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: MDZb|1.AT
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CountBean.java NjLd-v"2
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/* %r!-*p<i|
* CountData.java 2oRmro
* F ry5v?22
* Created on 2007年1月1日, 下午4:44 SqLKF<tY]/
* : nn'>
* To change this template, choose Tools | Options and locate the template under U/;Vge8{
* the Source Creation and Management node. Right-click the template and choose N[%IrN3
* Open. You can then make changes to the template in the Source Editor. tVwN92*J
*/ v}U;@3W8U
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package com.tot.count; XooAL0w
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/** r0,}f\
* {1mD(+pJ{
* @author %vI]"a@
*/ psBBiHB[L
public class CountBean { 'DPSM?]fA
private String countType; x
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int countId; kBkhuKd)V
/** Creates a new instance of CountData */ aE}u5L$#
public CountBean() {} p}\!"&,^m
public void setCountType(String countTypes){ .#SWfAb2h
this.countType=countTypes; =:lacK(0
} tBt\&{=|D
public void setCountId(int countIds){ & |r)pl0$
this.countId=countIds; d*(1t\
} -Cl0!}P4I
public String getCountType(){ 3UEh%Ho
return countType; R[6&{&E:
} fjf\/%
public int getCountId(){ L=>N#QR7
return countId; 6N^FJCs
} b^1!_1c
} #F
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CountCache.java 'k hJZ:
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/* X#fI$9a
* CountCache.java I#0$5a},u^
* t_3XqjuA
* Created on 2007年1月1日, 下午5:01 |1EM )zh6
* 2Ig.hnHj
* To change this template, choose Tools | Options and locate the template under p ^Ruf?>
* the Source Creation and Management node. Right-click the template and choose 8AK#bna~-
* Open. You can then make changes to the template in the Source Editor. MQ01!Y[q_7
*/ /Bc
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package com.tot.count; S;=
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import java.util.*; k&^f Iz
/** <7qM;)g
* Ma$b(4dB
* @author F"_SCA?9?
*/ IP-mo!Y.
public class CountCache {
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public static LinkedList list=new LinkedList(); z}Q54,9m
/** Creates a new instance of CountCache */ J::dY~@
public CountCache() {} ^z_~e@U
public static void add(CountBean cb){ h4]yIM`8d
if(cb!=null){ lUDzfJ}3
list.add(cb); 3.Y/ZWON
} KV Mm<]Z
} 3AWg 43L7
} S%'t
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CountControl.java 0nC%tCV'
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/* HyB!8M|
* CountThread.java I~Ziq10
* ]R(=)
* Created on 2007年1月1日, 下午4:57 f>dWl$/_s
* 7 'N&jI
* To change this template, choose Tools | Options and locate the template under Rc @p!Xi
* the Source Creation and Management node. Right-click the template and choose 4Xlq
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* Open. You can then make changes to the template in the Source Editor. ">|fB&~A
*/ X ZfT;!wF&
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package com.tot.count; x5s Yo\
import tot.db.DBUtils; Y2}\~I0
import java.sql.*; R'He(x
/** Hq OzArp3
* M1^pf<!s
* @author %kUIIHV}
*/ M,zUg_ @
public class CountControl{ ftRf~5d2
private static long lastExecuteTime=0;//上次更新时间 |-bAzt
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !CUrpr/*
/** Creates a new instance of CountThread */ =5isT
public CountControl() {} J'W6NitMr
public synchronized void executeUpdate(){ EHmw(%a|+
Connection conn=null; ;
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PreparedStatement ps=null; J#"@~Q+a`@
try{ 7xqTTN6h
conn = DBUtils.getConnection(); dL!PpLR$2
conn.setAutoCommit(false); X&b)E0]pR
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); e2~&I`ct
for(int i=0;i<CountCache.list.size();i++){ <7-3j{065
CountBean cb=(CountBean)CountCache.list.getFirst(); <;G.(CK@n
CountCache.list.removeFirst(); [BWA$5D)Ny
ps.setInt(1, cb.getCountId()); cyL"?vR*<
ps.executeUpdate();⑴ 1$H*E~
//ps.addBatch();⑵ #!qa#.Yi
} !/2uO5
//int [] counts = ps.executeBatch();⑶ < j^8L^
conn.commit(); 1%g%I8W%
}catch(Exception e){ VG'M=O{)3
e.printStackTrace(); j&~`H:=E
} finally{ yz.a Z
try{ yy8h8{=g
if(ps!=null) { 06X4mu{
ps.clearParameters(); WKek^TW4HE
ps.close(); 2[zFKK
ps=null; j\@Ht~G
} m`_s_#
}catch(SQLException e){} 9}G.F r
DBUtils.closeConnection(conn); zg>4/10P1q
} ?>
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} G*` Y~SJp
public long getLast(){ cHP~J%&L
return lastExecuteTime; gqw
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} PaIE=Q4gJ
public void run(){ Q0l[1;$#
long now = System.currentTimeMillis(); hUR>NUK@8
if ((now - lastExecuteTime) > executeSep) { (@X].oM^y
//System.out.print("lastExecuteTime:"+lastExecuteTime); +9yV'd>U
//System.out.print(" now:"+now+"\n"); JlaT
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); DNwqi"
lastExecuteTime=now; rW),xfo0
executeUpdate(); A}"aH
} f i#p('8
else{ BeFCt;
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); d K.k,7R
} P~xP@?I%
} @?bO@
} pd%h5|*n;
//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 xQA6!j
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类写好了,下面是在JSP中如下调用。 ny++U;qi
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<% s[2>r#M
CountBean cb=new CountBean(); V
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >/J!:Htk+K
CountCache.add(cb); ku*H*o~
out.print(CountCache.list.size()+"<br>"); &-R(u}m-F
CountControl c=new CountControl(); LKX; ^
c.run(); 7^bde<0
out.print(CountCache.list.size()+"<br>"); *gGL5<%T:
%>