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: " &2Kvsz
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CountBean.java KZoIjK]
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/* zOJ4I^^
* CountData.java R-8>,
* \]RPxM:_>
* Created on 2007年1月1日, 下午4:44 6;s.%W
* buV{O[
* To change this template, choose Tools | Options and locate the template under pQv`fr=
* the Source Creation and Management node. Right-click the template and choose T
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* Open. You can then make changes to the template in the Source Editor. k4:$LFw@
*/ K|JpkEw
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package com.tot.count; dqF]kP,VG
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/** )e&U'Fx
* /)RyRS8c
* @author ILi{5L
*/ FW* k O
public class CountBean { =rSJ6'2("
private String countType; 8@;|x2=y
int countId; 5cj]Y)I-~
/** Creates a new instance of CountData */ B(tLV9B3Q
public CountBean() {} C\"nlNKw
public void setCountType(String countTypes){ )F_vWbg
this.countType=countTypes; cGF_|1`
} wEd+Ds]$
public void setCountId(int countIds){ g7\MFertR^
this.countId=countIds; s
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} 0"l*8%g
public String getCountType(){ *}fs@"S
return countType; bY`
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} ^a+W!
public int getCountId(){ GD(gm,,)
return countId; z
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} {Hc [H-
} \Af25Mcf:
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CountCache.java >ZRCM
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/* >O0z+tj
* CountCache.java J)R2O{ z
* _(A9k{
* Created on 2007年1月1日, 下午5:01 2;8I0BH*'
* [l~Gwaul>
* To change this template, choose Tools | Options and locate the template under ;MSdTHN"
* the Source Creation and Management node. Right-click the template and choose 72Zp%a=
* Open. You can then make changes to the template in the Source Editor. ~>2DA$Ec
*/ ?
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package com.tot.count; W^U6O&-K
import java.util.*;
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/** :Q\Es:y
* YoC{ t&rY
* @author Cn\5Vyrl
*/ h>0R!Rl8
public class CountCache { r0MUv}p#|L
public static LinkedList list=new LinkedList(); =yT3#A~<G
/** Creates a new instance of CountCache */ R1,.H92
public CountCache() {} k&JB,d-mJ%
public static void add(CountBean cb){ *\gS 2[S
if(cb!=null){ \/qo2'V
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list.add(cb); B!PT|
} sGBm[lplz
} A=N &(k
} He&7(mQ0^
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CountControl.java UQX.
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/* YJ6y]r
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* CountThread.java v3zd>fDnRp
* Z~X \Z.
* Created on 2007年1月1日, 下午4:57 vw.rkAGY
* Wi;wu*
* To change this template, choose Tools | Options and locate the template under )Bz2-|\
* the Source Creation and Management node. Right-click the template and choose /5**2Kgv1
* Open. You can then make changes to the template in the Source Editor. J&hzr t
*/ a9f!f %9
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package com.tot.count; w(,K
import tot.db.DBUtils; SRP.Mqg9
import java.sql.*; CIt%7
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/** 1\t# *N
* <bvbfS
* @author 4z;@1nN_8a
*/ \zx &5a
#
public class CountControl{ i(Xz3L#(
private static long lastExecuteTime=0;//上次更新时间 v0aV>-v
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 H\>0jr`
/** Creates a new instance of CountThread */ rd
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public CountControl() {} R5"5Z?'
public synchronized void executeUpdate(){ a+-X\qN
Connection conn=null; c}-ADr9
PreparedStatement ps=null; Bd++G'FZ
try{ t^k^e{,q#
conn = DBUtils.getConnection(); |>'.(
conn.setAutoCommit(false); 13JZ\`ceb
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); *ku}.n
for(int i=0;i<CountCache.list.size();i++){ {s{bnU
CountBean cb=(CountBean)CountCache.list.getFirst(); _ArN[]Z
CountCache.list.removeFirst(); x$SxGc~4gb
ps.setInt(1, cb.getCountId()); B2kKEMdGg
ps.executeUpdate();⑴ 8h?):e
//ps.addBatch();⑵ ~dtS
} HL`=zB%
//int [] counts = ps.executeBatch();⑶ :-[y`/R
conn.commit(); |_h$}~;
}catch(Exception e){ qN=l$_UD
e.printStackTrace(); )0 1,3J>#
} finally{
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try{ u4KP;_,m
if(ps!=null) { #$dEg
ps.clearParameters(); m)1+D"z
ps.close(); f{HjM?
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ps=null; kq4ii`zi8
} i"_@iN0N
}catch(SQLException e){} \@8.BCWK
DBUtils.closeConnection(conn); K*/X{3 J;
} c/'Cju W
} + g*s%^(E
public long getLast(){ <Pnz$nH:e
return lastExecuteTime; Sb|9U8h
} <E&8g[x6
public void run(){ $sxm MP
long now = System.currentTimeMillis(); [Yyb)Qf
if ((now - lastExecuteTime) > executeSep) { L|`(u
//System.out.print("lastExecuteTime:"+lastExecuteTime); x
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//System.out.print(" now:"+now+"\n"); 0XzrzT"&
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); AE@N:a
lastExecuteTime=now; r7zS4;b
executeUpdate(); }\?]uNH
} ?= RC?K
else{ 2mt
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); MXP3ZN'
} +
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} K;'s+ZD
} s[n*fV']A
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 1w$X;q"
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类写好了,下面是在JSP中如下调用。 ]n
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<% 1
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CountBean cb=new CountBean(); uLq%Nu
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); S2\|bs7;J,
CountCache.add(cb); P 5_l&
out.print(CountCache.list.size()+"<br>"); Pw|J([
CountControl c=new CountControl(); ,3,(/%=k
c.run(); 7i##g,
out.print(CountCache.list.size()+"<br>"); LDgGVl
%>