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: @~4Q\^;NX
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CountBean.java =@98Gl9!
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/* 7J
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* CountData.java `zr%+
* mkA1Sh{hX>
* Created on 2007年1月1日, 下午4:44 ]h(}%fk_
* + _=&7
* To change this template, choose Tools | Options and locate the template under ?2Q9z-$
* the Source Creation and Management node. Right-click the template and choose 3DNw=Ic0k
* Open. You can then make changes to the template in the Source Editor. ~Rs_ep'+Q2
*/ YbMeSU/sX
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package com.tot.count; \DP*?D_}?
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/**
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* ~16QdwK
* @author ~!*xi
*/ K`=O!;
public class CountBean { *
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private String countType;
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int countId; ]9xuLJ)
/** Creates a new instance of CountData */ fS08q9,S /
public CountBean() {} xc%\%8C}
public void setCountType(String countTypes){ K;%P_f/KJP
this.countType=countTypes; ^4Nk13
} JArSJ:}
public void setCountId(int countIds){ `>M-J-J
this.countId=countIds; Y\7>>?
} <ptgFR+
public String getCountType(){ TU6e,G|t
return countType; o:H^
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} {K\l3_=5qb
public int getCountId(){ 3F5Y#[L`
return countId; [>5<&[A
} Z(fXN$
} 3;M7^DM
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CountCache.java #6< X
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/* q^:>sfd
* CountCache.java mR3)$!
* m3Mo2};?
* Created on 2007年1月1日, 下午5:01 VMry$
* 2K^D%U
* To change this template, choose Tools | Options and locate the template under W[pOLc-
* the Source Creation and Management node. Right-click the template and choose ]_Cm 5Z7
* Open. You can then make changes to the template in the Source Editor. \rXmWzl{
*/ D?+\"lI
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package com.tot.count; =?o, ' n0
import java.util.*; HGuU6@~hu
/** M^q< qS>d
* ~UrKyA
* @author |u r/6{Oj1
*/ Wo&WO
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public class CountCache { glMYEGz6p
public static LinkedList list=new LinkedList(); C5}c?=#bdf
/** Creates a new instance of CountCache */ ChvSUaCS
public CountCache() {} H1?t2\V4
public static void add(CountBean cb){ K|i:tHF]@
if(cb!=null){ 06ndW9>wD)
list.add(cb); W''%{A/'
} Xk9mJ]31LC
} wM$N#K@
} g=Gd|
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CountControl.java <WXGDCj
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/* &a;{ed1B
* CountThread.java cTC -cgp
* FEC`dSTI
* Created on 2007年1月1日, 下午4:57 (/mR
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*
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* To change this template, choose Tools | Options and locate the template under Tu!2lHK;
* the Source Creation and Management node. Right-click the template and choose *5|;eN
* Open. You can then make changes to the template in the Source Editor. .<m${yU{3
*/ `w&A;fR!H
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package com.tot.count; Kw%to9eh)
import tot.db.DBUtils; r\PO?1
import java.sql.*; FTF`-}Hz
/** YkN0,6
* W
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* @author ;JuBybJb
*/ J-UqH3({Z,
public class CountControl{ {yzo#"4Oy
private static long lastExecuteTime=0;//上次更新时间 1"\^@qRv#
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0hNgr'
/** Creates a new instance of CountThread */ /` ;rlH*
public CountControl() {} vVbBg; {
public synchronized void executeUpdate(){ @u>:(9bp
Connection conn=null; U/#X,Bi~
PreparedStatement ps=null; #+"1">l
try{ o?{-K-'B$
conn = DBUtils.getConnection(); 5i0vli/L
conn.setAutoCommit(false); YHp]O+c
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); g1H$wU3eu
for(int i=0;i<CountCache.list.size();i++){ v:IpZ;^
CountBean cb=(CountBean)CountCache.list.getFirst(); <"hq}B
CountCache.list.removeFirst(); 5y~Srb?2
ps.setInt(1, cb.getCountId()); qNuBK6E#4
ps.executeUpdate();⑴ tqFE>ojlI
//ps.addBatch();⑵ 3/{,}F$
}
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//int [] counts = ps.executeBatch();⑶ u2E}DhV
conn.commit(); D_Zt:tzO
}catch(Exception e){ D[
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e.printStackTrace(); 6no&2a|D
} finally{ 0woLB#v9
try{ K'c[r0Ew
if(ps!=null) { 8b[<:{[YB
ps.clearParameters(); c }7gHud
ps.close(); /tG[pg{[
ps=null; ROr|n]aJj
} ts/Ha*h
}catch(SQLException e){} WB.w3w[f
DBUtils.closeConnection(conn); 7PbwCRg
} $/kZKoF{f
} 7Tc^}Q
public long getLast(){ "=Cjm`9~j
return lastExecuteTime; -4v2]
} yIu_DFq%
public void run(){ `sLD>@m
long now = System.currentTimeMillis(); &9ERlZ(A
if ((now - lastExecuteTime) > executeSep) { b?j\YX[e
//System.out.print("lastExecuteTime:"+lastExecuteTime); |Sv}/P-
//System.out.print(" now:"+now+"\n"); ROJ=ZYof
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); @Yw>s9X
lastExecuteTime=now; qK)T#sh
executeUpdate(); *o=[p2d"X
} T2_b5j3i
else{ Ce:w^P+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Z_4|L+i<{
} eyuQ}R
} wln"g,ct
} VKcVwq
//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 |~B` [p]5H
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类写好了,下面是在JSP中如下调用。 i|xC#hV
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<% AEd9H
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CountBean cb=new CountBean(); nP0rg
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |`' WEe2
CountCache.add(cb); _ZE&W
out.print(CountCache.list.size()+"<br>"); bb}Fu/S
CountControl c=new CountControl(); _Mi*Fvj
c.run(); 'yR\%#s6
out.print(CountCache.list.size()+"<br>"); sn8l3h)
%>