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: Hr=|xw8.
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CountBean.java ,j{tGj_
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/* Q3hSWXq'
* CountData.java ]5@n`;.
* OpazWcMoo
* Created on 2007年1月1日, 下午4:44 +VQD'
* :Hb`vH3x
* To change this template, choose Tools | Options and locate the template under QoUdTIIL
* the Source Creation and Management node. Right-click the template and choose _R]0S
* Open. You can then make changes to the template in the Source Editor. }M(xN6E
*/ qGhg?u"n:
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package com.tot.count; i/C%
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/** )RTWt`
* &ID! lEd
* @author 78*8-
*/ sMVk]Mb
public class CountBean { 9fs-|E[5
private String countType; Vp1ct06^
int countId; a6xo U;T
/** Creates a new instance of CountData */ C6F7,v62
public CountBean() {} %t6-wWM97
public void setCountType(String countTypes){ "doiD=b
this.countType=countTypes; dPpJDY0
} [\eVX`it
public void setCountId(int countIds){ h|PC?@jp
this.countId=countIds; cR!M{U.q
} Hn(Eut7%
public String getCountType(){ #Vmf
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return countType; V'RbTFb9Z
} \K"7U
public int getCountId(){ ZDL1H3;R
return countId; +w.$"dF!
} XUVj<U
} 31 <0Nw;l
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CountCache.java N<b2xT
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/* #^]vhnbN
* CountCache.java _OjZ>j<B.
* Xm|~1 k_3
* Created on 2007年1月1日, 下午5:01 ){)-}M
* =Yl ea,S
* To change this template, choose Tools | Options and locate the template under dR_6j}
* the Source Creation and Management node. Right-click the template and choose (_@]-
* Open. You can then make changes to the template in the Source Editor. cK\
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*/ |,=^P`#%
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package com.tot.count; 1,h:|
import java.util.*; X=1o$:7
/** N2HD=[*cr
* __7}4mA
* @author .hG*mXw>
*/ )qMbk7:v\
public class CountCache { l(87s^_
public static LinkedList list=new LinkedList(); ?aWVfX!+G5
/** Creates a new instance of CountCache */ EFx>Hu/[G
public CountCache() {} 'nM4t
public static void add(CountBean cb){ Ye$j43b
if(cb!=null){ <b *sn]l
list.add(cb); 9M($_2,44
} :2M&C+f[
} 'Nt)7U>oC9
} bW!
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CountControl.java vR!g1gI23
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/* yZ[g2*1L
* CountThread.java N>*+Wg$Ne
* U/kQw rM
* Created on 2007年1月1日, 下午4:57 zdU46|!u
* JN9>nC!Zy_
* To change this template, choose Tools | Options and locate the template under LWTPNp:"{w
* the Source Creation and Management node. Right-click the template and choose z7AWWr=H
* Open. You can then make changes to the template in the Source Editor. flC%<V%'-
*/ =&pLlG
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package com.tot.count; 3+uL@LXd
import tot.db.DBUtils; *-Yw%uR
import java.sql.*; T_D] rMl
/** =$)M-;6
* \$.{*f
* @author
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*/ N%Ta.`r
public class CountControl{ d,l?{Ln
private static long lastExecuteTime=0;//上次更新时间 *5k40?w
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ]OdZlZBsJ
/** Creates a new instance of CountThread */ 4c(Em+4
public CountControl() {} I-g/)2
public synchronized void executeUpdate(){ $F#
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Connection conn=null; $fg@g7_:
PreparedStatement ps=null; 8Vj'&UY
try{ 7p2xst
conn = DBUtils.getConnection(); I_z(ft.
conn.setAutoCommit(false); 7_ayn#;y
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); p)iEwl}!j
for(int i=0;i<CountCache.list.size();i++){ MomHSv Q\
CountBean cb=(CountBean)CountCache.list.getFirst(); 7p Y :.iVO
CountCache.list.removeFirst(); `ROHB@-
ps.setInt(1, cb.getCountId()); 6uo;4}0
ps.executeUpdate();⑴ n }A!aC
//ps.addBatch();⑵ Mhti
} 300w\9fn&
//int [] counts = ps.executeBatch();⑶ VSDua.
conn.commit(); R^/SBrWve
}catch(Exception e){ 0stc$~~v
e.printStackTrace();
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} finally{ #L+:MA7H
try{ h,m 90Hd+
if(ps!=null) { b \`S[
ps.clearParameters();
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ps.close(); 9>9EZ?4m
ps=null; fM"*;LN!N
} P* `*^r3
}catch(SQLException e){} 1,;X4/*
DBUtils.closeConnection(conn); jmkOu5@
} dV'EiNpf
} *QiQ,~Ep
public long getLast(){ rfEWh
Vy(}
return lastExecuteTime; -GCo`PR?b
} / 'qoKof
public void run(){ 9)'f)60^
long now = System.currentTimeMillis(); lh"*$.j-
if ((now - lastExecuteTime) > executeSep) { c'eZ-\d{
//System.out.print("lastExecuteTime:"+lastExecuteTime); _;;Zz&c
//System.out.print(" now:"+now+"\n"); %;dj6):@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); m]AT-]*f
lastExecuteTime=now; edq,:
executeUpdate(); OQKeU0v
} rT/r"vr
else{ f2;.He
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); _i+@HXR &
} 8;DDCop 8L
} MHK|\Z&e7
} y')OmR2h
//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 ,u2Qkw
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类写好了,下面是在JSP中如下调用。 qtZ?
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<% {k)gDJU
CountBean cb=new CountBean(); \\FT.e6
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ;cI*"-I:F
CountCache.add(cb); \4>,L_O
out.print(CountCache.list.size()+"<br>"); =otO@22Np
CountControl c=new CountControl(); , [|aWT%9
c.run(); z6ObX
out.print(CountCache.list.size()+"<br>"); Ck
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%>