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: '!cCMTj
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CountBean.java `$<.pOm
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/* Nk
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* CountData.java 7Lc]HSZo,
* )?naN
* Created on 2007年1月1日, 下午4:44 o>i4CCU+
* A5RN5`}
* To change this template, choose Tools | Options and locate the template under ]G=L=D^cK
* the Source Creation and Management node. Right-click the template and choose W$;,CU.v
* Open. You can then make changes to the template in the Source Editor.
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*/ V`d,qn)i
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package com.tot.count; S_4?K)n #
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/** FZ<gpIv!NS
* n;C
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* @author K Hu+9eX
*/ f#"J]p
public class CountBean { 82qoGSD.
private String countType; EHIF>@TZ
int countId; wn, KY$/
/** Creates a new instance of CountData */ qzLPw*;
public CountBean() {} SC!RbW@3
public void setCountType(String countTypes){ #ut
this.countType=countTypes; AW'0,b`v
} Jk11fn;\>
public void setCountId(int countIds){ 3`|@H-c9
this.countId=countIds; G1tY) _-8[
} rjAn@!|:+
public String getCountType(){ r:'.nhe
return countType; t?&|8SId
} I)6+6pm
public int getCountId(){ 9dLV96
return countId; KVaiugQ
} [z\$?VJspQ
} 2'\H\|
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CountCache.java g\:[
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/* `pS9_NYZ}
* CountCache.java EhvX)s
* 9c'xHO`
* Created on 2007年1月1日, 下午5:01 f:w?pE
* CL;}IBd a
* To change this template, choose Tools | Options and locate the template under ~.nmI&3
* the Source Creation and Management node. Right-click the template and choose ~2N"#b&J
* Open. You can then make changes to the template in the Source Editor. _pG-qK
*/ qLG&WB
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package com.tot.count; fk>aqm7D!
import java.util.*; IGQFtO/x
/** )
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* +oML&g-g_
* @author gp?uHKsM
*/ @)M9IOR
public class CountCache { D|p9qe5%
public static LinkedList list=new LinkedList(); 9};8?mucr
/** Creates a new instance of CountCache */ _,0
public CountCache() {} FUb\e-Q=
public static void add(CountBean cb){ Y%^w:|f^
if(cb!=null){ 5yo%$i8I
list.add(cb); k FD;i
} )[IC?U:5I
} 'ya{9EdlT
} H;LViP2K*
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CountControl.java E_wCN&`[
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/* j0aXyLNX
* CountThread.java y9GoPC`z
* ]^7@}Ce_
* Created on 2007年1月1日, 下午4:57 ^|(LAjet
* 5d^sA;c
* To change this template, choose Tools | Options and locate the template under 5m 4P\y^a
* the Source Creation and Management node. Right-click the template and choose MrFQ5:=
* Open. You can then make changes to the template in the Source Editor. Y=I'czg
*/
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package com.tot.count; n'LrQU
import tot.db.DBUtils; Uz8ff
import java.sql.*;
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/** Rsk4L0
* $GcqBg-Hi
* @author ]p GL`ge5
*/ CwzZ8.o$i
public class CountControl{ LL |r
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private static long lastExecuteTime=0;//上次更新时间 ie95rZp
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 iHf $
/** Creates a new instance of CountThread */ &h)yro
public CountControl() {} SHgN~Um
public synchronized void executeUpdate(){ 4l'fCZhA}
Connection conn=null; ZvX*t)VjTz
PreparedStatement ps=null; *OsQ}onv
try{ _6hQ %hv8
conn = DBUtils.getConnection(); Gj?t_Zln
conn.setAutoCommit(false); exUFS5d
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); |aS.a&vwR
for(int i=0;i<CountCache.list.size();i++){ b. '-?Nn
CountBean cb=(CountBean)CountCache.list.getFirst(); P3=G1=47U
CountCache.list.removeFirst(); MJO-q $)c
ps.setInt(1, cb.getCountId()); ksUcx4;a@F
ps.executeUpdate();⑴ -d/
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//ps.addBatch();⑵ d&Zpkbh"
} yx[/|nZDC4
//int [] counts = ps.executeBatch();⑶ 7xlkZF
conn.commit(); eC4[AX6e
}catch(Exception e){ 8kIksy
e.printStackTrace(); 2@],ZLa
} finally{ ML
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try{ )2o?#8J
if(ps!=null) { O8r|8]o
ps.clearParameters(); pah'>dAL
ps.close(); b_taC^-l
ps=null; |>^JRx
} SKN`2[ahD
}catch(SQLException e){} u
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DBUtils.closeConnection(conn); [|$h*YK
} VCkq"f7cw
} &Z@o Q
public long getLast(){ RbnVL$c
return lastExecuteTime; N>`Aw^ _@&
} +Kc
public void run(){ &r/Mi%
long now = System.currentTimeMillis(); $%d*@'c
if ((now - lastExecuteTime) > executeSep) { V f&zL
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//System.out.print("lastExecuteTime:"+lastExecuteTime); FD
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//System.out.print(" now:"+now+"\n"); O0v}43J[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); PFjL1=7I
lastExecuteTime=now; 9$w.9`Py
executeUpdate(); qe#tj/aZ
} 2]*OQb#O6e
else{ M|h3Wt~7
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); !f[_+CD
} TIDO@NwF
} ]%H`_8<gc
} q54]1TQ
//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 tDcT%D {:
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类写好了,下面是在JSP中如下调用。 tcI*a>
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<% FVKTbvYn
CountBean cb=new CountBean(); dZ@63a>>@
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {JT&w6Jz
CountCache.add(cb); f8dB-FlMm
out.print(CountCache.list.size()+"<br>"); &p@O_0nF
CountControl c=new CountControl();
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c.run(); Yj49t_$b
out.print(CountCache.list.size()+"<br>"); v\ )W?i*l
%>