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: N_c44[z1
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CountBean.java j?2~6W/[
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/* ""-wM~^D
* CountData.java }YDi/b7
* %)lp]Y33
* Created on 2007年1月1日, 下午4:44 3IMvtg
* [
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* To change this template, choose Tools | Options and locate the template under L0wT :x*
* the Source Creation and Management node. Right-click the template and choose ^o3,YH
* Open. You can then make changes to the template in the Source Editor. eq6O6-
*/ |R9Lben',
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package com.tot.count; e#Cv*i_<
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/** Pzso^^g
* d)AYY}pw
* @author }:#WjH^
*/ LL( xi )
public class CountBean { )=~&l={T
private String countType; NpH8=H9
int countId; 0zr27ko
/** Creates a new instance of CountData */ x0<;Rm [u=
public CountBean() {} .#yg=t1C
public void setCountType(String countTypes){ EsGu#lD2
this.countType=countTypes; lMY\8eobcB
} '3>;8(sl
public void setCountId(int countIds){ XKjrS
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this.countId=countIds; #%E`~&[
} *E/Bfp1LIe
public String getCountType(){ [9">}l
return countType; dOeM0_o
} >G5aFk
public int getCountId(){ yvB]rz} i
return countId; K3!3[dR*
} @Go_5X(
} :TQp,CEa
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CountCache.java Pm/<^z%
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/* ftYJ 3/ WH
* CountCache.java O*:87:I d
* Wu][A\3D1
* Created on 2007年1月1日, 下午5:01 A%8
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* +_]Ui| l
* To change this template, choose Tools | Options and locate the template under (]#^q8)]\9
* the Source Creation and Management node. Right-click the template and choose A 6S0dX
* Open. You can then make changes to the template in the Source Editor. ='m$O
*/ /z-rBfdy^
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package com.tot.count; 7h
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import java.util.*; W[&nQW$E
/** 9mi@PW}1
* ]U>MYdGWb
* @author q }@L "a`
*/ hZ4 5i?%
public class CountCache { N1'`^a y$
public static LinkedList list=new LinkedList(); e gq,)6>
/** Creates a new instance of CountCache */ w0BphK[
public CountCache() {} eft=k}
public static void add(CountBean cb){ |*{*tW C1
if(cb!=null){ O\=Z;}<N
list.add(cb); F1yn@a "=J
} OR@
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} 9kD#'BxC
} agUdI_'~@9
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CountControl.java CPJ<A,V
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/* 5eTA]
* CountThread.java %L.S~dN6
* d7V/#34
* Created on 2007年1月1日, 下午4:57 s 4`-mIa
* G+c&e:ip<
* To change this template, choose Tools | Options and locate the template under }WsPu o
* the Source Creation and Management node. Right-click the template and choose /]U$OP*0
* Open. You can then make changes to the template in the Source Editor. lju5+0BSb
*/ kORWj<
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package com.tot.count; mE<_oRM)
import tot.db.DBUtils; kZ%
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import java.sql.*; iV{_?f1jo
/** P#A,(Bke3
* fV"Y/9}(
* @author d4b!
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*/ f+:iz'b#U
public class CountControl{ $wM..ee
private static long lastExecuteTime=0;//上次更新时间 (:bf m
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 vU>^
/** Creates a new instance of CountThread */ 0fqcPi
public CountControl() {} q'jOI_b
public synchronized void executeUpdate(){ e i=
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Connection conn=null; \'y]m B~k
PreparedStatement ps=null;
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try{ )w].m
conn = DBUtils.getConnection(); s@L ;3WdO
conn.setAutoCommit(false); #*A&jo'E
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); LDg9@esi
for(int i=0;i<CountCache.list.size();i++){ WDw<kX 6p
CountBean cb=(CountBean)CountCache.list.getFirst(); B!&5*f}*
CountCache.list.removeFirst(); !td!">r46e
ps.setInt(1, cb.getCountId()); n{QyqI
ps.executeUpdate();⑴ 08ZvRy(Je<
//ps.addBatch();⑵ V[.{cY?6
} H>+/k-n-
//int [] counts = ps.executeBatch();⑶ t=7Gfv
conn.commit(); UuIjtqW
}catch(Exception e){
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e.printStackTrace(); ika*w
} finally{ E]#;K-j
try{ 6[t<g=
if(ps!=null) { ~ikp'5
ps.clearParameters(); ?62zv[#
ps.close(); K\-N'M!Z
ps=null; [+WsVwyf?
} xsZN@hT
}catch(SQLException e){} Xq1#rK(
DBUtils.closeConnection(conn); g=td*S
} j}Tv/O,f
} 7#)k-S!B
public long getLast(){ H
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return lastExecuteTime; `ulQ C
} g+o$&'\
public void run(){ rai'x/Ut}+
long now = System.currentTimeMillis(); qK'mF#n0#
if ((now - lastExecuteTime) > executeSep) { s`x2Go
//System.out.print("lastExecuteTime:"+lastExecuteTime); %/2
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//System.out.print(" now:"+now+"\n"); `*U@d%a
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); e,OXn gC
lastExecuteTime=now; gNr4oOR{
executeUpdate(); Jz''UJY/O
}
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else{ fS}Eu4Xe
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ](oeMl18R
} <~|n}&
} Ls2OnL9
} @6ckB (
//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 )nHMXZ>Td
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类写好了,下面是在JSP中如下调用。 C 9%bD
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<% N)(m^M(~0
CountBean cb=new CountBean(); p7+{xXf
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); pKLcg"{[F
CountCache.add(cb); W<<G
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out.print(CountCache.list.size()+"<br>"); 6`9QGi,)
CountControl c=new CountControl(); pRfKlTU\
c.run();
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out.print(CountCache.list.size()+"<br>"); Z(:\Vj"
%>