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: U}A+jJ
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CountBean.java He!0&B\7h
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/* #gN{8Yk>
* CountData.java ]Vwky]d
* Zt!l3(*tt
* Created on 2007年1月1日, 下午4:44 dN*<dz+4r
* 6AQ;P
* To change this template, choose Tools | Options and locate the template under #-lk=>
* the Source Creation and Management node. Right-click the template and choose [/#n+sz.A
* Open. You can then make changes to the template in the Source Editor. %7|qnh6
*/ 3b&W=1J
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package com.tot.count; RTl7vzG
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/** <K\F/`c
* 0)2lBfHQ&
* @author wG{obsL.!
*/ VGvOwd)E
public class CountBean { G,"$Erx
private String countType; 4|+
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int countId; qw, >~
/** Creates a new instance of CountData */ _^'k_a
public CountBean() {} ;%k%AXw
public void setCountType(String countTypes){ t#pY2!/T3
this.countType=countTypes; Gc 8
} .`h+fqa
public void setCountId(int countIds){ O3BU.X1'%
this.countId=countIds; to?"{
} hXrvb[6
public String getCountType(){ pP/o2
return countType; #ASu
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} Xr)d;@yi
public int getCountId(){ pH~JPNng
return countId; gRqz8UI
} {W4t]Ff
} {(MG:
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CountCache.java cEQa 6
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/* vCmh3TQ
* CountCache.java mE7Jv)@
* x)U;
* Created on 2007年1月1日, 下午5:01 (CV=0{]
* R;.WOies4
* To change this template, choose Tools | Options and locate the template under -"nYCF
* the Source Creation and Management node. Right-click the template and choose G7=8*@q>:
* Open. You can then make changes to the template in the Source Editor. a #0{tZd
*/ h n]6he
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package com.tot.count; JR>B<{xB
import java.util.*; .z4FuG,R
/** !*ucVv;
* )I$Mh@F
* @author S8cFD):q
*/ ixH7oWH#
public class CountCache { K*}j1A
public static LinkedList list=new LinkedList(); "nefRz%j+
/** Creates a new instance of CountCache */ ge?ymaU$a
public CountCache() {} R 1 b`(
public static void add(CountBean cb){ VsMN i#?
if(cb!=null){ bbM
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list.add(cb); mT9\%5d3
} 68>zO%
} ?d0Dfqh_
} :)yM9^<D
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CountControl.java S\rfR N
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/* +=8Po'E^!d
* CountThread.java _t[%@G>P
* !Yf0y;e|:
* Created on 2007年1月1日, 下午4:57 l85"C
* 0cbF.Um8
* To change this template, choose Tools | Options and locate the template under v%- V|L
* the Source Creation and Management node. Right-click the template and choose !{XO#e
* Open. You can then make changes to the template in the Source Editor. iTvCkb48m
*/ n 3]y$wK
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package com.tot.count; U
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import tot.db.DBUtils; gA|j\T{c
import java.sql.*; u^uG_^^,/
/** 7(;VUR%%.
* q'r3a+
* @author K\ ]r
*/ K7Vr$,p
public class CountControl{ D-!%L<<
private static long lastExecuteTime=0;//上次更新时间 zK92:+^C
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 BkeP?X
/** Creates a new instance of CountThread */ F"C Yrt
public CountControl() {} B;Z^.3
public synchronized void executeUpdate(){ f5-={lUlIS
Connection conn=null; FHC7\#p/9Z
PreparedStatement ps=null; T}TP.!0E
try{ u5_fM*Ka
conn = DBUtils.getConnection(); Ei<:=6EX?8
conn.setAutoCommit(false); *S4P'JSY
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Sx"I]N
for(int i=0;i<CountCache.list.size();i++){ iT"Itz-^#
CountBean cb=(CountBean)CountCache.list.getFirst(); u\wd<<I']
CountCache.list.removeFirst(); iE`aGoA
ps.setInt(1, cb.getCountId()); l :"*]m7o_
ps.executeUpdate();⑴ 7KIQ)E'kG|
//ps.addBatch();⑵ &O,$l3 P
} ZB%~>
//int [] counts = ps.executeBatch();⑶ T1&H!
conn.commit(); ~-%A@Lt
}catch(Exception e){ QAwj]_
e.printStackTrace(); 7A6sSfPUy
} finally{ }b(e
try{ J5T#}!f
if(ps!=null) { BxU1Q&
ps.clearParameters(); K=)R!e8
ps.close(); DeSTo9A}!
ps=null; 4Ccb!?
} Fm':sd)'X
}catch(SQLException e){} dFFqs&c Q
DBUtils.closeConnection(conn); QR'g*Bro
} kDh(~nfj
} +GS=zNw#
public long getLast(){ ;gnr\C*G
return lastExecuteTime; 5aNDW'z`f
} lg+g:o
public void run(){ Sq,ty{j2%
long now = System.currentTimeMillis(); Qg!*=<b
if ((now - lastExecuteTime) > executeSep) { B vc=gW
//System.out.print("lastExecuteTime:"+lastExecuteTime); 6%#'X
//System.out.print(" now:"+now+"\n"); tV9C33
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); a)Ek~{9
lastExecuteTime=now; I>#ChV)(#
executeUpdate(); <UdD@(iZ#
} ~S!kn1&O
else{ &:*+p-!2<
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); %#a%Luq
} <GRf%zJ
} 9A(K_d-!H
} +GU16+w~E
//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 \k_3IP?o=
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类写好了,下面是在JSP中如下调用。 fZfiiE~7J
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<% F`.7_D
CountBean cb=new CountBean(); oZ[ w
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 55b |zf
CountCache.add(cb); E |
out.print(CountCache.list.size()+"<br>"); e~;)-Z
CountControl c=new CountControl(); L?+|%[
c.run(); #>B1$(@
out.print(CountCache.list.size()+"<br>"); pH%c7X/[3L
%>