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: Wt*&_+ae
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CountBean.java * _ {w0U)
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/* $yS7u
* CountData.java SRuNt3wW6
* f^z/s6I0
* Created on 2007年1月1日, 下午4:44 f^\qDvPur
* `Hld#+R
* To change this template, choose Tools | Options and locate the template under #Y6'Q8gf
* the Source Creation and Management node. Right-click the template and choose z'GYU=
* Open. You can then make changes to the template in the Source Editor. )>abB?RZ
*/ 794V(;sW,
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package com.tot.count; `],'fT|,S
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/** 9&a&O
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* U2l7@uDr;
* @author Q$r1beA
*/ ! c,=%4Pb
public class CountBean { +MU|XT_5|6
private String countType; gIa/sD2m>
int countId; .cJWYMC
/** Creates a new instance of CountData */ tp"dho
public CountBean() {} kW=g:m
public void setCountType(String countTypes){ |>(d^<nR^v
this.countType=countTypes; Q[+&n*
} hqOy*!8'@
public void setCountId(int countIds){ .4DX/~F
this.countId=countIds; s8 S[w
} ocOzQ13@Y
public String getCountType(){ PEqO<a1Z8
return countType; Ln-/
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} z9OhY]PPF
public int getCountId(){ Q[?O+
return countId; NGZEUtj
} "|<6bA
} ?`T<
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CountCache.java {!h|(xqN+
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/* 49.
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* CountCache.java i
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* XwWp4`Fd
* Created on 2007年1月1日, 下午5:01 &-^|n*=g6
* .PjJ g^^
* To change this template, choose Tools | Options and locate the template under hwgLJY?
* the Source Creation and Management node. Right-click the template and choose sDNV_}
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* Open. You can then make changes to the template in the Source Editor. |Yq0zc!
*/ "o"ujQ(v
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package com.tot.count; qIE e7;DO
import java.util.*; 9gFb=&1k
/** LS1r}cl
* sbnNk(XINQ
* @author fT)u`voE,
*/ pe(31%(h
public class CountCache { ,=o)R,[
public static LinkedList list=new LinkedList(); LvP{"K;
/** Creates a new instance of CountCache */ &.XYI3Ab1
public CountCache() {} S-)mv'Al'F
public static void add(CountBean cb){ MR8\'0]
if(cb!=null){ n27df9L
list.add(cb); LObS
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} (Uk1Rt*h
} S<),
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} F<SCW+>z2a
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CountControl.java % H"A%
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/* b(@[Y(_R
* CountThread.java 8Q $fXB
* /JaCbT?*T
* Created on 2007年1月1日, 下午4:57 nsO!
* :|%dV}j
* To change this template, choose Tools | Options and locate the template under &E98&[`7
* the Source Creation and Management node. Right-click the template and choose iq s
* Open. You can then make changes to the template in the Source Editor. "r@f&Ssxb
*/ 8S;]]*cD~
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package com.tot.count; S 6e<2G=O
import tot.db.DBUtils; w[g(8#*
import java.sql.*; w7n6@"q
/** Yt^<^l77D
* 'n'83d)z
* @author (dSf>p r2
*/ 'k|?M
public class CountControl{ {\tHS+]
private static long lastExecuteTime=0;//上次更新时间 vfb~S~|U6g
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 i1ph{;C
/** Creates a new instance of CountThread */ @S#>:o|
public CountControl() {} w h4WII
public synchronized void executeUpdate(){ #ma#oWqF }
Connection conn=null; hD OEJ
PreparedStatement ps=null; K@ZK@++
try{ lZyxJDZ A
conn = DBUtils.getConnection(); vN=bd7^?=
conn.setAutoCommit(false); wSrq?U5q
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); a3o4> 9
for(int i=0;i<CountCache.list.size();i++){ f? sW^d;
CountBean cb=(CountBean)CountCache.list.getFirst(); YyI4T/0s_
CountCache.list.removeFirst(); R-xWZRl>
ps.setInt(1, cb.getCountId()); D9OI",h
ps.executeUpdate();⑴ ,~;_-
//ps.addBatch();⑵ 3hzI6otKS
} dWC[p
//int [] counts = ps.executeBatch();⑶ +q z"+g
conn.commit(); Vf
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}catch(Exception e){ $@8$_g|Wz
e.printStackTrace(); eBZ^YY<*g
} finally{ TF)OBN~/
try{ %m\dNUz4g
if(ps!=null) { -C9_gZ
ps.clearParameters(); t?[|oz:v
ps.close(); JXR_klx
ps=null; ]
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} _O!)aD
}catch(SQLException e){} ZzDE
DBUtils.closeConnection(conn); < 8yv(
} n<C4-'^U[a
} ],rtSUO
public long getLast(){ XwlAW7lU=
return lastExecuteTime; 4H4U
} I+ZK \?Rs
public void run(){ {Vz.|
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long now = System.currentTimeMillis(); -Fcg}\9
if ((now - lastExecuteTime) > executeSep) { j(j o8
//System.out.print("lastExecuteTime:"+lastExecuteTime); R#ayN*
//System.out.print(" now:"+now+"\n"); &<</[h/B/F
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 2l43/aCq
lastExecuteTime=now; 4 z~ fn9g
executeUpdate(); RfP>V/jy5
} fFG, ^;7-O
else{ Qz*!jwg
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Z
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} chjXsq#Q^
} g(d9=xq@k
} _I;+p eq
//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 p"9a`/
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类写好了,下面是在JSP中如下调用。 aL\vQ(1zO
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<% ?2ZggV
CountBean cb=new CountBean(); !mFx= +
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); p7b`Z>}
CountCache.add(cb); 2#z 6= M~A
out.print(CountCache.list.size()+"<br>"); y~)rZ-eSB
CountControl c=new CountControl(); L(tA~Z"k
c.run(); %U]_1"d,<\
out.print(CountCache.list.size()+"<br>"); x <^vJ1
%>