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: 6E*Zj1KX
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CountBean.java Og&0Z)%
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/* [)b/uR
* CountData.java [T$$od[.
* o
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* Created on 2007年1月1日, 下午4:44 0ER6cTo-t
* 7|{%CckN
* To change this template, choose Tools | Options and locate the template under ByB0>G''.
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. 8KtF<`A)
*/ I&Eg-96@
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package com.tot.count; PBPJ/puW
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/** ;6\Ski0=l
* ;GSfN
* @author :5q*46n
*/ @; j0c_^"!
public class CountBean { zm_hLk
private String countType; g,z&{pZch
int countId; gZ79u
/** Creates a new instance of CountData */ ~gzpX,{n
public CountBean() {} hj#+8=
public void setCountType(String countTypes){ H)?" 8 s
this.countType=countTypes; ]0/~6f
} +Qb2LR
public void setCountId(int countIds){ \fQgiX
this.countId=countIds; 1W6n[Xg
} &Hp\("
public String getCountType(){ 7W>}7
return countType; a3E*%G
} epY;1,;>
public int getCountId(){ b`;b}ug
return countId; iz,q8}/(
} c_DB^M!h
} K{[Fa,]'
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CountCache.java SqT"/e]b'
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/* XQ|j5]
* CountCache.java QdG?"Bdt2
* >P]I&S-.
* Created on 2007年1月1日, 下午5:01 H$($l<G9C
* ={&TeMMA
* To change this template, choose Tools | Options and locate the template under `[W)6OUCx}
* the Source Creation and Management node. Right-click the template and choose U:5*i
* Open. You can then make changes to the template in the Source Editor. :ayO+fr#
*/ H 29 _ /
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package com.tot.count; 4HYH\ey
import java.util.*; =tvm=
/** ,y{fqa4
* iM-hWhU
* @author [wpt[zG
*/ (*^E7
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public class CountCache { S)AE
public static LinkedList list=new LinkedList(); \)6?u_(u
/** Creates a new instance of CountCache */ -%QEzu&
public CountCache() {} Wf&G9Be?8
public static void add(CountBean cb){ fb S.
if(cb!=null){ Q:xI}
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list.add(cb); N[?4yV2s
} B )3SiU
} #@OKp,LJ
} |H|eH~.yg&
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CountControl.java V[2<ha[n>
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/* U:\oGa84A
* CountThread.java -<VF6k<
* e715)_HD
* Created on 2007年1月1日, 下午4:57 66y ,{t
* f~(^|~ZT
* To change this template, choose Tools | Options and locate the template under oY#XWe8Om
* the Source Creation and Management node. Right-click the template and choose IEKX'+t'
* Open. You can then make changes to the template in the Source Editor. Z#E#P<&d
*/ TlZlE^EE<
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package com.tot.count; 0a;FX0S&
import tot.db.DBUtils; Jut'xA2Dr
import java.sql.*; 0z2R`=)
/** E4fvYV_ra
* W9V=hQ2
* @author ,?skJ
*/ 9?mOLDu}Q0
public class CountControl{ S
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private static long lastExecuteTime=0;//上次更新时间 ^O\1v
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7*8nUq
/** Creates a new instance of CountThread */ j2&OYg
public CountControl() {} :r|P?;t(
public synchronized void executeUpdate(){ p`V9+CA
Connection conn=null; j?` D\LZhf
PreparedStatement ps=null; -T="Ml&
try{ N7|W.(
conn = DBUtils.getConnection(); "i5AAP?_]{
conn.setAutoCommit(false); <P)%Ms
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); orN2(:Ct7
for(int i=0;i<CountCache.list.size();i++){ ,Y/>*,J
CountBean cb=(CountBean)CountCache.list.getFirst(); c\?/^xr'!}
CountCache.list.removeFirst(); Mh@ylp+q
ps.setInt(1, cb.getCountId()); _:z;j{@4
ps.executeUpdate();⑴ %li{VDb
//ps.addBatch();⑵ PYRwcJ$b\d
} !"qEB2r
//int [] counts = ps.executeBatch();⑶ gM/_:+bT>P
conn.commit(); BqJrL/(
}catch(Exception e){ 7JK 'vT
e.printStackTrace(); !c;p4B)
} finally{ 9<#R;eIsv
try{ PyJblW
if(ps!=null) { `1}yB
ps.clearParameters(); m`w6wz
ps.close(); m>m`aLrnb
ps=null; +GEKg~/4e
} :<|fZa4!"
}catch(SQLException e){} Wh&Z *J
DBUtils.closeConnection(conn); cN(QTbyl6Q
} m3ZOq
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} 91'^--N
public long getLast(){ f#JF5>o
return lastExecuteTime; !{- 3:N7
} (#>5j7i8#
public void run(){ .6]cu{K(
long now = System.currentTimeMillis(); W;j)ux7jMY
if ((now - lastExecuteTime) > executeSep) { ry=[:\Z~
//System.out.print("lastExecuteTime:"+lastExecuteTime); }T(q "Vf~
//System.out.print(" now:"+now+"\n"); >?\ !k
c
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]?5@ObG
lastExecuteTime=now; Ki6BPi^
executeUpdate();
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} /IR5[67
else{ [&59n,R`
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); )"Yah
} zL=I-f Vq
} +c2>j8e6
} 5_T>HHR6
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 2/NWWoKw
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类写好了,下面是在JSP中如下调用。 S 2` ;7
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<% Nr7.BDA
CountBean cb=new CountBean(); l`G:@}P>G
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); oieLh"$
CountCache.add(cb); ^hTJp{
out.print(CountCache.list.size()+"<br>"); YXOD
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CountControl c=new CountControl(); tg4&j$
c.run(); %bETr"Xom
out.print(CountCache.list.size()+"<br>"); )%W2XvG
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