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: T+8Yd(:hX
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CountBean.java F?L]Dff
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/* , c.^"5
* CountData.java _h%Jf{nu
*
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* Created on 2007年1月1日, 下午4:44 dg D-"-O
* mY|c7}>V;
* To change this template, choose Tools | Options and locate the template under sA0Ho6
* the Source Creation and Management node. Right-click the template and choose zI88IM7/
* Open. You can then make changes to the template in the Source Editor. !E7gIqo
*/ l9p
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package com.tot.count; /%$Zm^8c
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/** iUKjCq02
* U#<d",I
* @author YV>a 3
*/ FT).$h~+4
public class CountBean { iIfiv<(ChM
private String countType; IPot][ N>
int countId; +Z#=z,.^
/** Creates a new instance of CountData */ K5>3
public CountBean() {} eAHY/Y!
public void setCountType(String countTypes){ 5!0iK9O
this.countType=countTypes; $-_" SWG.
} F`}'^>
public void setCountId(int countIds){ A#>wbHjWF
this.countId=countIds; h'ik3mLH
} hzD)yf
public String getCountType(){ pj'gTQ),0
return countType; gI:g/ R
} Q0*E&;|
public int getCountId(){ r#-
return countId; g
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} g$(Y\`zw
} y"?`MzcJ0
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CountCache.java 4^(x)r
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/* 32GI+NN
* CountCache.java s>9I#_4]
* Vjs2Yenx
* Created on 2007年1月1日, 下午5:01 %<i sdvF
* b:1B
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* To change this template, choose Tools | Options and locate the template under 5nPvEN/
* the Source Creation and Management node. Right-click the template and choose kH g|!
* Open. You can then make changes to the template in the Source Editor. H4Bt.5O*
*/ &-/J~b)"
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package com.tot.count; DpHubqWz
import java.util.*; LP3#f{U
/** >^8O :.
* 288mP]a(v_
* @author mF
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*/ dJ"44Wu+J
public class CountCache { r*HSi.'21
public static LinkedList list=new LinkedList(); cT(nKHL
/** Creates a new instance of CountCache */ Gm+D1l i
public CountCache() {}
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public static void add(CountBean cb){ &H_/`Z]Q
if(cb!=null){ GtRpgM
list.add(cb); +:A `e+\
} 6Dd>ex!-A
} k_g@4x1y*
} <?7CwW
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CountControl.java /X8a3Eqp9
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/* COi15( G2
* CountThread.java m?-)SA
* V7$ m.P#uM
* Created on 2007年1月1日, 下午4:57 Yjg$o:M
* 3P_.SF
* To change this template, choose Tools | Options and locate the template under 1@Ba7>%'
* the Source Creation and Management node. Right-click the template and choose H c/7x).
* Open. You can then make changes to the template in the Source Editor. e`Yj}i*bx]
*/ h!B{7J
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package com.tot.count; $GoS?\G
import tot.db.DBUtils; 9^^\Z5
import java.sql.*; x]VycS
/** B"v*[p?
* i7RK*{
* @author R0M>'V?e
*/ ^|/<e?~I
public class CountControl{ HOD?i_
private static long lastExecuteTime=0;//上次更新时间 pIIp61=$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 =K@LEZZ'/<
/** Creates a new instance of CountThread */ f}dlQkZ(
public CountControl() {} Vc\g"1x
public synchronized void executeUpdate(){ clDn=k<
Connection conn=null; mjOxmwo
PreparedStatement ps=null; /}u:N:HA%
try{ b'(AVA
conn = DBUtils.getConnection(); Ioe.[&o6B
conn.setAutoCommit(false); s-#@t
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); uNewWtUb(
for(int i=0;i<CountCache.list.size();i++){ mB2}(DbhE
CountBean cb=(CountBean)CountCache.list.getFirst(); (R=ZI
CountCache.list.removeFirst(); [KUkv
ps.setInt(1, cb.getCountId()); `&I6=,YLp
ps.executeUpdate();⑴ ~ESw* 6s9
//ps.addBatch();⑵ <\*)YKjn/@
} {9J|\Zz3
//int [] counts = ps.executeBatch();⑶ W3l[a^1d
conn.commit(); d{TcjZ
}catch(Exception e){ $%U}k=-
e.printStackTrace(); hl[<o<`Q
} finally{ yXkQ
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try{ l>jrY1u
if(ps!=null) { %n]jsdE^|
ps.clearParameters(); J^t0M\
ps.close(); Qfe u3AT
ps=null; C,,T7(: k
} aT/2rMKPF
}catch(SQLException e){} BTsvL>Wy
DBUtils.closeConnection(conn); xb7!!PR
} d%@0xsU1
} VK4UhN2
public long getLast(){ l="(Hp%b
return lastExecuteTime; qY&(O`?m&
} Cpzd k~+H
public void run(){ tzl,r"k3
long now = System.currentTimeMillis(); [1~3\-Y
if ((now - lastExecuteTime) > executeSep) { %B&O+~
//System.out.print("lastExecuteTime:"+lastExecuteTime); 4FnePi~i
//System.out.print(" now:"+now+"\n"); DKo6lP`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); qV=O;
lastExecuteTime=now; )~P<ruk>,C
executeUpdate(); Zy Df@(z`
} DmoY],9I+p
else{ VK9E{~0=
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); !'\(OFv9Im
} ?:q"qwt$F
} 0r@LA|P
} Jv(E'"H
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 jHMP"(]
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类写好了,下面是在JSP中如下调用。 mj9|q8v{+
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<% &WCVdZK:
CountBean cb=new CountBean(); yR F+
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); B8cg[;e81
CountCache.add(cb); wV-N\5!r%H
out.print(CountCache.list.size()+"<br>"); ?,v@H$)3_
CountControl c=new CountControl(); X:FyNUa
c.run(); ;J?fK69%
out.print(CountCache.list.size()+"<br>"); ^=I[uX-3ue
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