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: feT.d +Fd
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CountBean.java 8.tp#x,A
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/* t|v_[Za}Z
* CountData.java #RWmP$+#=
* &&TAX
* Created on 2007年1月1日, 下午4:44 ;*>':-4
* >$_@p(w
* To change this template, choose Tools | Options and locate the template under S<Uv/pn
* the Source Creation and Management node. Right-click the template and choose t}2M8ue(&
* Open. You can then make changes to the template in the Source Editor. x-HR [{C
*/ uE&2M>2
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package com.tot.count; o(Q='kK
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/** BF(Kaf;<t.
* vve[.Lud'
* @author Rqun}v}
*/ m$A-'*'
public class CountBean { f4+}k GJN
private String countType; `YK%I8
int countId; %s#`Z [8,
/** Creates a new instance of CountData */ 2VgVn,c
public CountBean() {} -3Auo0
public void setCountType(String countTypes){ giu8EjzK
this.countType=countTypes; |&\cr\T\r
} i&zJwUr(<
public void setCountId(int countIds){ )Zit6I
this.countId=countIds; g?e-D.pSF
} y*5$B.u`.
public String getCountType(){ @EGUQ|WL^
return countType; I.'sK9\Zp
} ~n9-
public int getCountId(){ hG>3y\!#
return countId; 1/vcj~|)t
} uz@WW!+o
} nISfRXU;
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CountCache.java ARa9Ia{@
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/* nuLxOd *n
* CountCache.java ^*+-0b;[G
* Czt>?8x`
* Created on 2007年1月1日, 下午5:01 4P$#m<;t
* te8lF{R
* To change this template, choose Tools | Options and locate the template under ]5hGSl2
* the Source Creation and Management node. Right-click the template and choose y3)R:h4AH
* Open. You can then make changes to the template in the Source Editor. gj<Y+Dv>
*/ x2 m
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package com.tot.count; "T'?Ah6
import java.util.*; x $=-lB
/** h?2 :'Vu]
* D"+xF&
* @author f/K:~#k
*/ F!qt#Sw!\
public class CountCache { *Wmn!{\g
public static LinkedList list=new LinkedList(); hu''"/raM
/** Creates a new instance of CountCache */ 7s-ZRb[)1
public CountCache() {} K/+w6d
public static void add(CountBean cb){ =_Y#uE$
if(cb!=null){ p?+*R@O
list.add(cb); czHbdEh
} _'47yq^O
} 84$#!=v
} 8I*WVa$l
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CountControl.java Q g;?C
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/* <xWBS/K
* CountThread.java }I;5yk,o
* |6}:n,KA.
* Created on 2007年1月1日, 下午4:57 D/=
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* :6Oh ?y@
* To change this template, choose Tools | Options and locate the template under .|g67PH=
* the Source Creation and Management node. Right-click the template and choose "mm|0PUJ
* Open. You can then make changes to the template in the Source Editor. 3d0Yq
*/ a;$'A[hq
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package com.tot.count; MVpk/S%W
import tot.db.DBUtils; A&~<qgBTp
import java.sql.*; |2eF~tJqc
/** 7>Oa, \
* (}C%g{8
* @author '/"x MpN 4
*/ ^%qhE8
public class CountControl{ eVYUJ,
private static long lastExecuteTime=0;//上次更新时间 DlXthRM
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 D9|?1+Kc
/** Creates a new instance of CountThread */ 5wws8w
public CountControl() {} "T_OLegdK
public synchronized void executeUpdate(){ /:j9#kj
Connection conn=null; -UM5&R+o
PreparedStatement ps=null; -bHfo%"^TT
try{ V\V:uo(C
conn = DBUtils.getConnection(); D|1pBn.b]'
conn.setAutoCommit(false); m8|&z{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); .RNr^*AQ
for(int i=0;i<CountCache.list.size();i++){ Z=vzF0
CountBean cb=(CountBean)CountCache.list.getFirst(); aTceGyWzl
CountCache.list.removeFirst(); -
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ps.setInt(1, cb.getCountId()); S}rW=hO
ps.executeUpdate();⑴ Tmo+I4qoL
//ps.addBatch();⑵ !%x=o&
} qOKC2WD
//int [] counts = ps.executeBatch();⑶ &x(^=sTHI
conn.commit(); vh~:{akR
}catch(Exception e){ /Nh:O
e.printStackTrace(); +=y ktf
} finally{ kS$HIOt823
try{ T F !Lp:
if(ps!=null) { ;rj=hc
ps.clearParameters(); *Iu
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ps.close(); GMZj@q
ps=null; Z81{v<c;
} H:ar&o#(
}catch(SQLException e){} (\si/&
DBUtils.closeConnection(conn); TT429
} `NC{+A
} %EuXL% B
public long getLast(){ ?^F#}>C
return lastExecuteTime; a/.O,&3
} G}tq'#]E{z
public void run(){ T~k5` ~\(
long now = System.currentTimeMillis(); -L/5Nbup
if ((now - lastExecuteTime) > executeSep) { S?}@2[
//System.out.print("lastExecuteTime:"+lastExecuteTime); {.We%{4V
//System.out.print(" now:"+now+"\n"); /:a~;i
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); =W9;rQm
lastExecuteTime=now; A#mf*]'
executeUpdate(); T
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} 2'"$Y'
else{ K%<Z"2!+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); T|p$Ddt`+
} %aX<p{EY
} 2#nn}HEOC
} V*U7-{ *a
//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 Dg_/Iu>OAE
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类写好了,下面是在JSP中如下调用。 {Ex0mw)T
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<% Llf>C,)
CountBean cb=new CountBean(); #gOITXKs
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); %Gn(b1X
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); nMcd(&`N
CountControl c=new CountControl(); J=/|iW
c.run(); T7YzO,b/
out.print(CountCache.list.size()+"<br>"); u>(s.4]+
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