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: "/Y<G
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CountBean.java 1)$%Jr
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/* ki\B!<uv
* CountData.java TG1P=g5h
* Ba/RO36&c
* Created on 2007年1月1日, 下午4:44 ,%A)"doaG
* bRWIDPh
* To change this template, choose Tools | Options and locate the template under 8V6=i'GK
* the Source Creation and Management node. Right-click the template and choose *%:@
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* Open. You can then make changes to the template in the Source Editor. GHv{
*/ Vd,' s
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package com.tot.count; @'*eC}\E
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/** [-4KY4R
* K'x4l,rq
* @author `q%U{IR
*/ dw~[9oh
public class CountBean { ):3MYSqX
private String countType; *~cqr
int countId; v9u<F6
/** Creates a new instance of CountData */ ERF,tLa!
public CountBean() {} !6M Bxg >
public void setCountType(String countTypes){ ar Q)%W
this.countType=countTypes; -^yXLa;D
} kB8
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public void setCountId(int countIds){ cC'
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this.countId=countIds; /dLA`=r Zx
} $K})Q3FNi
public String getCountType(){ E(_KN[}S
return countType; K]X`sH:
} (4~X}:
public int getCountId(){ Mal <iNN
return countId; auRY|j
} /-Wuq`P/ T
} ;> DHD*3X
}<=3W5+
CountCache.java &M[MEO`t8
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/* !K[/L<
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* CountCache.java |8bE9qt.P
* 69Nw/$
* Created on 2007年1月1日, 下午5:01 80|onP\L
* kQLT$8io
* To change this template, choose Tools | Options and locate the template under [9OSpq
* the Source Creation and Management node. Right-click the template and choose 'f*O#&?
* Open. You can then make changes to the template in the Source Editor. fuMN"T 6%+
*/ TtPr)F|
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package com.tot.count; Tp?-*K
import java.util.*; kae2 73"
/** \b$<J.3
* 5X0QxnnV
* @author Z ] '>
*/ r?pZ72q
public class CountCache { |H
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public static LinkedList list=new LinkedList(); I+|uUg5
/** Creates a new instance of CountCache */ JdiP>KXV
public CountCache() {} ZYa\"zp-
public static void add(CountBean cb){ qEQAn/&
if(cb!=null){ b,Ke>.m
list.add(cb); Nt~x&s
} ^LVk5l)\>g
} Um z05*
} ]boE{R!I
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CountControl.java yAG+] r
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/* xIL#h@dz
* CountThread.java 0Gsu
* i6Qb[\;
* Created on 2007年1月1日, 下午4:57 (9]6bd
* zT7"VbP
* To change this template, choose Tools | Options and locate the template under (~&w-w3
* the Source Creation and Management node. Right-click the template and choose O#EqG.L5
* Open. You can then make changes to the template in the Source Editor. :H?f*aw
*/ :3^dF}>
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package com.tot.count; #Ao !>qCE
import tot.db.DBUtils; DtI$9`~
import java.sql.*; `*aBRwvK~
/** Lc]1$
* U;U08/y
* @author rP'AJDuq
*/ O9^T3~x[V
public class CountControl{ d)tiO2W
private static long lastExecuteTime=0;//上次更新时间 HTk\723Rdw
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 >3PMnI
/** Creates a new instance of CountThread */ )3%@9
public CountControl() {} ^ H3m\!h
public synchronized void executeUpdate(){ N*_"8LIfi_
Connection conn=null; >b48>@~bY
PreparedStatement ps=null; 8eJE>g1J
try{ ,q#2:b<E
conn = DBUtils.getConnection(); l^W uS|G[
conn.setAutoCommit(false); ^=+e?F`:{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); YJ,*(A18
for(int i=0;i<CountCache.list.size();i++){ (.?ZKL
CountBean cb=(CountBean)CountCache.list.getFirst(); ubbnFE&PD
CountCache.list.removeFirst(); G;s"h%Xw98
ps.setInt(1, cb.getCountId()); O~PChUU*Y
ps.executeUpdate();⑴ 0Z
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//ps.addBatch();⑵ Vb!O8xV4;+
} c-B/~&
//int [] counts = ps.executeBatch();⑶ R0wf#%97
conn.commit(); oa`#RC8N
}catch(Exception e){ {DwIjy31T
e.printStackTrace(); ?pG/m%[
} finally{ =45W\
try{ .'T 40=7
if(ps!=null) { {kL&Rv%'
ps.clearParameters(); {eQWO.C{
ps.close(); GeV+/^u
ps=null; `/4:I
} uel{`T[S
}catch(SQLException e){} J,5+47b1}R
DBUtils.closeConnection(conn); x[X`a
} $a(`ve|
} 1~\M!SQ)
public long getLast(){ >c~RI7uu
return lastExecuteTime; m`}{V5;
} IQnIaZ
public void run(){ z9DcnAs
long now = System.currentTimeMillis(); U~H?4Izl=
if ((now - lastExecuteTime) > executeSep) { cWa)#:JOV
//System.out.print("lastExecuteTime:"+lastExecuteTime); U>F{?PReA?
//System.out.print(" now:"+now+"\n"); cyQBqG
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "9XfQ"P
lastExecuteTime=now; Ew$I\j*
executeUpdate(); aG{$Ic
} u9Y3?j,oC
else{ ]
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); U| 5-0 u5
} ,_ .v_
} I ~$1Lu`~
} VhEka#
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 lH2wG2
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类写好了,下面是在JSP中如下调用。 obo&1Uv,/
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<%
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CountBean cb=new CountBean(); 2@khSWV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 4kl Ao$
CountCache.add(cb); X`JVR"=4
out.print(CountCache.list.size()+"<br>"); [4Q"#[V&9
CountControl c=new CountControl(); :O-1rD
c.run(); +L%IG
out.print(CountCache.list.size()+"<br>"); ub K7B |p
%>