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: heQyz|o
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CountBean.java O2"5\@HfE
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/* pKaU
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* CountData.java sq?js#C5
* Ty} Y/jW
* Created on 2007年1月1日, 下午4:44 /h9v'Y}c
* 8&3KVd`
* To change this template, choose Tools | Options and locate the template under HJJ;gTj
* the Source Creation and Management node. Right-click the template and choose t8M\
* Open. You can then make changes to the template in the Source Editor. ]EdZ,`B4
*/ y%O^Zm1
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package com.tot.count; a9NIK/9
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/** ^0 &jy:{
* Hb0_QT~
* @author |G_, 1$
*/ *P8CzF^>\&
public class CountBean { opTH6a
private String countType; a[p$e?gka
int countId; "RgP!
/** Creates a new instance of CountData */ i6<uj
public CountBean() {} & H8 %
public void setCountType(String countTypes){ {.ypZ8JU
this.countType=countTypes; _=}.Sg5Q
} u~PZK.Uf0
public void setCountId(int countIds){ Iw?*y.z|
this.countId=countIds; 2#/23(Wc
} &OA6Zw/A
public String getCountType(){ FC
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return countType; vo(:g6$
} L7R!,
public int getCountId(){ r+k&W
return countId; 6|IJwP^Q_
} -ijzo%&qA
} q3C
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CountCache.java IwRP,MQ~
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/* _>ZC;+c?
* CountCache.java N3N~z1x0h
* 41P0)o
* Created on 2007年1月1日, 下午5:01 #<X4RJ
* @ qi|}($
* To change this template, choose Tools | Options and locate the template under "U+c`V=w
* the Source Creation and Management node. Right-click the template and choose eK5~YM:o
* Open. You can then make changes to the template in the Source Editor. G|RBwl
*/ (:F]@vT
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package com.tot.count; KDP"z
import java.util.*; &nwS7n1eb
/** zliMG=6
* Pm%5c\ef
* @author
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*/ 3Gr"YG{,
public class CountCache { J5n6K$.d
public static LinkedList list=new LinkedList(); pL!,1D!
/** Creates a new instance of CountCache */ %?, 7!|Ls
public CountCache() {} #d*0
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public static void add(CountBean cb){ E)`0(Z:E
if(cb!=null){ Vr Lp5?Bh
list.add(cb); QAt]sat
} [VqiF~o,
} egBk7@Ko
} P3-O)m]jv
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CountControl.java ?i V}U
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/* `"PHhCG+z
* CountThread.java U;IGV~oT
* vH-|#x~
* Created on 2007年1月1日, 下午4:57 |&xaV-b9W
* :*BN>*1^\r
* To change this template, choose Tools | Options and locate the template under H }]Zp
* the Source Creation and Management node. Right-click the template and choose I'^XEl?
* Open. You can then make changes to the template in the Source Editor. )">#bu$
*/ )P? F ni}
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package com.tot.count; $]Ix(7@W
import tot.db.DBUtils; 1|-C(UW>
import java.sql.*; mt0v (
/** lul
* '_Pb\
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* @author 0S; Ipg
*/ S1)g\Lv
public class CountControl{ ZVJ6 {DS/
private static long lastExecuteTime=0;//上次更新时间 5uSg]2:
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |x1Ttr,
/** Creates a new instance of CountThread */ 35AH|U7b
public CountControl() {} }j1;0 kb?
public synchronized void executeUpdate(){ {wt9/IlG1
Connection conn=null; SJO*g&duQ
PreparedStatement ps=null; 8KigGhY'ms
try{ J0e^v
conn = DBUtils.getConnection(); []N&,2O
conn.setAutoCommit(false); Sh-B!
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); P|?nx"c
for(int i=0;i<CountCache.list.size();i++){ {Fyw<0 [@
CountBean cb=(CountBean)CountCache.list.getFirst(); ;sf'"UnL
CountCache.list.removeFirst(); ? N]bFW"t|
ps.setInt(1, cb.getCountId()); knHrMD;
ps.executeUpdate();⑴ rO#$SW$YW
//ps.addBatch();⑵ [a$1{[|)
} X=6L-^o)
//int [] counts = ps.executeBatch();⑶ x~8R.Sg
conn.commit(); Gv 8Z
}catch(Exception e){ 2fc+PE
e.printStackTrace(); gGA5xkA
} finally{ h<?I?ZR0$
try{ L:lnm9<
if(ps!=null) { #q0xlF@
ps.clearParameters(); iK'A m.o+
ps.close(); }l]r-
ps=null; JPT&!%~
} 5qqU8I
}catch(SQLException e){} kIt1k w
DBUtils.closeConnection(conn); aG@GJ@w
} V)`Q0}
} hdM?Uoo(4a
public long getLast(){ QiRx2Z*\
return lastExecuteTime; JL:B4f%}B
} FEa%wS{
public void run(){ Pff-eT+~m
long now = System.currentTimeMillis(); hiR+cPSF
if ((now - lastExecuteTime) > executeSep) { OQuTM[W
//System.out.print("lastExecuteTime:"+lastExecuteTime); &|zV Wl
//System.out.print(" now:"+now+"\n"); J(XK%e[8
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); )In;nc
lastExecuteTime=now; V-i:t,*lk(
executeUpdate(); )OGO
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} cetlr
else{ E/ku VZX
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Z>@\!$Mc
} dUceZmAl
} )[t3-'
} *q Ins/@
//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 6XeqK*r*
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类写好了,下面是在JSP中如下调用。 (G"/C7q
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<% 1;MUemnx`
CountBean cb=new CountBean(); 3e^'mT
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {+QQ<)l^tJ
CountCache.add(cb); 9>5]y}.{
out.print(CountCache.list.size()+"<br>"); L w/ZKXDU2
CountControl c=new CountControl(); yucbEDO.
c.run(); ou&7v<)x4
out.print(CountCache.list.size()+"<br>"); Z:MU5(Te
%>