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: 3=G5(0
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CountBean.java &zg$H,@Qp
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/* ;_Of`C+
* CountData.java %i]uW\~U
* v"Ud mv "
* Created on 2007年1月1日, 下午4:44 D
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* X,C/x)
* To change this template, choose Tools | Options and locate the template under ><:lUt*N2
* the Source Creation and Management node. Right-click the template and choose jmA{rD W
* Open. You can then make changes to the template in the Source Editor. Cs6zv>SR
*/ >uqS
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package com.tot.count; RfVV(X
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/** cr=FMfhB
* )sz2 9
* @author jP6oJcZ
*/ VK@i#/jm
public class CountBean { k:HSB</}
private String countType; ys"mP*wD
int countId; \8@[bpI@g
/** Creates a new instance of CountData */ h#6 jUQ
public CountBean() {} NIXc ib"tG
public void setCountType(String countTypes){ n<Xm%KH.
this.countType=countTypes; V~gUMu4ot
} ZF11v(n
public void setCountId(int countIds){ #k|g9`
this.countId=countIds; K:lT-*+S
} QVZ6;/
public String getCountType(){ v#YS`];B
return countType; zLIa! -C
} MWd_6XM
public int getCountId(){ TckR_0LNV
return countId; LF3GVu,
} >TJKH^7n
} ^VLUZ
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CountCache.java %q\P 'cK
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/* GXvo't@N
* CountCache.java I!i#=
* `sp'Cl!
* Created on 2007年1月1日, 下午5:01 #t9=qR~"
* rc{[\1 -N
* To change this template, choose Tools | Options and locate the template under l4B O@
* the Source Creation and Management node. Right-click the template and choose %imBGh
* Open. You can then make changes to the template in the Source Editor. S|5lx7
*/ HDae_.
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package com.tot.count; W U4vb
import java.util.*; kl{OO%jZ
/** odT7Gq
* />j+7ts
* @author >|o9ggL`J5
*/ & b^*N5<Z
public class CountCache { Gv2./<{#
public static LinkedList list=new LinkedList(); PTc\I
/** Creates a new instance of CountCache */ G<WDyoN=O
public CountCache() {} @W5hrei
public static void add(CountBean cb){ JV6U0$g_S
if(cb!=null){ r
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list.add(cb); @xM!:
} x)qHeS
} \5pAG
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} %dWFg<< |
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CountControl.java ;g)Fhdy!
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/* =K<I)2
* CountThread.java uB%^2{uU
* c+K=pp@
* Created on 2007年1月1日, 下午4:57 vgbjvyfN
* UFY~D"%/
* To change this template, choose Tools | Options and locate the template under $(mdz)Cfy
* the Source Creation and Management node. Right-click the template and choose =&g}Y
* Open. You can then make changes to the template in the Source Editor. H2R^t{w
*/ ] GPz>k
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package com.tot.count;
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import tot.db.DBUtils; ?%fZvpn -
import java.sql.*; 87 E3pe
/** 3usA
* CR PE?CRQF
* @author :W<,iqSCm
*/ WHj4#v(
public class CountControl{ WuQ<AS=
private static long lastExecuteTime=0;//上次更新时间 #1hz=~YO
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 H?bsK~
/** Creates a new instance of CountThread */ v+_Y72h*a
public CountControl() {} )B5gs%u]
public synchronized void executeUpdate(){ Y\9*e5?`I3
Connection conn=null; U:p"IY#%
PreparedStatement ps=null; $=QO_t)?
try{ %oKc?'L0
conn = DBUtils.getConnection(); xgw)`>p,W
conn.setAutoCommit(false); Bst>9V&R
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); &"6ktKrIg
for(int i=0;i<CountCache.list.size();i++){ )KhVUFS1
CountBean cb=(CountBean)CountCache.list.getFirst(); K1{nxw!`
CountCache.list.removeFirst(); 5i-;bLm
ps.setInt(1, cb.getCountId()); zc~xWy+
ps.executeUpdate();⑴ Vwg|? sG_
//ps.addBatch();⑵ `}Zbfe~
} 1,!\7@<CT
//int [] counts = ps.executeBatch();⑶ 6f9<&dCK
conn.commit(); Y52xrIvl\
}catch(Exception e){ @X><lz
e.printStackTrace(); 4bjp*1 *]
} finally{ 7,VWvmWJex
try{ E/-Kd!|"
if(ps!=null) { W%ZU& YBc
ps.clearParameters(); MxA'T(Ay
ps.close(); W]MJ!4
ps=null; qvT+d
l3#[
} }Fe{s;
}catch(SQLException e){} 9nAK6$/
DBUtils.closeConnection(conn); QN8Hz/}\
} 5va&N<U
} ={vtfgxl
public long getLast(){ &UH z
return lastExecuteTime; v7u}nx
} hg/&[/eodm
public void run(){ e>9{36~jh
long now = System.currentTimeMillis(); !td.ks0
if ((now - lastExecuteTime) > executeSep) { _llaH
//System.out.print("lastExecuteTime:"+lastExecuteTime); l'8TA~
//System.out.print(" now:"+now+"\n"); =QO[zke:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); fv'P!+)t
lastExecuteTime=now; Dk6\p~q
executeUpdate(); /1
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} >gLyz2
else{ n|2-bRK-
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); K T72D
} vX24W*7
} 84\o7@$#
} zd]L9 _
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ^G<M+RF2J
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类写好了,下面是在JSP中如下调用。 'ZgW~G]S
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<% 8=AKOOU7>
CountBean cb=new CountBean(); HCy} '}d
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )cBV;
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CountCache.add(cb); qf$|z`c
out.print(CountCache.list.size()+"<br>"); 1h0ohW
CountControl c=new CountControl(); 'MlC
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c.run(); =+\oL!^
out.print(CountCache.list.size()+"<br>"); KTJ$#1q
%>