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: RDbA"e5x
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CountBean.java 7g$t$cZby,
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/* "v06Fj>q
* CountData.java ;%)i/MGEB
* q:'(1y~
* Created on 2007年1月1日, 下午4:44 LLMkv!%D
* n\ZFPXP
* To change this template, choose Tools | Options and locate the template under )c*~Y=f
* the Source Creation and Management node. Right-click the template and choose `i}\k
* Open. You can then make changes to the template in the Source Editor. W$&Q.Z
*/ Oj2[(7mO/
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package com.tot.count; er_aol e
Sa Nx;xgi
/** F-nt7l
* J]%P
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* @author 5]{YERa'
*/ C'Ymz`iQ
public class CountBean { `:2C9,Xu
private String countType; 9H<:\-:
int countId; P>H'od
/** Creates a new instance of CountData */ Av'H(qB\K
public CountBean() {} 4DNZ y2`
public void setCountType(String countTypes){ I|.B-$gH
this.countType=countTypes; ,Ubnz
} $?GF]BT
public void setCountId(int countIds){ zUh(b=,
this.countId=countIds; D -jew &B
} ,UP6.C14
public String getCountType(){ FvkKM+?F
return countType; lfhB2^^
} ZE :oK
public int getCountId(){ k`?n("j
return countId; 5rc<ibGh
} {BJxRH"&6*
} ELm#
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CountCache.java }>j$Wr_h
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/* }b-?Dm_H
* CountCache.java [~J4:yDd=
* N9i>81tY
* Created on 2007年1月1日, 下午5:01 d&fENnt?h
* .{Xi&[jw
* To change this template, choose Tools | Options and locate the template under k~?@~xm,R
* the Source Creation and Management node. Right-click the template and choose @a~K#Bvlm
* Open. You can then make changes to the template in the Source Editor. h_cZ&P|
*/ 0I.7I#'3O
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package com.tot.count; 1.uyu
import java.util.*; 1*a2s2G
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/** w<'mV^S
* |h3YL!
* @author {30A1>0#P
*/ 6S<pWR~
public class CountCache { $FAl9
public static LinkedList list=new LinkedList(); ]!f=b\-Av
/** Creates a new instance of CountCache */ _ K9jj
public CountCache() {} \dP2xou=
public static void add(CountBean cb){ rsP1?Hxq
if(cb!=null){ zRz3ot,|
list.add(cb); ci$o~b6V
} q
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} xD~:= ]G
} EZ$m4:{e
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CountControl.java ON$u581 y
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/* 6l50IWj,T
* CountThread.java rc$G0O
* [1E u6X6
* Created on 2007年1月1日, 下午4:57 nJ6bC^*)U
* ub-ZrC'
* To change this template, choose Tools | Options and locate the template under <AB]FBo(
* the Source Creation and Management node. Right-click the template and choose {6n B83BB
* Open. You can then make changes to the template in the Source Editor. 5VISP4a
*/ GI/g@RV
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package com.tot.count; /{Nx%PqL
import tot.db.DBUtils; J3K!@m_\
import java.sql.*; x1TB
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/** 2cww7z/B
* nzU@}/A/
* @author ATwPfo8jx@
*/ KF-n_:Bd+
public class CountControl{ E")82I
private static long lastExecuteTime=0;//上次更新时间 GU_R6Wt+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 -{ZRk[>Z
/** Creates a new instance of CountThread */ <Q%\pAP}b
public CountControl() {} (pAGS{{
public synchronized void executeUpdate(){ lwa
Connection conn=null; ]/U)<{6
PreparedStatement ps=null; :V8 \^
try{ Ix}:!L
conn = DBUtils.getConnection(); Jz3u r)|
conn.setAutoCommit(false); Og^b'Kx/
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); `,xKK+~YG-
for(int i=0;i<CountCache.list.size();i++){ gi~*1RIel;
CountBean cb=(CountBean)CountCache.list.getFirst(); 0kmZO"K#e
CountCache.list.removeFirst(); 'sJYt^
ps.setInt(1, cb.getCountId()); "/wZt c
ps.executeUpdate();⑴ hMDy;oQ
//ps.addBatch();⑵ AuWEy-q?
} p6|0JBm
//int [] counts = ps.executeBatch();⑶ mI}1si=$
conn.commit(); @<l7"y;\
}catch(Exception e){ }O8$?7j(
e.printStackTrace(); ZMoN
} finally{ q*52|?
try{ @<;0h|
if(ps!=null) { O9jqeF`L=
ps.clearParameters(); 4R.rSsAH
ps.close(); % gmf
ps=null; KYMz
} SxH b76 ;
}catch(SQLException e){} PY~cu@'k{
DBUtils.closeConnection(conn); $o5<#g"/T
} cR_85
} ]H%y7kH8
public long getLast(){ y 1z4qSeM
return lastExecuteTime; 1^$ vmULj
} r6JdF!\d
public void run(){ Q/L:0ovR
long now = System.currentTimeMillis(); :IvKxOv
if ((now - lastExecuteTime) > executeSep) { qauk,t
//System.out.print("lastExecuteTime:"+lastExecuteTime); # sm>;+J
//System.out.print(" now:"+now+"\n"); QF
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); r,a V11{
lastExecuteTime=now; r+ k5Bk'
executeUpdate(); 9*U3uyPi
} Yq}(O<ol
else{ $3w a%"
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); +O2T%
} @LqLtr@A
} L^!E4[ ^4
} a}EO7tcg,
//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 *+rO3% ;t
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类写好了,下面是在JSP中如下调用。 CWHTDao
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<% 0"3l2Eo
CountBean cb=new CountBean(); dJ#mk5=
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^1nQDd*
CountCache.add(cb); -lAX-W0
out.print(CountCache.list.size()+"<br>"); h`;w/+/Zr
CountControl c=new CountControl(); %i6i.TF
c.run(); f+d[Q1
out.print(CountCache.list.size()+"<br>"); }\?UmuolQ
%>