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: ^O#,%>1J
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CountBean.java gO<>L0,j
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/* +F&w~UT
* CountData.java |GL#E"[&'
* 3RscuD&
* Created on 2007年1月1日, 下午4:44 q{@>2AlK
* o?$D09j;;
* To change this template, choose Tools | Options and locate the template under p}R)qz-=5U
* the Source Creation and Management node. Right-click the template and choose PLg`\|
* Open. You can then make changes to the template in the Source Editor. `zC_?+
*/ W=mh*G3y
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package com.tot.count; `iv,aQ '
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/** +H/^RvUjF
* @]WN|K
* @author M <"&$qZ$R
*/ D?qA
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public class CountBean { )Y
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private String countType; J.?6a:#bU/
int countId; nEQw6q~je
/** Creates a new instance of CountData */ :uZcN
public CountBean() {} W: cOzJ
public void setCountType(String countTypes){ zjM+F{P8
this.countType=countTypes; .2!'6;K
} /V46:`V
public void setCountId(int countIds){ O9=vz%
this.countId=countIds; 8NPt[*
} Z?G-~3]e
public String getCountType(){ n8A*Y3~R
return countType; +_06{7@h
} KSqWq:W+
public int getCountId(){ Z)|*mJ
return countId; E$4\Yc)(AL
} h?bm1e5kE
} <2diO=
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CountCache.java A"I:cw"KY
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/* !(w\%$|
* CountCache.java 7tUl$H;I/R
* 8D)*~C'85E
* Created on 2007年1月1日, 下午5:01 -HP [IJP
* $?(fiFC
* To change this template, choose Tools | Options and locate the template under ss236&
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. B:&/*HU
*/ H;G*tje/M
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package com.tot.count; (3%NudkwT
import java.util.*; NL0X =i
/** "npj%O<bd
* PZf^r
* @author N#6&t8;kTC
*/ 2y,NT|jp
public class CountCache { qdL;Ii<Y0
public static LinkedList list=new LinkedList(); 1}QU\N(t
/** Creates a new instance of CountCache */ 1;4TA}'H
public CountCache() {} D/9&pRsO
public static void add(CountBean cb){ B+*F?k[
if(cb!=null){ 8D;>] >
list.add(cb); c+_F nA
} gUy >I(
} +[V?3Gdb
} xQm!
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CountControl.java 3E+u)f lmB
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/* |B;:Ald
* CountThread.java 1$q SbQ
* {E@Vh
* Created on 2007年1月1日, 下午4:57 06]J]
* kRTT
~
* To change this template, choose Tools | Options and locate the template under Yr,e7da
* the Source Creation and Management node. Right-click the template and choose SE;Jl[PgcL
* Open. You can then make changes to the template in the Source Editor. Z[FSy-;"
*/ kZ[E493bV
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package com.tot.count; |bO}|X
import tot.db.DBUtils; S$=])^ dur
import java.sql.*; 7-'!XD!
/** ]p `#KVW
* =eDVgOZ)
* @author ql2>C.k3L
*/ 2Af1-z^^K
public class CountControl{ 3EI$tP @4
private static long lastExecuteTime=0;//上次更新时间 wg<DV!GZ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 b_|`jHes
/** Creates a new instance of CountThread */ >(|T]u](q
public CountControl() {} WDP$w(M
public synchronized void executeUpdate(){ t1 OnA#]/_
Connection conn=null; GW]Ygf1t
PreparedStatement ps=null; K`M 8[ %S
try{ y7u"a)T
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); 2Vr F~+
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); A]WU*GL2H
for(int i=0;i<CountCache.list.size();i++){ Zyu4!
CountBean cb=(CountBean)CountCache.list.getFirst(); :;#^h]Q
CountCache.list.removeFirst(); KWLI7fTgj$
ps.setInt(1, cb.getCountId()); Pn[-{nz
ps.executeUpdate();⑴ T5=3 jPQ
//ps.addBatch();⑵ 2LiJ IO8N
} X<OwB -N
//int [] counts = ps.executeBatch();⑶ lOCMKaCD
conn.commit(); `&LPqb
}catch(Exception e){ l <Tkg9
e.printStackTrace(); =d!3_IZ
} finally{ ^GD"aerNr
try{ O8wR#(/
if(ps!=null) { _Q t
ps.clearParameters(); VWj]X7v
ps.close(); &j<B22t!
ps=null; mcP]k8?C
} -S"YEH9
}catch(SQLException e){} ,_!pUal
DBUtils.closeConnection(conn); h
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} f1rP+l-C<
} QaH32(iH
public long getLast(){ rFh!&_
return lastExecuteTime; -v/1R1$e1
} z{wJQZ9"
public void run(){ Nz'fM daX,
long now = System.currentTimeMillis(); +4Aj/$%[q
if ((now - lastExecuteTime) > executeSep) { N<zD<q
//System.out.print("lastExecuteTime:"+lastExecuteTime); *Ew`Fm H
//System.out.print(" now:"+now+"\n"); (oBvpFP33
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ': 87.8$
lastExecuteTime=now; o+*YX!]#L
executeUpdate(); p`fUpARA!
} g=0`^APql
else{ AU -,
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); A_tdtN<
} Sb+^~M
} mXtsP1
} l~b# Y&
//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 ZP
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类写好了,下面是在JSP中如下调用。 z\Hg@J
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<% tg_xk+x
CountBean cb=new CountBean(); i882r=TE3
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <~@}r\
CountCache.add(cb); 2Nrb}LH
out.print(CountCache.list.size()+"<br>"); /H/@7>
CountControl c=new CountControl(); 3k(A&]~v
c.run(); 2w_[c.
out.print(CountCache.list.size()+"<br>"); !'8.qs
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