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: H+\rCefba
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CountBean.java hPP+lqY[
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/* +u:8#!X$RD
* CountData.java "pQM$3n(
* I
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* Created on 2007年1月1日, 下午4:44 FK;\Nce&
* !G Z2|~f9
* To change this template, choose Tools | Options and locate the template under _hK7hvM>
* the Source Creation and Management node. Right-click the template and choose o~ 2bk<]z
* Open. You can then make changes to the template in the Source Editor. +.mIC:9
*/ !nC Z,
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package com.tot.count; ~`u?|+*BO
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/** wnN@aO6g*
* 9c4 6|
* @author dGrOw)
*/ 5d<-y2!M
public class CountBean { coiTVDwA
private String countType; O=G2bdY{,
int countId; v5RS <?o
/** Creates a new instance of CountData */ _LxV)
public CountBean() {} v93+<@Z
public void setCountType(String countTypes){ -|:7<$2#I
this.countType=countTypes; <~<I K=n
} aG?'F`UQ
public void setCountId(int countIds){ ;xXHSxa:=W
this.countId=countIds; b8feo'4Z
} 2p8JqZMQb
public String getCountType(){ G]=U=9ZI
return countType; ]nEN3RJ
} rKP"|+^
public int getCountId(){ 9v_gR52vh
return countId; x.<^L] "
} 0[x?Q[~S_0
} 8HxB\ !0F?
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CountCache.java w(<;
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/* rbqH9 S
* CountCache.java gh['T,
* !c\s)&U7B
* Created on 2007年1月1日, 下午5:01 PQlG!
* n)8bkcZCp+
* To change this template, choose Tools | Options and locate the template under vWXj6}
* the Source Creation and Management node. Right-click the template and choose sO~N2
* Open. You can then make changes to the template in the Source Editor. <~u.:x@ R
*/ JwRdr8q
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package com.tot.count; ph<Z/wlz
import java.util.*; v'2EYTVNJD
/** \V +$2
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* jCtl
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* @author r9yUye}
*/ q;}^Jpb;
public class CountCache { 8L|rj4z<#
public static LinkedList list=new LinkedList(); 7'xT)~*$4
/** Creates a new instance of CountCache */ 7"Zr:|$U
public CountCache() {} ?k<wI)JR
public static void add(CountBean cb){ GmcxN<
if(cb!=null){
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list.add(cb); .KIAeCvl\
} )><cL:IJ}S
} mO?G[?*\
} |0b$60m$!t
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CountControl.java +wY3E*hU
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/* Km'd=B>Jy
* CountThread.java VjMd&>G
* \V7Hi\)
* Created on 2007年1月1日, 下午4:57 "a?k #!E
* k(3s^B
* To change this template, choose Tools | Options and locate the template under D@"q2 !
* the Source Creation and Management node. Right-click the template and choose <(>v|5K0]
* Open. You can then make changes to the template in the Source Editor. Z5bmqhDo[
*/ @ J!)o d
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package com.tot.count; OE}L})"
import tot.db.DBUtils; s<sqO,!
import java.sql.*; a^)7&|$ E
/** '4L
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* WvAl!^{`
* @author RIC'JLWQ
*/ &dbX>u q
public class CountControl{ 66[yL(*+
private static long lastExecuteTime=0;//上次更新时间 H
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0;!aO.l]K
/** Creates a new instance of CountThread */ dWg$yH
public CountControl() {} 2j=3i@
public synchronized void executeUpdate(){ H_o<!YxK
Connection conn=null;
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PreparedStatement ps=null; V<\:iNXX{
try{ %[B &JhT
conn = DBUtils.getConnection(); u8~.6]Ae
conn.setAutoCommit(false); "@$o'rfT
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); )m\%L`+
for(int i=0;i<CountCache.list.size();i++){ 4T Gg`$e;
CountBean cb=(CountBean)CountCache.list.getFirst(); 8T&m{s
CountCache.list.removeFirst(); w44{~[0d4
ps.setInt(1, cb.getCountId()); E IsA2 f
ps.executeUpdate();⑴ #v89`$#`2
//ps.addBatch();⑵ S;Lqx5Cd
} :uu\q7@'
//int [] counts = ps.executeBatch();⑶ 1k-^LdDj
conn.commit(); nm*1JA.:
}catch(Exception e){ 7V 2%
e.printStackTrace(); 6i9m!YQV
} finally{ =uKK{\+|Y
try{ RRV@nDf
if(ps!=null) { ZZ] /9oiF%
ps.clearParameters(); E$F)z
ps.close(); [\ @!~F{
ps=null; $O%lYQY]
} B5=L</Aj
}catch(SQLException e){} O)\xElu
DBUtils.closeConnection(conn); v\n!Li H
} zOg#=ql
} M\enjB7k
public long getLast(){ ky#<\K1}'
return lastExecuteTime; 3543[W#a
}
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public void run(){ pZlBpGQf
long now = System.currentTimeMillis(); %vxd($Ti"
if ((now - lastExecuteTime) > executeSep) { 1Q#hanh_`
//System.out.print("lastExecuteTime:"+lastExecuteTime); P]yER9'
//System.out.print(" now:"+now+"\n"); _&19OD%
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); l1gAm #
lastExecuteTime=now; FT[wa-b
executeUpdate(); sOzjViv
} )n5]+VTZ5
else{ N95"dNZE
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); dK|MQ <
} [0m'a\YE9
} o:f=dBmoX
} 7M3q|7?
//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 }1:jM_H)k
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类写好了,下面是在JSP中如下调用。 o!sxfJKl
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<% jcXb@FE6
CountBean cb=new CountBean(); O4]Ss}ol
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); &|n*&@fF
CountCache.add(cb); 5NJ@mm{0
out.print(CountCache.list.size()+"<br>"); E36<Wog
CountControl c=new CountControl(); ugVsp&i#
c.run(); !xj >~7
out.print(CountCache.list.size()+"<br>"); HR['y9U
%>