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: 2`-Bs
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CountBean.java 6S{l'!s'
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/* ugBCBr
* CountData.java %
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* 'N(R_q6MW
* Created on 2007年1月1日, 下午4:44 {4PwLCy
* GA.8@3
* To change this template, choose Tools | Options and locate the template under !n%j)`0M
* the Source Creation and Management node. Right-click the template and choose D6Wa.,r
* Open. You can then make changes to the template in the Source Editor. 2&5K.Ui%
*/ H,NF;QPPC
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package com.tot.count; Alq(QDs
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/** L RF103nw
* *NQ/UXE
* @author R|Q?KCI&
*/ H"F29Pu2
public class CountBean { V~ _>U}
private String countType; #LNED)Vg
int countId; e#q}F>/L
/** Creates a new instance of CountData */ *K;~!P
public CountBean() {} -n;}n:wL
public void setCountType(String countTypes){ WY]s |2a
this.countType=countTypes;
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} S8gs-gL#Og
public void setCountId(int countIds){ d d;T-wa}
this.countId=countIds; Xnh8e
} ##ANrG l
public String getCountType(){ i@'dH3-kO
return countType; S]{oPc[7
} K>
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public int getCountId(){ ;n},"&
return countId; FiU#T.`9'
} 3gf1ownC
} Z6m)tZVM
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CountCache.java :v 4]D4\o
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/* WF"k[2
* CountCache.java DV{=n C
* ?X;RLpEc|A
* Created on 2007年1月1日, 下午5:01 [00m/fT6
* ;wD)hNLAvR
* To change this template, choose Tools | Options and locate the template under %XTI-B/K
* the Source Creation and Management node. Right-click the template and choose 2T`!v
* Open. You can then make changes to the template in the Source Editor. yLcEX
*/ rM"l@3hP
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package com.tot.count; 2Rz
import java.util.*; GKCroyor
/** 9!tW.pK5
* \j.:3Xr
* @author @ .KGfNu
*/ FPTK`Gd0
public class CountCache { ?%kV?eu'
public static LinkedList list=new LinkedList(); 8XbT`y
/** Creates a new instance of CountCache */ mVmGg,
public CountCache() {} I2DpRMy
public static void add(CountBean cb){ J8~haim
if(cb!=null){ 9>$p
list.add(cb); -Qe Z#w|
} A\;U3Zu
} .sA.C]f
} O'~+_ykTl
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CountControl.java U;I9 bK8
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/* t:c.LFrF
* CountThread.java /L#?zSt
* mcok/,/
* Created on 2007年1月1日, 下午4:57 L8n|m!MOD
* lRdChoL$2
* To change this template, choose Tools | Options and locate the template under 6zn5UW#q
* the Source Creation and Management node. Right-click the template and choose D#z:()VT(
* Open. You can then make changes to the template in the Source Editor. GJUL$9
*/ FgI3
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package com.tot.count; ?hM64jI|
import tot.db.DBUtils; (I}v[W
import java.sql.*; s(8W_4&'
/** Qei"'~1a
* { "E\Jcjl\
* @author RGX=)
*/ c"xK`%e
public class CountControl{ \(T/O~b2
private static long lastExecuteTime=0;//上次更新时间 ,=N.FS
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Xm2'6f,
/** Creates a new instance of CountThread */ rN{ c7/|
public CountControl() {} 07 $o;W@
public synchronized void executeUpdate(){ #D|p2L$
Connection conn=null; |)G<,FJQE_
PreparedStatement ps=null; Xry47a
)
try{ %07SFu#
conn = DBUtils.getConnection(); l@:0e]8|o
conn.setAutoCommit(false); #89!'W
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Lh<).<S
for(int i=0;i<CountCache.list.size();i++){ 8.~kK<)!
CountBean cb=(CountBean)CountCache.list.getFirst(); yOKI*.}
CountCache.list.removeFirst(); abEmRJTmW
ps.setInt(1, cb.getCountId()); -!9G0h&i|
ps.executeUpdate();⑴ nxHkv`s k
//ps.addBatch();⑵ Y4(
} llsfTrp
//int [] counts = ps.executeBatch();⑶ w`=\5Oa .G
conn.commit(); MJrR[h]
}catch(Exception e){ Ic4H# w
e.printStackTrace(); .>nRzgo
} finally{ 8sCv]|cn
try{ sT' 5%4
if(ps!=null) { ]0\MmAJRn
ps.clearParameters(); VD\=`r)nT
ps.close(); t()c=8qF|u
ps=null; A +)`ZTuO
} v9->nVc-
}catch(SQLException e){} zv"Z DRW
DBUtils.closeConnection(conn); Hq 188<
} T,tdL
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} j8`BdKg
public long getLast(){ u~-8d;+?y
return lastExecuteTime; +2j AC r
} BF <ikilR
public void run(){ {qMIGwu
long now = System.currentTimeMillis(); !?gKqx'T$
if ((now - lastExecuteTime) > executeSep) { SZ$Kz n
//System.out.print("lastExecuteTime:"+lastExecuteTime); *WT`o>
//System.out.print(" now:"+now+"\n"); >dG[G>
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); N.{D$"
lastExecuteTime=now; 6MkP |vr6
executeUpdate(); ;w[0t}dPl
} OydwE
else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -D$8
} m9Hit8f@Q
} #1G:lhkC
} ?K\axf>F
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 @y&bw9\
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类写好了,下面是在JSP中如下调用。 t`mV\)fa
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<%
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CountBean cb=new CountBean(); }AH]
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Z)aUt
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CountCache.add(cb); _f:W?$\ho
out.print(CountCache.list.size()+"<br>"); 3Ims6I]
CountControl c=new CountControl(); #
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c.run(); &pp|U}
out.print(CountCache.list.size()+"<br>"); :[!j?)%>
%>