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: U6 R"eQUTV
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CountBean.java ]B;\?Tim
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/* pX nY=
* CountData.java #DL( %=:
* oZY2K3J)
* Created on 2007年1月1日, 下午4:44 0^27grU>
* Xg](V.B6
* To change this template, choose Tools | Options and locate the template under RnA>oKc
* the Source Creation and Management node. Right-click the template and choose j\ dY
* Open. You can then make changes to the template in the Source Editor. ,s?7EHtC
*/ |]<eJ|\=
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package com.tot.count; c]y"5;V8
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/** 6__#n`
* QzzV+YG$(4
* @author GCf3'u
*/ t:|+U:! >
public class CountBean { o9l =Q
private String countType; b`4R`mo
int countId; X CjYm
/** Creates a new instance of CountData */ 2(,
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public CountBean() {} E%f;Z7G
public void setCountType(String countTypes){ rY
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this.countType=countTypes; ; U)a)l'y
} 1lxsj{>U
public void setCountId(int countIds){ q*<Fy4j
this.countId=countIds; NbD"O8dL~E
} 6Q&*V7EO
public String getCountType(){ y5X HJUTu
return countType; =-ky%3:`@
} <By6%<JTn
public int getCountId(){ :?Xd&u0){
return countId; 7VF^&6
} \~(ww3e
} H?dmNwkPY
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CountCache.java 6~
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/* Z=ayVsJ3
* CountCache.java 5aF03+ko
* ,1\nd{
* Created on 2007年1月1日, 下午5:01 vZdn
* CvCk#:@HM
* To change this template, choose Tools | Options and locate the template under Cmq.V@
* the Source Creation and Management node. Right-click the template and choose AC=/BU3<yc
* Open. You can then make changes to the template in the Source Editor. RP2MtP"M
*/ +fgF &.
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package com.tot.count; <p48?+K9
import java.util.*; ~zklrBn&
/** y\'t{>U/
* UF[2Rb8?
* @author sckyG
*/ 58H [sM4>
public class CountCache { ^y?7B_%:B#
public static LinkedList list=new LinkedList(); vrtK~5K
/** Creates a new instance of CountCache */ %$b)l?!
public CountCache() {} k,L ,
public static void add(CountBean cb){
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if(cb!=null){ [69[Ct
list.add(cb); \#(cI
} ;&2J9
} n7RswX
} >IW0YIQy,
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CountControl.java Wgl7)Xk.)
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/* i$)`U]
* CountThread.java KzRw)P
* [sC]<2 r
* Created on 2007年1月1日, 下午4:57 {Gnji] v
* w][1C\8m
* To change this template, choose Tools | Options and locate the template under ckqU2ETpD}
* the Source Creation and Management node. Right-click the template and choose G?LPj*=$?
* Open. You can then make changes to the template in the Source Editor. %}+!%A.3
*/ 8K!
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package com.tot.count; ^h+<Q%'a'
import tot.db.DBUtils; 10v4k<xb
import java.sql.*; r\y~
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/** oYNP,8r^
* u>Z0ug6x
* @author Epm\=s
*/ $oO9N^6yF
public class CountControl{ fF208A7U
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private static long lastExecuteTime=0;//上次更新时间 .:tAZZ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 )5Ddvz>+
/** Creates a new instance of CountThread */ tT}*%A
public CountControl() {} AL/q6PWi
public synchronized void executeUpdate(){ iH& Izv
Connection conn=null; =T)4Oziks
PreparedStatement ps=null; 4@PH5z
try{ bk E4{P"
conn = DBUtils.getConnection(); }2Y:#{m
conn.setAutoCommit(false); xrX^";}j
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 5;+OpB
for(int i=0;i<CountCache.list.size();i++){ B\a-Q,Wf
CountBean cb=(CountBean)CountCache.list.getFirst(); &?mH[rG"
CountCache.list.removeFirst(); BN&^$1F((
ps.setInt(1, cb.getCountId()); t\nYUL-H
ps.executeUpdate();⑴ ?Kw~O"L8
//ps.addBatch();⑵ B./Lp_QK
}
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//int [] counts = ps.executeBatch();⑶ Hm|8ydNs
conn.commit(); 0c4H2RW
}catch(Exception e){ i]8HzKuiW
e.printStackTrace(); Rh-e
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} finally{ !/G2vF"
try{ `;-K/)/x
if(ps!=null) { 7aVQp3<
ps.clearParameters(); 1hj']#vBu
ps.close(); 4I7}
ps=null; 1u&}Lq(
} &MnS(
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}catch(SQLException e){} >3V{I'^^-
DBUtils.closeConnection(conn); $:V'+s4o
} h#9X0u7j
} [z$th
public long getLast(){ u1F@VV{
return lastExecuteTime; q"OvuHBSOn
} G2Eke;
public void run(){ 59:Xu%Hp
long now = System.currentTimeMillis(); 'Z#8]YP`
if ((now - lastExecuteTime) > executeSep) { ~"89NVk"
//System.out.print("lastExecuteTime:"+lastExecuteTime); (]0JI1
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//System.out.print(" now:"+now+"\n"); 8^CdE*a
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 8KRm>-H)
lastExecuteTime=now; {)]5o| Hx
executeUpdate(); |Id0+-V
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}
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else{ h.@5vhD
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Q?KWiFA}'
} L.XGD|m
} x5vvY
} >%k:++b{
//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 _|`~CLE[
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类写好了,下面是在JSP中如下调用。 ]NS{q85
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<% e;9Z/);#s
CountBean cb=new CountBean(); }p 0\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); HV@C@wmg
CountCache.add(cb); Su99A. w
out.print(CountCache.list.size()+"<br>"); coq7La[
CountControl c=new CountControl(); ?yop#tjCbY
c.run(); !, Y1FC
out.print(CountCache.list.size()+"<br>"); '{+5+ J
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