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: W6L}T,epX
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CountBean.java JN<IMH
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/* Ilv
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* CountData.java
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* &Ez]pKjB
* Created on 2007年1月1日, 下午4:44 D$PR<>=y
* 8VLD yX2-
* To change this template, choose Tools | Options and locate the template under .80L>0
* the Source Creation and Management node. Right-click the template and choose 7) e#b
* Open. You can then make changes to the template in the Source Editor. Kk<MS$Ov
*/ 4xnM7t\
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package com.tot.count; ey! {
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/** d}_%xkC
* *u?N{LkqS
* @author [I4&E >
*/ @T8$/
public class CountBean { =VM4Q+'K
private String countType; z9IJ%=R
int countId; ,?ci+M)
/** Creates a new instance of CountData */ z{ydP Ra
public CountBean() {} (#%R'9Rv
public void setCountType(String countTypes){ G2e0\}q
this.countType=countTypes; `Wy8g?d;bn
} Tv`-h
public void setCountId(int countIds){ kr6^6I.
this.countId=countIds; +oe%bk|A
} 84UI)nE:Q
public String getCountType(){ ?~s2 3%E
return countType; _M9-n
} 7l|D!`BS
public int getCountId(){ v|K<3@J
return countId; 2[Q/|D}}|
} KMZEUmY1R1
} Y~ ( <H e?
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CountCache.java s5SKQ#,@P
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/* nlaeo"]
* CountCache.java cri.kr9Y
* s
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* Created on 2007年1月1日, 下午5:01 k| Ye[GM*
* hY-;Vh0J
* To change this template, choose Tools | Options and locate the template under SFRQpQ06
* the Source Creation and Management node. Right-click the template and choose LAfv1
* Open. You can then make changes to the template in the Source Editor. o,;Hb4Eu
*/ y&8kORz;?
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package com.tot.count; ~76qFZe-
import java.util.*; -L)b;0%
/** -)2sR>`A%
* :KL5A1{
* @author =zXii{t
*/ qH-':|h7
public class CountCache { H<bK9k)E
public static LinkedList list=new LinkedList(); ^J_rb;m43
/** Creates a new instance of CountCache */ GVt}\e~"
public CountCache() {} S|HnmkV66
public static void add(CountBean cb){ g4fe(.?c,
if(cb!=null){ Z_Z; g]|!
list.add(cb); T6=q[LpsKN
} % HK \
} {Y#$
} MEZc/Ru-[
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CountControl.java "Ooc;xD3<
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/* k yI -nE
* CountThread.java Rh.CnCbM
* 5,n{-V
* Created on 2007年1月1日, 下午4:57 :Kt'Fm,s?
* hB:}0@l6p=
* To change this template, choose Tools | Options and locate the template under 9V5d=^
* the Source Creation and Management node. Right-click the template and choose K)d]3V!
* Open. You can then make changes to the template in the Source Editor. <R>%DD=v^
*/ uh_2yw_
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package com.tot.count; Y']D_\y
import tot.db.DBUtils; =
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import java.sql.*; 16N+
/** WMw]W&
* 4`Z8EV
* @author !^EdB}@yS
*/ bn8`$FA^
public class CountControl{ 39+6ZTqx
private static long lastExecuteTime=0;//上次更新时间 g.re`m|Aj
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 w2/3\3p
/** Creates a new instance of CountThread */ !33)6*s
public CountControl() {} a~nErB
public synchronized void executeUpdate(){ ILQB%0!
Connection conn=null; D+"-(k
PreparedStatement ps=null; &+Iv"9
try{ 2/]74d8
conn = DBUtils.getConnection(); _:Jra
conn.setAutoCommit(false); ^`&?"yj<z
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Cm5:_K`;]
for(int i=0;i<CountCache.list.size();i++){ R^*h|7)E
CountBean cb=(CountBean)CountCache.list.getFirst(); Z1t?+v+Ro*
CountCache.list.removeFirst(); dY'mY ~Tv
ps.setInt(1, cb.getCountId()); vS$_H<;P
ps.executeUpdate();⑴ Mx<?c
//ps.addBatch();⑵ KS6H`Mm}/
} UD@u hL
//int [] counts = ps.executeBatch();⑶
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conn.commit(); ;F:~HrxT}
}catch(Exception e){ =gjq@N]lAW
e.printStackTrace(); M_Qv{
} finally{ J0eJRs
try{ =Q!)xEK
if(ps!=null) { >){"x(4`
ps.clearParameters(); /QeJ#EHn
ps.close(); iO,_0Y4
ps=null; ,py:e>+^t
} O0Vtvbj
}catch(SQLException e){} _FRwaFVJ3
DBUtils.closeConnection(conn); t'{\S_
} U0Y;*_>4
} fZ*LxL
public long getLast(){ .<Lbv5m
return lastExecuteTime; =Bq3O58+
} RrPo89o
public void run(){ +TQMA>@g<
long now = System.currentTimeMillis(); !k= ~5)x
if ((now - lastExecuteTime) > executeSep) { nbGB84
//System.out.print("lastExecuteTime:"+lastExecuteTime); #`>46T
//System.out.print(" now:"+now+"\n"); #s-^4znv9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); dD Zds
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lastExecuteTime=now; HaUfTQ8
executeUpdate(); d
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} xp4w9.X5(
else{ yl=_ /'*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); UY!N"[&
} E_[)z%&n2
} *61+Fzr
} q*^F"D:?k
//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 4%3R}-'mh
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类写好了,下面是在JSP中如下调用。 JFvVRGWB
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<% 9EE},D
CountBean cb=new CountBean(); 2'38(wXn#
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); `a!:-.:v
CountCache.add(cb); !p4y@U{
out.print(CountCache.list.size()+"<br>"); p..O;_U
CountControl c=new CountControl(); z DP
c.run(); .)zX<~,
out.print(CountCache.list.size()+"<br>"); Wx i|(}
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