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: sw[<VsxjR
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CountBean.java
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/* }{P&idkv
* CountData.java t>XZ3
* [kVpzpGr
* Created on 2007年1月1日, 下午4:44 \a\^(`3a[
* *oKgP8CF
* To change this template, choose Tools | Options and locate the template under \o0z@Ntq
* the Source Creation and Management node. Right-click the template and choose MacL3f
* Open. You can then make changes to the template in the Source Editor. X *_
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*/ GH[
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package com.tot.count; n iXHK$@5
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/** z?8zFP
* $0S.@wUG
* @author ;JMOsn}8
*/ cpP.7ZR
public class CountBean { V22q*/iV
private String countType; #-l!`\@
int countId; MBnK&GS
/** Creates a new instance of CountData */ at_dmU2[7
public CountBean() {} A}az
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public void setCountType(String countTypes){ *?EjYI
this.countType=countTypes; " 8~f
} s^{{@O.
public void setCountId(int countIds){ iKP\/LR<n
this.countId=countIds; "~.8eKRQ
} g?k#wj1uH
public String getCountType(){ S-H-tFy\\
return countType; sDz)_;;%
} FCS5@l,'<
public int getCountId(){ 'lQ
return countId; 'fp<FeTg
} *y":@T
}
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CountCache.java EhmUX@k],
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/* '<*CD_2t-
* CountCache.java yg-L^`t+B5
* \4]zNV ~x
* Created on 2007年1月1日, 下午5:01 y \mutm
* hIE%-gZ/
* To change this template, choose Tools | Options and locate the template under |wyJh"4!
* the Source Creation and Management node. Right-click the template and choose wfU&{7yt
* Open. You can then make changes to the template in the Source Editor. 8Izn'>"
*/ P!>{>r4
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package com.tot.count; L*SSv
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import java.util.*; 2Be ?5+
/** YokZar2a0
* 1DI"LIL
* @author G{&yzHAuae
*/ 3<~2"@J
public class CountCache { h1G*y
public static LinkedList list=new LinkedList(); u+I r:k
/** Creates a new instance of CountCache */
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public CountCache() {} )$Dcrrj
public static void add(CountBean cb){ GtAJ#[5w
if(cb!=null){ &?5{z\;1"
list.add(cb); f2SU5e2
} u]>>B>KOJ7
} h.}t${1ZC
} :+?W
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CountControl.java cA (e"N
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/* 35N/v G0
* CountThread.java '%]@a7w
* #)h
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* Created on 2007年1月1日, 下午4:57 =|WV^0=S'%
* Fv7%TK{oe
* To change this template, choose Tools | Options and locate the template under >`rNT|rg
* the Source Creation and Management node. Right-click the template and choose GJ^]ER-K
* Open. You can then make changes to the template in the Source Editor. l:5CM[mZ
*/ E;GR;i{t
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package com.tot.count; 5w [=
import tot.db.DBUtils; N|Cy!E=d
import java.sql.*; *|gs-<[#X
/** w;SH>Ax:
* :z0>H5
* @author BHJ'[{U*w
*/ ,wb|?>Y
public class CountControl{ :?:j$
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private static long lastExecuteTime=0;//上次更新时间 uZiY<(X
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 KZ<RDXV T
/** Creates a new instance of CountThread */ 4gkV]"
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public CountControl() {} N5 rG.6K
public synchronized void executeUpdate(){ ?m_R U
Connection conn=null; &6^W%r
PreparedStatement ps=null; 5q_OuZ/6
try{ :kiO
conn = DBUtils.getConnection(); )`+@j.75
conn.setAutoCommit(false); 1-NX>E5
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); q
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for(int i=0;i<CountCache.list.size();i++){ 4(0t
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CountBean cb=(CountBean)CountCache.list.getFirst(); q[|`&6B
CountCache.list.removeFirst(); R;TEtu7
ps.setInt(1, cb.getCountId()); a6k(O8Ank3
ps.executeUpdate();⑴ @<TfA>*VJ
//ps.addBatch();⑵ Z/05 wB
} ?'/5%f`
//int [] counts = ps.executeBatch();⑶ ATmqq)\s
conn.commit(); ;Y|~!%2~
}catch(Exception e){ $@qs(Xwr
e.printStackTrace(); \Af|$9boHz
} finally{ &<P^Tvqq&
try{ v.LUK
if(ps!=null) { V&+$Vq
ps.clearParameters(); -^jLU
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ps.close(); h. (;GJO
ps=null; #HuA(``[d
} |^k1hX2?W
}catch(SQLException e){} x^O2Lj,w\
DBUtils.closeConnection(conn); 6L> "m0
} vwH7/+
} PLD'Q,R
public long getLast(){ E e\-q
return lastExecuteTime; (F
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} <&0*5|rR
public void run(){ 9H%xZ(`vN
long now = System.currentTimeMillis(); L%O8vn^3
if ((now - lastExecuteTime) > executeSep) { AW&s-b%P
//System.out.print("lastExecuteTime:"+lastExecuteTime); &|\}\+0Z
//System.out.print(" now:"+now+"\n"); OZ14-}Lr5
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >\.[}th}
lastExecuteTime=now; :+^$?[6]
executeUpdate(); No&[ \;
} -zLI!F 0
else{ P5xmLefng
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); L8tLW09
} /^eemx
} t{s*3k/
} 2T%f~yQ^
//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 <IDzv'
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类写好了,下面是在JSP中如下调用。 =egi?Ne
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<% ~rX6owBq
CountBean cb=new CountBean(); T_%]#M
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^`MDP`M;
CountCache.add(cb); sfPN\^k2
out.print(CountCache.list.size()+"<br>"); 7-IeJ6,D
CountControl c=new CountControl(); to|9)\
c.run(); ViT 5Jn7
out.print(CountCache.list.size()+"<br>"); i6:yNb ='
%>