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: \|M[W~8
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CountBean.java _u6MSRX[6$
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/* RUVrX`u*(
* CountData.java <p2\;\?4z
* l7IF9b$c
* Created on 2007年1月1日, 下午4:44 MIWc
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* >xsY"N&1i'
* To change this template, choose Tools | Options and locate the template under s|TO9N)pO
* the Source Creation and Management node. Right-click the template and choose }"v#_vJfz7
* Open. You can then make changes to the template in the Source Editor. >}JEX]V
*/ }LLQ+
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package com.tot.count; 4nh0bI N1
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/** Q|2*V1"r<2
* [6/8O
* @author NZFUC D)
*/ :()K2<E
public class CountBean { OIjG`~Rx
private String countType; L&uPNcZ`-
int countId; _?$w8 S%
/** Creates a new instance of CountData */ 0(&RmR
public CountBean() {} v!3Oq.ot
public void setCountType(String countTypes){ @uG/2'B(
this.countType=countTypes; c%+uji6
} R9QW%!:,\2
public void setCountId(int countIds){ d5R2J:dI
this.countId=countIds; h%v qt~0
} mC?}:WM@
public String getCountType(){ L;+e)I]
return countType; CUBL/U\=
} F6:LH,~8
public int getCountId(){ jyidNPLm4
return countId; t2rZ%[O
} r@wE?hK
} %*IH~/Ld;]
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CountCache.java }h8U.k?v
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/* ZU2D.Kf_:
* CountCache.java wnQi5P+
* \]\ h,Y8
* Created on 2007年1月1日, 下午5:01 Z^mQb2e.
* /BhP`a%2Q
* To change this template, choose Tools | Options and locate the template under ~SsfkM"
* the Source Creation and Management node. Right-click the template and choose |t;Ktl
* Open. You can then make changes to the template in the Source Editor. T|
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*/ rL?{+S]&^)
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package com.tot.count; q~*|Wd'&
import java.util.*; o? K>ji!
/** ]"j%:fr
* w6^TwjjZ$
* @author (Fq]y5
*/ oU*e=uehj
public class CountCache { Y ._Om}H
public static LinkedList list=new LinkedList(); ,jD-fL/:
/** Creates a new instance of CountCache */ k
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public CountCache() {} r|/9'{!
public static void add(CountBean cb){ Q
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if(cb!=null){ XjxI@VXzUV
list.add(cb); zgn`@y2
} (IA:4E}
} k RSY;V
} BV\~Dm]"
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CountControl.java 2|`Mb~E;
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/* n^l5M^.
* CountThread.java I+jc
* |O"Pb`V+
* Created on 2007年1月1日, 下午4:57 vSH-hAk
* yHZ&5
* To change this template, choose Tools | Options and locate the template under Wv,?xm
* the Source Creation and Management node. Right-click the template and choose PMvm4<
* Open. You can then make changes to the template in the Source Editor. RL/5o"
*/ x_/H
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package com.tot.count; zW. Ltz
import tot.db.DBUtils; y\dx \
import java.sql.*; &hZ6CV{
/** zhyf}Ta'
* 2j1HN
* @author 4e?c W&
*/ :&E~~EUW
public class CountControl{ eQqCRXx
private static long lastExecuteTime=0;//上次更新时间 VjZb\
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #ZHKq7
/** Creates a new instance of CountThread */ 6r[pOl:
public CountControl() {} e%0IEX
public synchronized void executeUpdate(){ _LWMz=U=J/
Connection conn=null; 6QP T
PreparedStatement ps=null; B>cx[.#!
try{ \D#+0
conn = DBUtils.getConnection(); 8%MF<
conn.setAutoCommit(false); N;=J)b|9
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); I Qmlmu
for(int i=0;i<CountCache.list.size();i++){ 8. %g&%S
CountBean cb=(CountBean)CountCache.list.getFirst(); u(ETc*D]
CountCache.list.removeFirst(); /~?[70B}E
ps.setInt(1, cb.getCountId()); yV&]i-ey
ps.executeUpdate();⑴ NxFCVqGb
//ps.addBatch();⑵ qa6HwlC1
} V{}TG]
//int [] counts = ps.executeBatch();⑶ F0kQ/x
conn.commit(); +5kQ;D{+
}catch(Exception e){ >9<rc[
e.printStackTrace(); XqcNFSo)
} finally{ Jr>Nc}!U
try{ ^{E_fQJX
if(ps!=null) { f
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ps.clearParameters(); s(MdjWw
ps.close(); 90H/Txq
ps=null; ;BHIss7
} \z.p [;'ir
}catch(SQLException e){} LXR>M>a`
DBUtils.closeConnection(conn); -,$:^4
} Y)M-?|4
} Ow-;WO_HQ
public long getLast(){ wMM1Q/-#
return lastExecuteTime; a4q02 cV
} &kH7_Lz
public void run(){ oL9ELtb]s
long now = System.currentTimeMillis(); -^rdB6O6j
if ((now - lastExecuteTime) > executeSep) { JNu+e#.Y
//System.out.print("lastExecuteTime:"+lastExecuteTime); dcE(uf
//System.out.print(" now:"+now+"\n"); `_J>R
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); q1/ mp){
lastExecuteTime=now; ;Z,l};b
executeUpdate(); MA7&fNjB
} #vPk
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else{ T7M];@q
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); obgO-d9l
}
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} X:
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} Maiy d
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 a]I~.$G
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类写好了,下面是在JSP中如下调用。 C"h7'+Kw
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<% _IvqZ/6Y(
CountBean cb=new CountBean(); cZw_^@!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 2d&HSW
CountCache.add(cb); >R\!Qk
out.print(CountCache.list.size()+"<br>"); 9*CRMkPrd
CountControl c=new CountControl(); Z>W&vDeuN
c.run(); A5G@u}YS5
out.print(CountCache.list.size()+"<br>"); Ek '%%%
%>