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: S '(K
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CountBean.java Mq Q'Kjo
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/* 3\Tqs
* CountData.java 3(
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* s#4Q?<65u
* Created on 2007年1月1日, 下午4:44 %j.
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* g..&x]aS(
* To change this template, choose Tools | Options and locate the template under G"|c_qX
* the Source Creation and Management node. Right-click the template and choose v&3 Oc
* Open. You can then make changes to the template in the Source Editor. 9FcH\2J
*/ ()ZP=\L
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package com.tot.count; ?!;i/h*{
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/** B"3uuk8
* 8umW>
* @author 8!|LJI
*/ !D~\uW1b
public class CountBean { z *~rd2
private String countType; +OeoA{-W
int countId; Jie=/:&
/** Creates a new instance of CountData */ #]}]ZE
public CountBean() {} B]wfDUG
public void setCountType(String countTypes){ dz,4);Mg
this.countType=countTypes; wak`Jte=}m
} E-L>.tD
public void setCountId(int countIds){ KF}_|~~T
this.countId=countIds; ?,oE_H
} o)sX?IiC
public String getCountType(){ h{.x:pPXy
return countType; .&;:X )
} GN=-dLN
public int getCountId(){ 1(vcM
return countId; nV>=n,+s"
} 0ra+MQBg
} RWdx)qj{
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CountCache.java >gZ"^iW
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/* TSKR~3D#
* CountCache.java 4mwLlYZ
* 5@yBUwMSj
* Created on 2007年1月1日, 下午5:01 [9,34/i
* N51WY7
* To change this template, choose Tools | Options and locate the template under .v[!_bk8C
* the Source Creation and Management node. Right-click the template and choose K(heeZUt
* Open. You can then make changes to the template in the Source Editor. [5wU0~>'
*/ ucX!6)Op
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package com.tot.count; QR(j7>+J^
import java.util.*; <~P([5
/** 3Ss)i7
* ,Lr}P
* @author TF-a1z
*/ mExJ--}
public class CountCache { ~NBlJULS
public static LinkedList list=new LinkedList(); #waK^B)<a
/** Creates a new instance of CountCache */ f (ug3(j
public CountCache() {} =:(<lKf,<F
public static void add(CountBean cb){ Azag*M?
if(cb!=null){ G[s/M\l
list.add(cb); n*y@3.
} -|(
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} ggHz-oNY
} ](SqLTB+?
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CountControl.java GpGq' 8|(
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/* >IEc4
* CountThread.java _2rxDd1#.
* ;0;5+ J7
* Created on 2007年1月1日, 下午4:57 v0,&wdi
* e|Mw9DIW
* To change this template, choose Tools | Options and locate the template under $X]Z-RCK3
* the Source Creation and Management node. Right-click the template and choose cPg$*,]
* Open. You can then make changes to the template in the Source Editor. 7&*d]#&~j
*/ 7U`8W\-
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package com.tot.count; V<0J j
import tot.db.DBUtils; 7!('+x(>
import java.sql.*; lCK|PY*
/** 4<y|SI!
* mcLxX'c6<h
* @author %nT &
*/ YA*E93 J0
public class CountControl{ 28=L9q
private static long lastExecuteTime=0;//上次更新时间 >|_B=<!99W
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4 ky/a1y-
/** Creates a new instance of CountThread */ EV|L~^Q
public CountControl() {} kd+tD!:F(
public synchronized void executeUpdate(){ y3!#*NU
Connection conn=null; mFJb9,
PreparedStatement ps=null; :B1a2Y^"
try{ S<nbNSu6+
conn = DBUtils.getConnection(); ah|`),o(k
conn.setAutoCommit(false); X:d[eAu0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Qm2(Z8Gh
for(int i=0;i<CountCache.list.size();i++){ <hzuPi@
CountBean cb=(CountBean)CountCache.list.getFirst(); A]AM|2 D
CountCache.list.removeFirst(); D[bPm:\0M
ps.setInt(1, cb.getCountId()); x(bM
ps.executeUpdate();⑴ B6"pw0
//ps.addBatch();⑵ )`-vN^1S-
} of>}fJ_p
//int [] counts = ps.executeBatch();⑶ H'wh0K(
conn.commit(); 6I~{~YvB"
}catch(Exception e){ H <ugc
e.printStackTrace(); k=JT%
} finally{ F >co#
try{ (*dJ
if(ps!=null) { HQtUNtZ
ps.clearParameters(); o!}/&
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ps.close(); r!HB""w
ps=null; o>oZh1/\T,
} .aE%z/@s=
}catch(SQLException e){} >TddKR@C
DBUtils.closeConnection(conn); FaA7m
} GN
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} qwDoYyyu
public long getLast(){ 62{[)jt{
return lastExecuteTime; ?%RR+(2m
} ~.f[K{h8
public void run(){ <]kifiN#
long now = System.currentTimeMillis(); ;+4X<)y*>
if ((now - lastExecuteTime) > executeSep) { u(P;) E"1
//System.out.print("lastExecuteTime:"+lastExecuteTime); rBovC
//System.out.print(" now:"+now+"\n"); <n|.Z-gF\
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Q5pm^X._j
lastExecuteTime=now; jN^09T49
executeUpdate(); ,Z p9,nf
} :R9 DJh\
else{ /7-qb^V
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); NzuH&o][
} :h)A/k_
} @AAkEWo)_
} Mq2[^l!qu
//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 Trwk9 +
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类写好了,下面是在JSP中如下调用。 et0yS%7+?@
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<% rkC6-9V
CountBean cb=new CountBean(); P
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); AC9#!#
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CountCache.add(cb); {_5PN^J
out.print(CountCache.list.size()+"<br>"); DC8,ns]!y
CountControl c=new CountControl(); o= N_0.
c.run(); ,Jh('r7
out.print(CountCache.list.size()+"<br>"); HRZ3}8Qj
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