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: YfOO]{x,X
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CountBean.java [:\8Ug8
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/* B|n<{g[-cM
* CountData.java }9ZcO\M
* mbRN W
* Created on 2007年1月1日, 下午4:44 WL5!H.q
* *FEY"W+bY
* To change this template, choose Tools | Options and locate the template under j=,]b6(
* the Source Creation and Management node. Right-click the template and choose "Crm\UI6
* Open. You can then make changes to the template in the Source Editor. [XP3
*/ :i ft{XR'
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package com.tot.count; ZICcZG_y
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/** Dx<CO1%z-
* O%(k$fvM
* @author ="*8ja-K
*/ y*5bF0
public class CountBean { mf)o1O&B
private String countType; {|J'd+
int countId; _ s[v:c
/** Creates a new instance of CountData */ Qv@Z#
public CountBean() {} s8<)lO<SV.
public void setCountType(String countTypes){ 0jN?5j
this.countType=countTypes; v/yt C/WH"
} Hc{0O7
public void setCountId(int countIds){ h .Iscr^~
this.countId=countIds; zbDM+;
} V+kU^mI
public String getCountType(){ 7!E?(3$#"
return countType; gnp\z/'>
} /hMD
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public int getCountId(){ /)` kYD6
return countId; *OQr:e<}
} ;9R;D,Gk!
} g.d%z
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CountCache.java NN9`jP2
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/* BEzF'<Z
* CountCache.java ~e<v<92Xu
* I(dMiL
* Created on 2007年1月1日, 下午5:01 ;ip"V 0`
* ![BQ;X
* To change this template, choose Tools | Options and locate the template under LA.xLU3
* the Source Creation and Management node. Right-click the template and choose u9*}@{,
* Open. You can then make changes to the template in the Source Editor. 9s-op:5
*/ '}{J;moB
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package com.tot.count; *|RQ
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import java.util.*; {<HL}m@kQ
/** t1)b26;
* d4#Q<!r
* @author <z*SO
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*/ P/'~&*m-
public class CountCache { 0omg%1vt<A
public static LinkedList list=new LinkedList(); "3*Chc
/** Creates a new instance of CountCache */ wr=h=vXU[
public CountCache() {} [*j
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public static void add(CountBean cb){ pH%cbBm
if(cb!=null){ >a;^=5E
list.add(cb); -T4{PM
} AT:T%a:G?
} p0xd
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} nz|;6?LCLY
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CountControl.java fa#]G^f
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/* gOI#$-L
* CountThread.java UlHRA[SCv
* \]U@=w
* Created on 2007年1月1日, 下午4:57 -~A7o3k35
* HM])m>KeT
* To change this template, choose Tools | Options and locate the template under _XtLO-D
* the Source Creation and Management node. Right-click the template and choose 2roPZj
* Open. You can then make changes to the template in the Source Editor. kSH3)CC P
*/ WYQJ+z5
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package com.tot.count; "3{xa;c
import tot.db.DBUtils; \`#;J?Y|`F
import java.sql.*; `)F lb|da
/** O~g_rcG
* )EYsqj
* @author =z]&E 78Y
*/ 0Ng6Xg(QHc
public class CountControl{ `e0U-W]kF
private static long lastExecuteTime=0;//上次更新时间 $jb 0/
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 n37C"qJ/i
/** Creates a new instance of CountThread */ e0HG"z4
public CountControl() {} i+yqsYKO
public synchronized void executeUpdate(){ br}.s@~
Connection conn=null; xDu11W+g
PreparedStatement ps=null; .
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try{ EH"iK2n\9
conn = DBUtils.getConnection(); =YBwO. !%
conn.setAutoCommit(false); .b]g#Du=
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); YWeEvo(,=
for(int i=0;i<CountCache.list.size();i++){ PGMu6$
CountBean cb=(CountBean)CountCache.list.getFirst(); [UquI "
CountCache.list.removeFirst(); 9U6y<X
ps.setInt(1, cb.getCountId()); 6hYv
ps.executeUpdate();⑴ Qp<?[C}'W
//ps.addBatch();⑵ %4 cUa| =?
} }1w[G;$
//int [] counts = ps.executeBatch();⑶ ~)D2U:"^xm
conn.commit(); "uCx.Q9ef
}catch(Exception e){ f3U#|(%(*
e.printStackTrace(); XZuJ<]}X,
} finally{ m^h"VH,
try{ "OFYVK\]i
if(ps!=null) { Y>EwU
ps.clearParameters(); OekcU%C
ps.close(); <"/Y`/
ps=null; knpb$eX4
} '/SMqmi
}catch(SQLException e){} #O^H?3Q3
DBUtils.closeConnection(conn); \P!v9LX(
} b,7:=-D
} 8nQlmWpJ
public long getLast(){ u.0Z)j}N
return lastExecuteTime; 2Y&z}4'j
} q#I/N$F
public void run(){ iBxCk^
long now = System.currentTimeMillis(); A) p}AEBc
if ((now - lastExecuteTime) > executeSep) { 9#/z[!
//System.out.print("lastExecuteTime:"+lastExecuteTime); I1kx3CwJ{P
//System.out.print(" now:"+now+"\n"); ZP*Hx
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zUXqTcj
lastExecuteTime=now; 9+9}^B5@A
executeUpdate(); b0x9}
} (SoV2[|
else{ kX\t0'=]
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); tHXt*tzq
} X6!u(plVQ
} !y'LKze+G
} }0?642 =-
//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 [f.[C5f%"'
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类写好了,下面是在JSP中如下调用。 i5|A\Wv"
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<% k x6%5%
CountBean cb=new CountBean(); B!!xu
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); rYeFYPS
CountCache.add(cb); gx4`pH;B\
out.print(CountCache.list.size()+"<br>"); :r:5a(sq
CountControl c=new CountControl(); C$aiOK-]+
c.run(); !s?vj
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out.print(CountCache.list.size()+"<br>"); nO$(\
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%>