl() {} Q;=3vUN
public synchronized void executeUpdate(){ te&p1F
Connection conn=null; ?e[]UO
PreparedStatement ps=null; J:0`*7
try{ U8 n=Ro
conn = DBUtils.getConnection(); Ns.{$'ll
conn.setAutoCommit(false); h`:B8+k
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); c4M]q4]F
for(int i=0;i<CountCache.list.size();i++){ kjj?X|Un
CountBean cb=(CountBean)CountCache.list.getFirst(); <'vtnz
CountCache.list.removeFirst(); **F-#",
ps.setInt(1, cb.getCountId()); I1W~;2cK
ps.executeUpdate();⑴ goc"+K
//ps.addBatch();⑵ NQ,2pM<*-
} 9C| -|mo
//int [] counts = ps.executeBatch();⑶ nOK1Wc%/'
conn.commit(); ^o Q^/v~
}catch(Exception e){ L4{+@T1A[
e.printStackTrace(); F*=}}H/
} finally{ ]9~6lx3/
try{
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if(ps!=null) { o.])5i_HV
ps.clearParameters(); 2Y%E.){
ps.close(); %R?#Y1Tq;
ps=null; L[lS
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} j\2q2_f
}catch(SQLException e){} 9Nu:{_YoP
DBUtils.closeConnection(conn); K<fB]44Y
} 'V}4_3#q
} 9 tIE+RD
public long getLast(){ WP4"$W
return lastExecuteTime; ,pa=OF
} XVYj
X
public void run(){ @O)1Hnm
long now = System.currentTimeMillis(); 8v\^,'@
if ((now - lastExecuteTime) > executeSep) { /qweozW_+
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^'$P[
//System.out.print(" now:"+now+"\n"); nh>lDfJV<
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); )0{ZZ-beG
lastExecuteTime=now; y@\J7 h:
executeUpdate(); 2UEjn>2
} 94L>%{59
else{ ]gmkajCzD
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); }?[a>.]u
} og|~:>FmJo
} o<!tNOH
} ]Yt,|CPe2
//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 N|asr,
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类写好了,下面是在JSP中如下调用。 g
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<% w'<"5F`
CountBean cb=new CountBean(); )OV2CP
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); AP(%m';
CountCache.add(cb); I=&Kn@^
out.print(CountCache.list.size()+"<br>"); 9l}G{u9a
CountControl c=new CountControl(); nrCr9#
c.run(); 2w>yW]
out.print(CountCache.list.size()+"<br>"); YfVZ59l4y6
%>