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: ?@R")$
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CountBean.java !EF(*~r!9L
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/* >0Ev#cX4
* CountData.java 'GJVWpvUU
* M R'o{?{e`
* Created on 2007年1月1日, 下午4:44 n&-496H
* *~z#.63oZ
* To change this template, choose Tools | Options and locate the template under DB`QsiC)
* the Source Creation and Management node. Right-click the template and choose zzZg$9PT[
* Open. You can then make changes to the template in the Source Editor. ]M,06P>?
*/ wk\L* \@Y}
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package com.tot.count; kGN||h
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/** LD (C\
* V/"}ku
* @author /&Jv,[2kV
*/ 7\/5r.
public class CountBean { 4p) e}W*
private String countType; beZ(o?uK
int countId; UQd6/mD`e
/** Creates a new instance of CountData */ O.k\]'
public CountBean() {} zuL7%qyv
public void setCountType(String countTypes){ 0y%L-:/c|
this.countType=countTypes; *]s&8/Gmb
} ';RI7)<
public void setCountId(int countIds){ x:5dCI
this.countId=countIds;
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} . p^xS6e{
public String getCountType(){ A8?[6^%O|
return countType; ^uaFg`S
} 0,FC
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public int getCountId(){ Ie'P#e'
return countId; X;fy\HaU
} 45}v^|Je\
} @qK<T
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CountCache.java b; 9n'UX\
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/* O|v
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* CountCache.java J\W-dI
* K]N~~*`%`
* Created on 2007年1月1日, 下午5:01 P#G.lft"O
* cfoYnM
* To change this template, choose Tools | Options and locate the template under B}*V%}:)
* the Source Creation and Management node. Right-click the template and choose -G ?%QG`v
* Open. You can then make changes to the template in the Source Editor. @R:#"
*/ f\ "`7
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package com.tot.count; C?H{CP
import java.util.*; V,QwN&
/** WOndE=(V
* RfbdBsL
* @author z] @W[MHY
*/ ]b[,LwB\`~
public class CountCache { rm+v(&
public static LinkedList list=new LinkedList(); 85>S"%_
/** Creates a new instance of CountCache */ p$!@I
public CountCache() {} B.-A $/
public static void add(CountBean cb){ 2mJ:c
if(cb!=null){ c %<2z
list.add(cb); IUhp;iH
} Ao`_",E
} b>q6:=((
} 6S*zzJ.0K
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CountControl.java LZ&uj{ <
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/*
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* CountThread.java -qn[HXq
* ~%aJFs
* Created on 2007年1月1日, 下午4:57 q]v,
* c2b6B.4
* To change this template, choose Tools | Options and locate the template under _:,.yRez
* the Source Creation and Management node. Right-click the template and choose mrnxI#6
* Open. You can then make changes to the template in the Source Editor. +Hy4s[_|
*/ ATO
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package com.tot.count; Ff/Ig]Lb
import tot.db.DBUtils; x*mc - &N
import java.sql.*; )y\BY8
/** ib50LCm
* 3}M\c)
* @author 5!:._TcO
*/ 75(W(V(q
public class CountControl{ @f=RL)$|
private static long lastExecuteTime=0;//上次更新时间 M]0^ind
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 nL;K|W
/** Creates a new instance of CountThread */ QV)}3pW
public CountControl() {} Gm@iV,F%R
public synchronized void executeUpdate(){ FuMq|S
Connection conn=null; r
}
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PreparedStatement ps=null; Hs<n^fyf
try{ e 2*F;.)
conn = DBUtils.getConnection(); `V~LV<v5
conn.setAutoCommit(false); ^?Vq L\V5
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;l`X!3
for(int i=0;i<CountCache.list.size();i++){ lQr6;D}+
CountBean cb=(CountBean)CountCache.list.getFirst(); ;E2kT
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CountCache.list.removeFirst(); XZBj=2~-3
ps.setInt(1, cb.getCountId()); j&llrN
ps.executeUpdate();⑴ c9|a$^I6
//ps.addBatch();⑵ vcOsq#UW
} ho|8U
//int [] counts = ps.executeBatch();⑶ '^lUL) R
conn.commit(); 8DL hk
}catch(Exception e){ {fElto
e.printStackTrace(); tBTJmih"
} finally{ x#o?>5Qg?
try{ ;E2~L
if(ps!=null) { 49y*xMn
ps.clearParameters(); 7BrV<)ih{*
ps.close(); 5\+EHW!o
ps=null; G*Ib^;$u
} 8v$g
}catch(SQLException e){} X o_] v
DBUtils.closeConnection(conn); ;:^ Lv
} 1bDJ}M~]z
} 6#?NL]A
public long getLast(){
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return lastExecuteTime; Ix4 jof6(
} sVlZNj9i"
public void run(){ )1BiEK`v
long now = System.currentTimeMillis(); As p8qHS
if ((now - lastExecuteTime) > executeSep) { J{^n=X9M0J
//System.out.print("lastExecuteTime:"+lastExecuteTime); q1<Fg.-r
//System.out.print(" now:"+now+"\n"); rN'.&;Y5
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 7zi"caY
lastExecuteTime=now; -Cml0}.O
executeUpdate(); ]#M/$?!]g2
} H&u4v2
else{ w1.MhA
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); afV
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} w+3>DEfz
} u,!4vKx
} ?bn;{c;E
//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 CElPU`J,\[
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类写好了,下面是在JSP中如下调用。 3P3:F2S R
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<% bA0uGLc
CountBean cb=new CountBean(); xan/ay>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); &,_?>.\[<
CountCache.add(cb); qU}lGf!dVn
out.print(CountCache.list.size()+"<br>"); U"/yB8!W
CountControl c=new CountControl(); ,?t}NZY&
c.run(); 1riBvBT
out.print(CountCache.list.size()+"<br>"); ;4R=eI
%>