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: 0~^RHb.NA8
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CountBean.java ud$-A
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/* {XmCG%%L
* CountData.java 4F6aPo2
* tj[E!
* Created on 2007年1月1日, 下午4:44 KRC"3Qt
* znwKwc8,
* To change this template, choose Tools | Options and locate the template under Nb`qM]&
* the Source Creation and Management node. Right-click the template and choose (;},~( 2B
* Open. You can then make changes to the template in the Source Editor. IUFc_uL@\
*/ @nY]S\if
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package com.tot.count; ~EPVu
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/** \xCCJWek
* ~!
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* @author Ct w <-'
*/ bTaKB-
public class CountBean { gYc]z5`
private String countType; Oti*"dV\::
int countId; m"iA#3l*=
/** Creates a new instance of CountData */ hDW!pnj1
public CountBean() {} |j`73@6
public void setCountType(String countTypes){ c
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this.countType=countTypes; VIP7j(#t_g
} `Zm6e!dH-
public void setCountId(int countIds){ 1^}I?PbqV
this.countId=countIds; Ec@n<KK#
} 2+
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public String getCountType(){ 6p)AQTh>
return countType; Q,&Li+u|
} MxIa,M<
public int getCountId(){ 9_?xAJ
return countId; "+ou!YK+
} ^Fco'nlM
} 0- )K_JV
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CountCache.java -V|"T+U
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/* 0
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* CountCache.java o3 fc -
* "s(~k
* Created on 2007年1月1日, 下午5:01 :eVZ5?F
* }|kFHodo
* To change this template, choose Tools | Options and locate the template under k||t<&`Ze
* the Source Creation and Management node. Right-click the template and choose S'jg#*$
* Open. You can then make changes to the template in the Source Editor. T$xBH
*/ ;/j2(O^
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package com.tot.count; E[]5Od5#
import java.util.*; FQDf?d5
/** [X.bR$>
* vA1YyaB
* @author 3 !@
*/ "d_wu#fO)
public class CountCache { kt/,& oKI
public static LinkedList list=new LinkedList(); s{Z)<n03
/** Creates a new instance of CountCache */ MY^{[#Q
public CountCache() {} F~mIV;BP
public static void add(CountBean cb){ J,2V&WuV0r
if(cb!=null){ D0r viO
list.add(cb); FPDTw8" B;
} CI'RuR3y]Z
} iAwEnQ3h
} 50^ux:Uv+N
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CountControl.java ]dpL
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/* >.iF,[.[F<
* CountThread.java f~`=I NrU
* Q5+1'mzAB
* Created on 2007年1月1日, 下午4:57 -Uwxmy +
* J?QS7#!%
* To change this template, choose Tools | Options and locate the template under -b(DPte
* the Source Creation and Management node. Right-click the template and choose `@/)S^jBau
* Open. You can then make changes to the template in the Source Editor. HeRi67
*/ L=r*bq
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package com.tot.count; cuhp4!!
import tot.db.DBUtils; \HfAKBT
import java.sql.*; % =^/^[D
/** NBYJ'nA%;f
* ^`&'u_B!+
* @author i}) s4%a
*/ H@Z_P p?
public class CountControl{ /<J(\;Jr6
private static long lastExecuteTime=0;//上次更新时间 !(GyOAb
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 nI\6aG?`
/** Creates a new instance of CountThread */ Y}:~6`-jj
public CountControl() {} k{}> *pCU
public synchronized void executeUpdate(){ 9P?0D
Connection conn=null; pM?;QG;jA
PreparedStatement ps=null; $Habhw
try{ jx: IK
conn = DBUtils.getConnection(); w&p+mJL.
conn.setAutoCommit(false); 3
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 4b8G 1fm
for(int i=0;i<CountCache.list.size();i++){ C0wtMD:G
CountBean cb=(CountBean)CountCache.list.getFirst(); ~]?:v,UIm(
CountCache.list.removeFirst(); #S}orWj
ps.setInt(1, cb.getCountId()); VI0wul~M
ps.executeUpdate();⑴ .uuhoqG0
//ps.addBatch();⑵ >t+U`6xK
}
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//int [] counts = ps.executeBatch();⑶ YV
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conn.commit(); #De>EQ%
}catch(Exception e){ #,%bW[L<N
e.printStackTrace(); ?d7,0Ex
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} finally{ x< A-Ws{^V
try{ -NBVUUAgN
if(ps!=null) { f[@96p?a[
ps.clearParameters(); 36"n7
ps.close(); d*@T30
ps=null; aZOn01v;!&
} |&; ^?M
}catch(SQLException e){} O=B=0
DBUtils.closeConnection(conn); f9.?+.^_
} BI1M(d#1L"
} ,>;21\D
public long getLast(){ aZFpt/.d
return lastExecuteTime; IDohv[#
} *WwM"NFHDd
public void run(){ 3Z!%td5n
long now = System.currentTimeMillis(); !GcBNQ1p+7
if ((now - lastExecuteTime) > executeSep) { k# [!; <
//System.out.print("lastExecuteTime:"+lastExecuteTime); <LHhs<M'
//System.out.print(" now:"+now+"\n"); tW\yt~q,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 4Uy% wB
lastExecuteTime=now; =)a24PDG
executeUpdate(); cS ~OxAS
} ]I?.1X5d0
else{ uO%0rKW
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2|nm> 4
} :gVUk\)
} Vao:9~
} "-~7lY%
//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 d)o5JD/
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类写好了,下面是在JSP中如下调用。 `|dyT6V0I_
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<% ZT0\V
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CountBean cb=new CountBean(); HI.*xkBXl&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 66yw[,Y
CountCache.add(cb); 2~4:rEPJ:
out.print(CountCache.list.size()+"<br>"); AZj&;!}
CountControl c=new CountControl(); }A)\bffH
c.run(); 3BFOZV+
out.print(CountCache.list.size()+"<br>"); 9/ <3mF@E
%>