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: qStZW^lFeY
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CountBean.java g2RrBK,
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/* s+m3&(X
* CountData.java
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* srbES6
* Created on 2007年1月1日, 下午4:44 sA(d_Yu_
* 7];AB;0"
* To change this template, choose Tools | Options and locate the template under Aj{c s
* the Source Creation and Management node. Right-click the template and choose W(4Mvd
* Open. You can then make changes to the template in the Source Editor. #}xw
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*/ 7y?aw`Sw:
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package com.tot.count; )tvP|
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/** T0;8koj^_
* 2`'g
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* @author A4~-{.w=
*/ @> |3d
public class CountBean { Sj'Iz #
private String countType; IgIM8"N
int countId;
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/** Creates a new instance of CountData */ }/bxe0px
public CountBean() {} 1fH2obI~X
public void setCountType(String countTypes){ c80Ffq
this.countType=countTypes; BQ:hUF3
} ]qd$rX
public void setCountId(int countIds){ JW},7Ox
this.countId=countIds; P#!^9)3
} =vs]Kmm
public String getCountType(){ FoQy@GnM5
return countType; Yi?v|H<a
} ~tc,p
public int getCountId(){ Jn&^5,J]F8
return countId; drQI@sPp
} 1 2VSzIm
} V8hmfV~=]P
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CountCache.java I}sb0 Q&
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/* ?CD[jX}!
* CountCache.java s'^sT=b
* } *jmW P
* Created on 2007年1月1日, 下午5:01 ~H c5M5m
* 50CjH"3PZ`
* To change this template, choose Tools | Options and locate the template under gX|We}H
* the Source Creation and Management node. Right-click the template and choose K`0'2
* Open. You can then make changes to the template in the Source Editor. P:>]a$Is
*/ *.6m,QqJ(
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package com.tot.count; C"QB`f:
import java.util.*; udOdXz6K?
/** 6)veuA3]
* S}P rgw/
* @author #O lPnP 2
*/ iN9G`qF3!Q
public class CountCache { r4M;]
public static LinkedList list=new LinkedList(); hkB|rhJgm
/** Creates a new instance of CountCache */ mpNS}n6
public CountCache() {} xpp>5d
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public static void add(CountBean cb){ TT oW>RP#
if(cb!=null){ KPAvN M
list.add(cb); <Gna}ALkg
} #}Hdyl I\}
}
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CountControl.java (<}BlL
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/* j[A:So
* CountThread.java g`w46X
* F1t+D)KA>
* Created on 2007年1月1日, 下午4:57 :'FCeS9
* ZfXgVTJ`
* To change this template, choose Tools | Options and locate the template under {DapXx
* the Source Creation and Management node. Right-click the template and choose [V_+/[AA)
* Open. You can then make changes to the template in the Source Editor. *c>B-Fo/D
*/ V`8\)FFG
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package com.tot.count; vY7@1_"
import tot.db.DBUtils; y'!"GrbZ
import java.sql.*; &smZ;yb|'h
/** uu.}<VM.1
* ~9PZ/(
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* @author pqTaN=R8
*/ xf{ZwS%X
public class CountControl{ z8XWp[K
private static long lastExecuteTime=0;//上次更新时间 1aZGt2;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 }kF?9w
/** Creates a new instance of CountThread */ (I#mo2
public CountControl() {} ExM VGe
public synchronized void executeUpdate(){ I1#MS4;$^
Connection conn=null; K)
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PreparedStatement ps=null; #q>\6} )
try{ Omi/sKFMi
conn = DBUtils.getConnection(); ^ FM
conn.setAutoCommit(false); :G#+5 }
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); FB:nkUR`
for(int i=0;i<CountCache.list.size();i++){ K { FZ/
CountBean cb=(CountBean)CountCache.list.getFirst(); [$F*R@,&
CountCache.list.removeFirst(); |MOz>1<a
ps.setInt(1, cb.getCountId()); Uy.ihh$I-
ps.executeUpdate();⑴ 0":k[y
//ps.addBatch();⑵ mlPvF%Ba
} VkO*+"cGv
//int [] counts = ps.executeBatch();⑶ Y;'SD{On
conn.commit(); jSSEfy>^
}catch(Exception e){ -w>ss&
e.printStackTrace(); 9 r&JsCc
} finally{ $$uMu{?0i
try{ )Ay 90Wt
if(ps!=null) { CZ'm|^S
ps.clearParameters();
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ps.close(); i"=lxqWeaV
ps=null; 4UUbX
} @SyL1yFX
}catch(SQLException e){} awI{%u_(nA
DBUtils.closeConnection(conn); }'fa f{W
} `23][V
} Br15S};Ce
public long getLast(){ G%,
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return lastExecuteTime; 5KDCmw
} P-nhG
public void run(){ [qC0YM
long now = System.currentTimeMillis(); 5@-H8*
if ((now - lastExecuteTime) > executeSep) { (KwC,0p
//System.out.print("lastExecuteTime:"+lastExecuteTime); x(xi%?G
//System.out.print(" now:"+now+"\n"); sei2\l8q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "wuO[c&%/
lastExecuteTime=now; {~uTi>U
executeUpdate(); t=xEUOQAn
} p:K%-^
else{ cs?WE9N
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); @K+gh#
} .c~z^6x
} h6OQeZ.
} "bDj00nwh
//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 c{_JPy
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类写好了,下面是在JSP中如下调用。 P.5l9Ns(O
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<% u '/)l}
CountBean cb=new CountBean(); eBs.RR
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); E5@ =LS
CountCache.add(cb); VgODv
out.print(CountCache.list.size()+"<br>"); <R;wa@a>
CountControl c=new CountControl(); R y#C#0
c.run(); <n 06(9BF
out.print(CountCache.list.size()+"<br>"); 7=9>yba)^
%>