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: TnBG MI,g'
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CountBean.java ,o>pmaoLs
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/* y5Wqu9C\Io
* CountData.java UE,~_hp
* G2+)R^FSC
* Created on 2007年1月1日, 下午4:44 v8vh~^X%P
* ({_:^$E\
* To change this template, choose Tools | Options and locate the template under )Kk(P/s
* the Source Creation and Management node. Right-click the template and choose Fma`Cm.
* Open. You can then make changes to the template in the Source Editor. mf;^b.mKh
*/
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package com.tot.count; C3b0`|5
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/** E2h;hr;W
* WQLHjGehe
* @author M`C~6Mf+
*/ E#{WU}
public class CountBean { .f !]@"\
private String countType; `/wq3+ ?
int countId; t1:S!@
/** Creates a new instance of CountData */ /romTK4
public CountBean() {} rGn5QV
public void setCountType(String countTypes){ %hQMC'c
this.countType=countTypes; kk/+Vx~
} %j[LRY/
public void setCountId(int countIds){ YKw!pu=
this.countId=countIds; ZLN_,/7
} 1^60I#Vr@
public String getCountType(){ W]!@Zlal
return countType; 3dX=xuQ%/
} cdJ`Gk
public int getCountId(){ f.$aFOn
return countId; nT@6g|!
} 1IF'>*
} /_:T\`5uO
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CountCache.java _8x'GK
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/* EBIa%,
* CountCache.java ~D-JZx
* fNAo$O4cm
* Created on 2007年1月1日, 下午5:01 0[2BY]`Z.
* (ifqwl62
* To change this template, choose Tools | Options and locate the template under re ]Ste
* the Source Creation and Management node. Right-click the template and choose ~E<PtDab
* Open. You can then make changes to the template in the Source Editor. h+B'_`(
*/ l`v
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package com.tot.count; +(=0CA0GE
import java.util.*; Qc&-\kQ:$u
/** SLQ\Y%F
* SG
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* @author y~==waZw
*/ 2,8/Cb
public class CountCache { *l> [`U+
public static LinkedList list=new LinkedList(); IDGQIg
/** Creates a new instance of CountCache */ |5}rX!wS4
public CountCache() {} ~),;QQ,
public static void add(CountBean cb){ r
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if(cb!=null){ xZ.~:V03\t
list.add(cb); ih+*T1#:(
} %k3NT~
} (C-,ljY
} H )BOSZD
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CountControl.java QMXD9H0{
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/* Sk6b`W7$
* CountThread.java ;mf4U85
* =_$XP
* Created on 2007年1月1日, 下午4:57 dN$ 1$B^k
* a"0B?3*r46
* To change this template, choose Tools | Options and locate the template under 4
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* the Source Creation and Management node. Right-click the template and choose RLYU\@kK?
* Open. You can then make changes to the template in the Source Editor. ZdE>C
*/ a)3O? Y
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package com.tot.count; _o@(wGeu#
import tot.db.DBUtils; G$?|S@I,
import java.sql.*; 1s{ISWm
/** Hv8SYQ|
* iGG6Myp-
* @author ${A5-
*/ *'UhlFed
public class CountControl{ g".d"d{
private static long lastExecuteTime=0;//上次更新时间 :V&N\>Wo
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 [D*J[?yt
/** Creates a new instance of CountThread */ +3M$3w{2
public CountControl() {} eV[`P&j_C
public synchronized void executeUpdate(){ P'a0CE%
Connection conn=null; Wmz q
PreparedStatement ps=null; !1ML%}vvB,
try{ t{/hkXq]
conn = DBUtils.getConnection(); ,sO:$
conn.setAutoCommit(false); (H&@u9K?a?
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Jt##rVN
for(int i=0;i<CountCache.list.size();i++){ eq^TA1>T
CountBean cb=(CountBean)CountCache.list.getFirst(); cvZni#o2)
CountCache.list.removeFirst(); 'M~BE\
ps.setInt(1, cb.getCountId()); 7%{R#$F
ps.executeUpdate();⑴ 6BDt.bG
//ps.addBatch();⑵ iLF^%!:X%
} /h/6&R0l
//int [] counts = ps.executeBatch();⑶ 1a<]$tZk
conn.commit(); CD^CUbGk
}catch(Exception e){ ` *>V6B3
e.printStackTrace(); M6J/mOVx5
} finally{ xKY$L*
try{ cvKV95bn
if(ps!=null) { 1s Br.+p
ps.clearParameters(); D+f'*|
ps.close(); "kX`FaAhY
ps=null; G7
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} 3rxo,pX94
}catch(SQLException e){} u FMIY(vB
DBUtils.closeConnection(conn); DC&A1I&
} /@Ez" ?V2
} >Z *iE"9"
public long getLast(){ b& V`<'{
return lastExecuteTime; yc*<:(p
} |</"N-#S
public void run(){ >[a FOA
long now = System.currentTimeMillis(); $Z/klSEf
if ((now - lastExecuteTime) > executeSep) { ,!`SY)
//System.out.print("lastExecuteTime:"+lastExecuteTime); [_h%F,_ A
//System.out.print(" now:"+now+"\n"); \3r3{X
_<`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); IeVLn^?+:
lastExecuteTime=now; JL.5QzA
executeUpdate(); NjbwGcH%\
} t)ld<9)eB
else{ !(Q l)C
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); nB=0T`vQ
} NUMi])HkN
} 3@G;'|z
} WE")xhV6
//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 5^>n5u/
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类写好了,下面是在JSP中如下调用。 Xem 05%,
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<%
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CountBean cb=new CountBean(); U h.Sc:trA
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9mQ#L<Ps
CountCache.add(cb); vXb:
out.print(CountCache.list.size()+"<br>"); $_)=8"Sn
CountControl c=new CountControl(); ,<sm,!^<r
c.run(); {DT4mG5
out.print(CountCache.list.size()+"<br>"); eZNitGaU
%>