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: {.v-
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CountBean.java DfgqB3U[
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/* xH!{;i
* CountData.java Wg9q_Ql
* v>CAA"LH
* Created on 2007年1月1日, 下午4:44 Z%Q[W}iD
* ,{MA90!
* To change this template, choose Tools | Options and locate the template under T|`nw_0
* the Source Creation and Management node. Right-click the template and choose !%>p;H%0
* Open. You can then make changes to the template in the Source Editor. PB*mD7"
*/ 9ar+P h@*
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package com.tot.count; ue@ fry
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/** . S4Xw2MS
* (9$z+Zmm?
* @author MX2Zm
*/ //S/pCqED
public class CountBean { =Bu>}$BD
private String countType; BWV)>
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int countId; YYwFjA@
/** Creates a new instance of CountData */ i;>Yx#
public CountBean() {} 8`l bKV
public void setCountType(String countTypes){ :1NF#-2\f
this.countType=countTypes; (+lwt
} qKag'0e
public void setCountId(int countIds){ E9JxntX
this.countId=countIds; _0p8FhNt
} RGvfy/T
public String getCountType(){ yU]NgG=z:-
return countType; /@-!JF#g
} Ey7SQb
public int getCountId(){ IIcG+zwx
return countId; Gv?3T Am8
} ;5QdT{$H
} 3.>M=K~09
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CountCache.java }xXUCU<
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/* ]/&qv6D*d
* CountCache.java 5'>DvCp%M
* ,Axk\7-
* Created on 2007年1月1日, 下午5:01 DtLga[M
* VJquB8?H
* To change this template, choose Tools | Options and locate the template under BnJpC<xm
* the Source Creation and Management node. Right-click the template and choose r/o1a't;
* Open. You can then make changes to the template in the Source Editor. uL| Wuq
*/ "@uKe8r|y
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package com.tot.count; 3VNYDY`>
import java.util.*; G+&ug`0]5
/** r$<-2lW
* Q{FK_Mv<
* @author :98<dQIG
*/ W
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public class CountCache { ,`kag~bZ
public static LinkedList list=new LinkedList(); =Ts2a"n
/** Creates a new instance of CountCache */ 8[@aX;I
public CountCache() {} mAO$gHQ
public static void add(CountBean cb){ 5DB4 vh
if(cb!=null){ &/)2P#u
list.add(cb); >G`Uc&=
} ZYf0FC=-
} Mkc
} .yK~FzLs
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CountControl.java `wIMu$i
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/* ]34fG3D|
* CountThread.java kF{'?R5w
* #_oN.1u57
* Created on 2007年1月1日, 下午4:57 ^\o 3V<
* {"f4oK{w
* To change this template, choose Tools | Options and locate the template under qaE>])
* the Source Creation and Management node. Right-click the template and choose r2dU>U*:4
* Open. You can then make changes to the template in the Source Editor. [\|`C4@3a
*/ \M$e#^g
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package com.tot.count; r:rM~``
import tot.db.DBUtils; i3
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import java.sql.*; n[|*[II
/** K,B qVu
* S)`%clN}J
* @author \0bao<
*/ 7T7
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public class CountControl{ l=+hs
private static long lastExecuteTime=0;//上次更新时间 aYy+iP'$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7ns n8WN[
/** Creates a new instance of CountThread */ 8rZJvE#c
public CountControl() {} y^OT0mZkg
public synchronized void executeUpdate(){ pf&H !-M
Connection conn=null; | R\PQ/)
PreparedStatement ps=null; mV~aZM0'
try{ } J_"/bB
conn = DBUtils.getConnection(); 4th*=ku
conn.setAutoCommit(false); .5?e)o)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); R*S9[fqC[
for(int i=0;i<CountCache.list.size();i++){ |j2b=0Rpk
CountBean cb=(CountBean)CountCache.list.getFirst(); 'BUix!k0<
CountCache.list.removeFirst(); (%N=7?
ps.setInt(1, cb.getCountId()); !]#@:Z
ps.executeUpdate();⑴ /sU~cn^D5
//ps.addBatch();⑵ R_JB`HFy=
} VK)vb.:
//int [] counts = ps.executeBatch();⑶ R%%Uw %`
conn.commit(); <vb%i0+b.^
}catch(Exception e){ &7-ENg9 [
e.printStackTrace(); <I
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} finally{ w;
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try{ &|]GTN`E
if(ps!=null) { 8D]&wBR:
ps.clearParameters(); 9-B/n0
ps.close(); `#g62wb,HY
ps=null; ~-J!WC==U
} d+m}Z>iQ1O
}catch(SQLException e){} }Mv$Up
DBUtils.closeConnection(conn); u)X]]6YJ
} +Oxw?`I$
} 0gevn
public long getLast(){ -!bfxbP
return lastExecuteTime; ScCp88KpFI
} 6y0CEly>3#
public void run(){ VoG_'P
long now = System.currentTimeMillis(); OTy{:ID
if ((now - lastExecuteTime) > executeSep) { ":I@>t{H*
//System.out.print("lastExecuteTime:"+lastExecuteTime); R(t1Ei.-?
//System.out.print(" now:"+now+"\n"); \86:f<)P
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); D*_Z"q_B
lastExecuteTime=now; &eA!h
executeUpdate(); " J4?Sb <
} d~QZcR
else{ fK
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [@_IUvf^.
} 1#w'<}h#U
} k00&+C
} E[=#Rw!*
//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 {9c_T!c
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类写好了,下面是在JSP中如下调用。 N{}o*K
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<% oR@emYL
CountBean cb=new CountBean(); l_lK,=cLj+
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); px=k&|l
CountCache.add(cb); "AuU5G 9'I
out.print(CountCache.list.size()+"<br>"); C#l9MxZE
CountControl c=new CountControl(); )a=FhSB[G
c.run(); 4 (>8tP\Y
out.print(CountCache.list.size()+"<br>"); hy}n&h
%>