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: _:JV-lM
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CountBean.java ML%JTx0+Z
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/* m`jGBSlw_
* CountData.java l I2UpfkBP
* l>)+HoD
* Created on 2007年1月1日, 下午4:44 %m$t'?
* 2
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* To change this template, choose Tools | Options and locate the template under ,/[1hhP@
* the Source Creation and Management node. Right-click the template and choose OOYdrv,
* Open. You can then make changes to the template in the Source Editor. Vc+~yh.)
*/ m3|l-[!OA"
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package com.tot.count; -#g0
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/** f?"909&
* fLV@~T|
* @author ][~rk?YY
*/ |^#Z!Hp_Y
public class CountBean { 5e2yJ R
private String countType; )7Oj
int countId; Z*'_/Grv?
/** Creates a new instance of CountData */ z0T6a15f!P
public CountBean() {} qnO/4\qq
public void setCountType(String countTypes){ 5'EoB^`8N~
this.countType=countTypes; yaAg!mW
} jjg&C9w T
public void setCountId(int countIds){ w# ;t$qz}
this.countId=countIds; l!IN #|{(
} Ub[UB%(T
public String getCountType(){ OO;I^`Yn
return countType; |2I
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} kZ!&3G9>-
public int getCountId(){ }m S+%w"j
return countId; (R!.=95@
} )F6p+i="
} C 6d#+
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CountCache.java r1sA^2g.
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/* ##U/Wa3
* CountCache.java y <P1VES
* `Vh&XH\S
* Created on 2007年1月1日, 下午5:01 ;\iu*1>Z,&
* @! jpJ}
* To change this template, choose Tools | Options and locate the template under I2?g'tz
* the Source Creation and Management node. Right-click the template and choose DhG{hQ[[
* Open. You can then make changes to the template in the Source Editor. bWzUWLa
*/ z{qn|#}
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package com.tot.count; Sbj{)
import java.util.*; FOqD
/** Qe=eer~jI
* :kucDQE({?
* @author Qq\hD@Z|
*/ U"K%ip:Wd
public class CountCache { +b{tk=Q:
public static LinkedList list=new LinkedList(); &9xcP.3
/** Creates a new instance of CountCache */ [8[`V)b
public CountCache() {} fjS#
public static void add(CountBean cb){ kFi=^#J{
if(cb!=null){ 8+~'T|
list.add(cb); ;5}"2hU>
} r4 ;nkx
} "=0JYh)%_
} !XY}\zKq
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CountControl.java S?Uvt?
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/* #F+b^WTR
* CountThread.java $"Nqto~
* fJn4'Q*U
* Created on 2007年1月1日, 下午4:57 KPa&P:R3
* wr2F]1bh@
* To change this template, choose Tools | Options and locate the template under 5I5#LQv0
* the Source Creation and Management node. Right-click the template and choose I@q4D1g
* Open. You can then make changes to the template in the Source Editor. ae]
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*/ J(`(PYo\i
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package com.tot.count; ~-NlTx
import tot.db.DBUtils; d C6t+
import java.sql.*; 6Ou[t6
/** </qli-fXB}
* E\~!E20^
* @author 5Veybchy "
*/ =UFmN"
public class CountControl{ Yd<q4VJR
private static long lastExecuteTime=0;//上次更新时间 /^Zgv-n
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 mQ:5(]v
/** Creates a new instance of CountThread */ Z'y:r2{ql
public CountControl() {} s=)1:jYk
public synchronized void executeUpdate(){ g]}E1H6-
Connection conn=null; >\ PNKpn{
PreparedStatement ps=null; y!kM#DC^
try{ |z.Ov&d4)(
conn = DBUtils.getConnection(); zA&]#mc
conn.setAutoCommit(false); WO{9S%ck
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); E XQ3(:&
for(int i=0;i<CountCache.list.size();i++){ $-_@MT~
CountBean cb=(CountBean)CountCache.list.getFirst(); WSV% Oy3V
CountCache.list.removeFirst(); ~`VD}{[,B
ps.setInt(1, cb.getCountId()); =%d0MZD
ps.executeUpdate();⑴ W
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//ps.addBatch();⑵ YXTd^M~@D
} [f-<M@id/
//int [] counts = ps.executeBatch();⑶ > ^d+;~Q;
conn.commit(); fvw&y+|y!
}catch(Exception e){ :JG2xtn
e.printStackTrace(); YDiru
} finally{ hkR Jqta)
try{ q=uJ^N
if(ps!=null) { mV'^4by
ps.clearParameters(); I$1~;!<
ps.close(); #jX%nqMxW
ps=null; {b26DKkQS
} 3AarRQWsn
}catch(SQLException e){} 1EA} [x
DBUtils.closeConnection(conn); m-}6DN
} ZbLN:g}
} _iW-i
public long getLast(){ O.wk*m!9
return lastExecuteTime; -'::$
{
} )Xd2qbi
public void run(){ F5/,H:K\
long now = System.currentTimeMillis(); kI#yW!
if ((now - lastExecuteTime) > executeSep) { y
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//System.out.print("lastExecuteTime:"+lastExecuteTime); di#:KW
//System.out.print(" now:"+now+"\n"); NFlrr*=t>
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); %z AN@
lastExecuteTime=now; .5?Md
executeUpdate(); >tVD[wVF0
} -nC!kpo
else{ -$5nqaK?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); GbbD)
} 9N{"ob
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} *61G<I
} a gxR
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//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 )l*6zn`z
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类写好了,下面是在JSP中如下调用。 EXTQ:HSES
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<%
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CountBean cb=new CountBean(); +G<9 |-
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); dnUiNs8
CountCache.add(cb); d(j|8/tpA
out.print(CountCache.list.size()+"<br>"); 9mfP9
CountControl c=new CountControl(); ixI fJ
c.run(); Xu#K<#V
out.print(CountCache.list.size()+"<br>"); L#NW<T
%>