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: %e_WO,R
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CountBean.java ]SK (cfA`
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/* lk8VJ~2d
* CountData.java YTY0N5["
* IUzRE?Kzf
* Created on 2007年1月1日, 下午4:44 L&l>?"_
* `OduBUI]]
* To change this template, choose Tools | Options and locate the template under Y5K!DMKY
* the Source Creation and Management node. Right-click the template and choose F|V?Z
* Open. You can then make changes to the template in the Source Editor. S!rUdxO
*/ -O2QzzE&
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package com.tot.count; ao
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/** Rd 2*
* Dt8eVWkN ~
* @author Y8Mo .v
*/ N#|c2n+
public class CountBean { P||u{]vU
private String countType; brZ3T`p+.P
int countId; wp$SO^?-
/** Creates a new instance of CountData */ LM0TSB?
public CountBean() {} ucTkWqG
public void setCountType(String countTypes){ -6#i~a]
this.countType=countTypes; WMrK8e'
} T_pE 'U%[
public void setCountId(int countIds){ 1298&C@
this.countId=countIds; /K'Kx
} F*}b),
public String getCountType(){ 3<B{-z
return countType; <;M 6s~
} &u$l2hSS
public int getCountId(){ |IZG`3
return countId; )-[X^l
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} Y ||!V
} SxMh '
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CountCache.java Z3 &8(vw
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/* }k'8*v}8
* CountCache.java DAJh9I
* df}B:?Ew.
* Created on 2007年1月1日, 下午5:01 k5W5 9tz
* IgZX,4i=o
* To change this template, choose Tools | Options and locate the template under .] 5&\
* the Source Creation and Management node. Right-click the template and choose rY88xh^
* Open. You can then make changes to the template in the Source Editor. L[rJ7:
*/ )6Z)z;n]aW
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package com.tot.count; wMei`svY
import java.util.*; 9NKZE?5P|D
/** 0A\o8T.12
* !dGy"-i$h
* @author -H{c@hl
*/ n6
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public class CountCache { foaNB=,
public static LinkedList list=new LinkedList(); o
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/** Creates a new instance of CountCache */ @~/LsYA:
public CountCache() {} (eG#JVsm9
public static void add(CountBean cb){ ,NKDEcw]
if(cb!=null){ Eo)n(
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list.add(cb); V<P@hAAr
} mLKwk6I
} >e"1a/2%>&
} 4LKOBiEM
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CountControl.java :@ 19,.L
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/* ln#Lx&r;|
* CountThread.java 7_n@iUG2n
* MvJEX8M
* Created on 2007年1月1日, 下午4:57 `[/BG)4
* L)4TW6IUk
* To change this template, choose Tools | Options and locate the template under &\`=}hB
* the Source Creation and Management node. Right-click the template and choose m>:3Ku
* Open. You can then make changes to the template in the Source Editor. /k(0}g=\
*/ $ v$~.
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package com.tot.count; L0_R2EA
import tot.db.DBUtils; 9kQ~)4#
import java.sql.*; B?$pIG^Mn
/** OT\[qaK
* dy#dug6j
* @author x}].lTjD
*/ @tRq(*(/:
public class CountControl{ jvCk+n[
private static long lastExecuteTime=0;//上次更新时间 mS0*%[S {
private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ fLxFF
public CountControl() {} DpoRR`
public synchronized void executeUpdate(){ %dKUB4
Connection conn=null; bxK1v7
PreparedStatement ps=null; 83Bp_K2\
try{ e:6R +8s2
conn = DBUtils.getConnection(); LezM=om.
conn.setAutoCommit(false); aB#qzrr['8
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 8lT.2H
for(int i=0;i<CountCache.list.size();i++){ WdnCRFO?l
CountBean cb=(CountBean)CountCache.list.getFirst(); %7z
CountCache.list.removeFirst(); jun>(7
ps.setInt(1, cb.getCountId()); .COY%fz
ps.executeUpdate();⑴ 7.hn@_
//ps.addBatch();⑵ zgJ%Zr!~
} ccZ A
//int [] counts = ps.executeBatch();⑶ t%/Y^N;
conn.commit(); Y*dzoN.sW
}catch(Exception e){ v](7c2;
e.printStackTrace(); hF.9\X]
} finally{ Yhb=^)@))
try{ tHJ#2X#Y.
if(ps!=null) { "fL:scq@0
ps.clearParameters(); th2a'y=0
ps.close(); ZH~ T'Bg
ps=null; :W? 7J"
} ?6; +.h\
}catch(SQLException e){} K#}DXq
DBUtils.closeConnection(conn); BOoLs(p
} $7T3wv9
} A|O7W|"W
public long getLast(){ x{6/di
return lastExecuteTime; L/_OgL]YdI
} Ir_K83VM
public void run(){ W]4Gs;
long now = System.currentTimeMillis(); 3<AZ,gF1
if ((now - lastExecuteTime) > executeSep) { 9pb4!=g*
//System.out.print("lastExecuteTime:"+lastExecuteTime); % tN{
//System.out.print(" now:"+now+"\n"); w<|^i*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
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lastExecuteTime=now; `s Az1/N
executeUpdate(); x%jJvwb^|
} `u3to{
else{ $,bLK|<hi
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6OkN(tL&.
} pkWzaf
} I;S[Ft8d
} $RuJm\f
//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 %}MZWf{
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类写好了,下面是在JSP中如下调用。 X@*$3z#Z
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<% aK,\e/Oo
CountBean cb=new CountBean(); 3z#fFP@E
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 1.~^QH\p?3
CountCache.add(cb); .>y3`,0h
out.print(CountCache.list.size()+"<br>"); +_f813$C
CountControl c=new CountControl();
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c.run(); 5$$]ZMof
out.print(CountCache.list.size()+"<br>"); A9[D.W9>
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