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: ciHTnC
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CountBean.java }&ew}'*9)
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/* dZ,7q_r,~
* CountData.java tr
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* N:^4OnVR
* Created on 2007年1月1日, 下午4:44 00W_XhJ
* <1V>0[[e
* To change this template, choose Tools | Options and locate the template under zS\m8[+]
* the Source Creation and Management node. Right-click the template and choose u7wZPIC{_
* Open. You can then make changes to the template in the Source Editor. }
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*/ IxlPpS9Wx
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package com.tot.count; 2zjY|g/
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/** HRd02tah
* :OaGdL
* @author ]_y;Igaj
*/ &M\qVL%w
public class CountBean { Wu?[1L:x
private String countType; h=cA]^:=
int countId; a'G[!"
/** Creates a new instance of CountData */ YBk* CW9
public CountBean() {} uvD*]zX
public void setCountType(String countTypes){ Mb%[Qp60
this.countType=countTypes; w^$$'5=
} dfeN_0`-
public void setCountId(int countIds){ B<!wh
this.countId=countIds; 1N8YD .3
} BGT`) WP
public String getCountType(){ SkXx:@
return countType; i;+<5_
} i\L7z)u
public int getCountId(){ M
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return countId; G>^ _&(c@2
} 7
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} n22OPvp
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CountCache.java 7mS_Cz+cB
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/* ubi6=
* CountCache.java CYk"
* ?rwHkPJ{*
* Created on 2007年1月1日, 下午5:01 wMiRN2\^
* zL:k(7E
* To change this template, choose Tools | Options and locate the template under |VX0o2
* the Source Creation and Management node. Right-click the template and choose H`U>ZJ.
* Open. You can then make changes to the template in the Source Editor. 6FI`0j=~
*/ /%^^hr
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package com.tot.count; O6!:Qd
import java.util.*; m3b?f B
/** 1b"3]?
* 3rv~r0
* @author 3n TpL#
*/ `X wKCI
public class CountCache { +?[iB"F
public static LinkedList list=new LinkedList(); v.]W{~PI2V
/** Creates a new instance of CountCache */ htqC~B{1E
public CountCache() {} .`N&,&H
public static void add(CountBean cb){ I*
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if(cb!=null){ yi1V \8DC
list.add(cb); fL R.2vJ
} U[l{cRT
} cU=/X{&Om
} (@u"
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CountControl.java a`QKNrA2
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/* 2k""/xMF'
* CountThread.java cX-)]D
* g(zoN0~
* Created on 2007年1月1日, 下午4:57 WO6; K]
* T_?,?
* To change this template, choose Tools | Options and locate the template under ;!N_8{
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* the Source Creation and Management node. Right-click the template and choose q"^T}d d,
* Open. You can then make changes to the template in the Source Editor. V}"w8i+D?
*/ >!2d77I
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package com.tot.count; 5},kXXN{+
import tot.db.DBUtils; \wo'XF3:
import java.sql.*; ~bk+JK- >
/** W(UrG]J*l
* V4
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* @author |zSoA=7?
*/ %L;'C
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public class CountControl{ <q#/z&F!
private static long lastExecuteTime=0;//上次更新时间 ?f[U8S}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 O0#9D'{
/** Creates a new instance of CountThread */ ~f>km|Q{u
public CountControl() {} G-Ju`.
public synchronized void executeUpdate(){ (&Z`P
Connection conn=null; -7l)mk
PreparedStatement ps=null; &8wluOs/5
try{ 3sq(FsT
conn = DBUtils.getConnection(); *6%r2l'kZ
conn.setAutoCommit(false); '@+a]kCMev
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;;l-E>X0
for(int i=0;i<CountCache.list.size();i++){ |yow(2(F@
CountBean cb=(CountBean)CountCache.list.getFirst(); <swYo<?J#
CountCache.list.removeFirst(); [6t!}q
ps.setInt(1, cb.getCountId()); |#!P!p}
ps.executeUpdate();⑴ ? v2JuhRe
//ps.addBatch();⑵ !NFP=m1
} 4
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//int [] counts = ps.executeBatch();⑶ 0?nm`9v6
conn.commit(); `JL&x|q o
}catch(Exception e){ s\dF7/b
e.printStackTrace(); ;X3bgA']
} finally{ J~vK`+Zs
try{ !>5!Fb=Sy
if(ps!=null) { u0& dDZ
ps.clearParameters(); i^'Uod0d.
ps.close(); Fps.Fhm
ps=null; SLG3u;Ab
} F[SYs/M
}catch(SQLException e){} HJu;4O($
DBUtils.closeConnection(conn); +p:@,_
} p94 w0_m@|
} Pa!r*(M)C
public long getLast(){ K+_$
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return lastExecuteTime; O.8{c;
} #e8NF,H5
public void run(){ KzC`*U[
long now = System.currentTimeMillis(); [8QE}TFic
if ((now - lastExecuteTime) > executeSep) { pP6pn~}
//System.out.print("lastExecuteTime:"+lastExecuteTime); W=T}hA#`
//System.out.print(" now:"+now+"\n"); Eo }mSd
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); xc+h
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lastExecuteTime=now; F$Q@UVA
executeUpdate(); u*$ 1e
} C}{$'#DV2
else{ 2x7%6'
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); B3^4,'
} ES#K'Lf
} }TCOm_Y/qL
} SrVJ Q~:>
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 `<L6Q2Y>j
{
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类写好了,下面是在JSP中如下调用。 ~^Y(f'{
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<% {s=$.Kg
CountBean cb=new CountBean(); Rg6e7JVu
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8HyK;+ZkVd
CountCache.add(cb); ei8OLcw:x
out.print(CountCache.list.size()+"<br>"); 85fBKpEe
CountControl c=new CountControl(); wb
}W;C@
c.run(); x-_!I>l&
out.print(CountCache.list.size()+"<br>"); kOGpe'bV
%>