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: QQN6\(;-
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CountBean.java x?B`p"ifS
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/* G7`mK}J7
* CountData.java wAW{{ p
* 8r"-3<*
* Created on 2007年1月1日, 下午4:44 @8m%*pBg
* %7`eT^
* To change this template, choose Tools | Options and locate the template under {na>)qzKP
* the Source Creation and Management node. Right-click the template and choose VhLfSN>W
* Open. You can then make changes to the template in the Source Editor. q]pHD})O
*/ @|"K"j#
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package com.tot.count; P(I%9
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/** vs+aUT C\
* lY@2$q9BT
* @author `5oXf
*/ 2i#Ekon
public class CountBean { ?o6#i 3k#'
private String countType; 2 f%+1uU
int countId; O>vCi&
/** Creates a new instance of CountData */
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public CountBean() {} ucz~y!4L{
public void setCountType(String countTypes){ vJi<PQ6
this.countType=countTypes; A =Z$H2
} ztHx)
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public void setCountId(int countIds){ 5`e;l$
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this.countId=countIds; ](n)bF+ym
} !PeSnO
public String getCountType(){ qhTVsZ:{C
return countType; _}JMBIq$
} TYR \K
public int getCountId(){ wBw(T1VN
return countId; Iy;"ht6
} 4Ng:7C2
} jHE^d<=O^
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CountCache.java tUOY`]0
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/* Zw{?^6;cS
* CountCache.java GNuIcy
* ~;]zEq-hG
* Created on 2007年1月1日, 下午5:01 TUwX4X6m
* N8kNi4$mp=
* To change this template, choose Tools | Options and locate the template under V'dw=W17V
* the Source Creation and Management node. Right-click the template and choose m##!sF^k~J
* Open. You can then make changes to the template in the Source Editor. 9* 3;v;F
*/ -~JYfj@
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package com.tot.count; HrZX~JnTmf
import java.util.*; SvkCx>6/G
/** nIL67&
* B:UM2Jl
* @author KlS#f
*/ "Vl4=W)u
public class CountCache { :Sd`4"AA
public static LinkedList list=new LinkedList(); sz/^Ie-~
/** Creates a new instance of CountCache */ W?wt$'
public CountCache() {} (`#z@,1
public static void add(CountBean cb){ :t "_I
if(cb!=null){ 9(!AKKrr;
list.add(cb); hP.Km%C)0n
} s3@mk\?qMe
} ]n"RPktx
} "Lk BN0D
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CountControl.java w?8\9\ ;?
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/* B1U!*yzG6
* CountThread.java GNrRc3dr$
* tEo-Mj5:
* Created on 2007年1月1日, 下午4:57 NMhpKno
* rx9y^E5T`;
* To change this template, choose Tools | Options and locate the template under ?>V>6cDQ
* the Source Creation and Management node. Right-click the template and choose YjL'GmL<
* Open. You can then make changes to the template in the Source Editor. v?,@e5GZ
*/ I][&*V1
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package com.tot.count; W)T'?b'.
import tot.db.DBUtils; b]xoXC6@ t
import java.sql.*; KkpbZ7\@
/** #M'V%^x P
* zv;xxAX
* @author [N9yWuc
*/ 0&CXR=U5
public class CountControl{ zv/dj04>
private static long lastExecuteTime=0;//上次更新时间 ]s)Y">6
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 oqbz!dM(Z
/** Creates a new instance of CountThread */ f2M*]{N
public CountControl() {} *2vp2xMA@
public synchronized void executeUpdate(){ ]i0=3H2
Connection conn=null; U~?mW,iRL
PreparedStatement ps=null; 6=,zkU*i^
try{ -$g~,dIwj
conn = DBUtils.getConnection(); xb0,dZb
conn.setAutoCommit(false); #%E^cGfY
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?");
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for(int i=0;i<CountCache.list.size();i++){ 'PFjZGaKR
CountBean cb=(CountBean)CountCache.list.getFirst(); q`L)^In"
CountCache.list.removeFirst(); Qmo}esb'(
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ GRofOJ
//ps.addBatch();⑵ 2&]LZ:(
} )Qe]!$tqfD
//int [] counts = ps.executeBatch();⑶ I
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conn.commit(); 5cU:wc
}catch(Exception e){ Rcw[`q3/
e.printStackTrace(); T!41[vm(
} finally{ Ck%if
try{ BB69U
if(ps!=null) { -}!mi V
ps.clearParameters(); OX]P;#4tU
ps.close(); ^=5y;
ps=null; :WQlpLn
} ,~1k:>njY~
}catch(SQLException e){} 4J(-~
DBUtils.closeConnection(conn); Q/4ICgo4
} &)||~
} cbm;45 L|
public long getLast(){ oUN\tOiS+
return lastExecuteTime; "sDs[Lcq
} \~Z%}$ =
public void run(){ TKAs@X,t
long now = System.currentTimeMillis(); ^^B_z|;Aa
if ((now - lastExecuteTime) > executeSep) { 3)?WSOsL:
//System.out.print("lastExecuteTime:"+lastExecuteTime); Z^4+ 88
//System.out.print(" now:"+now+"\n"); +O9x8OPHW
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ZbdGI@
lastExecuteTime=now; >D~8iuy]8.
executeUpdate(); |%F4`gz8KP
} 7D:rq 8$\
else{ C^B$_?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); +0Q +0:
} kb/BEJ
} #wRhR>6
} _TsN%)m
//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 |Z2"pV
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类写好了,下面是在JSP中如下调用。 fvi0gE@bd
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<% Y[}A4`
CountBean cb=new CountBean(); * O?Yp%5NH
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Q#qfuwz
CountCache.add(cb); u'_}4qhCC;
out.print(CountCache.list.size()+"<br>"); }Kp<w,
CountControl c=new CountControl(); GQA\JYw|oY
c.run(); rrj.]^E_~
out.print(CountCache.list.size()+"<br>"); m}RZ)c
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