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: \@3i=!
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CountBean.java +(QGlRd
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/* ma?$@]`k
* CountData.java r. =_=V/t
* lmgMR|v
* Created on 2007年1月1日, 下午4:44 T[*=7jnJQ
* X2/`EN\
* To change this template, choose Tools | Options and locate the template under s+$l.aIO!
* the Source Creation and Management node. Right-click the template and choose %HpTQ
* Open. You can then make changes to the template in the Source Editor. fOF02WP^
*/ 1Hp0,R}
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package com.tot.count; A !x"*
; P&Ka
/** W:ih#YW_F
* /|bir6Y:
* @author "n=`{~F
*/ HFB2ep7N
public class CountBean { ZOi8)Y~
private String countType; D9 OS,U/l
int countId; H_3S#.
/** Creates a new instance of CountData */ [j`It4^nC
public CountBean() {} h1:uTrtA
public void setCountType(String countTypes){ ,yNPD}@v>
this.countType=countTypes; +MIDq{B
} 3W5|Y@0
public void setCountId(int countIds){ Yy@;U]R
this.countId=countIds; a{mtG{Wc
} @q} .BcSg
public String getCountType(){ j_H{_Ug
return countType; s
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} V#'sH
public int getCountId(){ -"UK NB!
return countId; <}L`d(E@f
} k:nr!Y<
} [>=D9I@~
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CountCache.java ]3BTL7r
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/* z;xp1t@
* CountCache.java `_N8AA
* 6Y>MW 4q
* Created on 2007年1月1日, 下午5:01 &&\ h%-Jc
* tz4MT_f
* To change this template, choose Tools | Options and locate the template under }3!83~Qbx
* the Source Creation and Management node. Right-click the template and choose T2AyQ~5~
* Open. You can then make changes to the template in the Source Editor. ><mZOTn e;
*/ TxoMCN?7c
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package com.tot.count; nw+L _b
import java.util.*; $6Lgaz
/** |CexP^;!U
* 47ppyh6@
* @author 0m(/hK
*/ rW0# 6
public class CountCache { . p^='Kz?
public static LinkedList list=new LinkedList(); I3uaEv7OZc
/** Creates a new instance of CountCache */ <x,u!}5J
public CountCache() {} F42r]k
public static void add(CountBean cb){ @F]6[
if(cb!=null){ Qx1ZxJz #
list.add(cb); cpF\^[D
} WZ"NG|
} FVW<F(g`
} [=z1~dXKb
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CountControl.java hPE#l?H@A
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/* e#(0af8A
* CountThread.java bIu'^
* #UG| \}Lp
* Created on 2007年1月1日, 下午4:57 ZSuUmCm
* MUh)
* To change this template, choose Tools | Options and locate the template under R]VY
PNns
* the Source Creation and Management node. Right-click the template and choose zW,m3~XX:
* Open. You can then make changes to the template in the Source Editor. O8(;=exA
*/ iNUisl
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package com.tot.count; CkE@Ll3Z
import tot.db.DBUtils; 9$c0<~B\
import java.sql.*; P%z\^\p"5
/** T^B&GgW
* }QU9+<Z[r
* @author }L^Yoq]
*/ IsxPm9P2<
public class CountControl{ ^hv
private static long lastExecuteTime=0;//上次更新时间 odMjxWY
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 j#S>8:
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/** Creates a new instance of CountThread */ bo '
public CountControl() {} a,b;H(em
public synchronized void executeUpdate(){ i[`nu#n/
Connection conn=null; Q^$IlzG7i
PreparedStatement ps=null; y44FejH(v
try{ "IA[;+_"
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); sesr`,m.,
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); B$1nq#@
for(int i=0;i<CountCache.list.size();i++){ 1k6f|Al-
CountBean cb=(CountBean)CountCache.list.getFirst(); ~RlsgtX"
CountCache.list.removeFirst(); #\15,!*a=
ps.setInt(1, cb.getCountId()); A 9I5
ps.executeUpdate();⑴ CCZ'(Tkq
//ps.addBatch();⑵ T(Q(7
} x+? P/Ckg
//int [] counts = ps.executeBatch();⑶ G/l 28yt
conn.commit(); ZbmBwW_ 7
}catch(Exception e){ a?_!
e.printStackTrace(); [1OX:O|
} finally{ uVnbOqR<X
try{ K9{]v=#I
if(ps!=null) { {51<EvyE*
ps.clearParameters(); Dt)O60X3>
ps.close(); u"WqI[IV
ps=null; -&L(0?*qo
} 8GGC)2
}catch(SQLException e){} 2)_Zz~P^f
DBUtils.closeConnection(conn); ,hMdxZJd
} KwEyMR!
} s&>U-7fx"
public long getLast(){ ]Ut fI
return lastExecuteTime; !CJh6X!
} dm;C @.ML
public void run(){ W3AtO
long now = System.currentTimeMillis(); w.AF7.X`1
if ((now - lastExecuteTime) > executeSep) { puv/+!q
//System.out.print("lastExecuteTime:"+lastExecuteTime); w$E8R[J~P
//System.out.print(" now:"+now+"\n"); d&N[\5q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `>kHJI4
lastExecuteTime=now; AeQIsrAHE
executeUpdate(); lWiC$
} !(%^Tg=
else{ UKfC!YR2J8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2 q4dCbJ!
} (x+C=1,
} W
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} am+'j5`Ys
//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 } `X.^}oe
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类写好了,下面是在JSP中如下调用。 4hymQ3
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<% :)~idVlV
CountBean cb=new CountBean(); mN!5JZ'2
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); W*S!}ZT`
CountCache.add(cb); :J
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out.print(CountCache.list.size()+"<br>"); vt(A?$j|A
CountControl c=new CountControl(); hny(:Dj
c.run(); 1u%e7
out.print(CountCache.list.size()+"<br>"); @c>a
%>