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: niyxZ<Z
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CountBean.java =<K6gC27
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/* *dC&*6Rx
* CountData.java 6y^GMlsI
* {lppv(U
* Created on 2007年1月1日, 下午4:44 Bob-qCBV
* >4+KEK
* To change this template, choose Tools | Options and locate the template under h$6~3^g:P
* the Source Creation and Management node. Right-click the template and choose 0x^lHBYc
* Open. You can then make changes to the template in the Source Editor. 5x,/p
*/ hL}ZPHA
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package com.tot.count; *|@386\
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/** PY+4OZ$
* Qf'g2
\
* @author "];@N!dA
*/ z'"Y+EWN
public class CountBean { [1z.JfC :S
private String countType; :"@-Bcln
int countId; 8L6b:$Y3@C
/** Creates a new instance of CountData */ kN#3HI]8
public CountBean() {} 5;HCNwX
public void setCountType(String countTypes){ {&6i$4T
this.countType=countTypes; eYu 0")
} :s-9@Yl|
public void setCountId(int countIds){ 9E[==2TO
this.countId=countIds; !?|xeQ}
} LPca+o|f
public String getCountType(){ |TR
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return countType; @:>gRD
} qmvQd8|XR
public int getCountId(){ N\rL ~4/
return countId; MGre_=Dm_
} G68@(<<Z
} ;=6EBP%
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CountCache.java *O_^C
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/* =([4pG
* CountCache.java dt"&
* _8\B~;0
* Created on 2007年1月1日, 下午5:01 +!$`0v
* roBb8M|q
* To change this template, choose Tools | Options and locate the template under ~_g{P3
* the Source Creation and Management node. Right-click the template and choose @S>;t)\J
* Open. You can then make changes to the template in the Source Editor. Ap4.c8f?Q-
*/ $~%h4
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package com.tot.count; lXzm)
import java.util.*; !aL=R)G&e
/** ~CdW:t
* ,@Kn@%?$
* @author :AI%{EV-L
*/ g=,}j]tl
public class CountCache { pUW7p
public static LinkedList list=new LinkedList(); TZ!@IBu
/** Creates a new instance of CountCache */ wkV'']= Xg
public CountCache() {} dep"$pys>
public static void add(CountBean cb){ {esb"beGLa
if(cb!=null){ |k,-]c;6
list.add(cb); t*u#4I1
} 6E9/z
} XP?)xDr8
} vJV/3-yX
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CountControl.java PrA(==FX/
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/* ["4Tn0g ;
* CountThread.java l"jYY3N|h
* O}p<"3Ub
* Created on 2007年1月1日, 下午4:57 (Nv-wU
* )?c,&
* To change this template, choose Tools | Options and locate the template under
X>P|-n#
* the Source Creation and Management node. Right-click the template and choose ^5(d^N
* Open. You can then make changes to the template in the Source Editor. 5O
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*/ ts=:r
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package com.tot.count; ='m%Iq7X
import tot.db.DBUtils; z0 #2?o
import java.sql.*; ,CuWQ'H
/** qPN9Put
* )feZ&G]
* @author n=AcN
*/ 2i1xSKRYrD
public class CountControl{ &ODo7@v`1
private static long lastExecuteTime=0;//上次更新时间 w*;"@2y;eY
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `u PLyS.
/** Creates a new instance of CountThread */ 6]kBG?m0
public CountControl() {} Kr `/sWZ
public synchronized void executeUpdate(){ ecR)8^1 '
Connection conn=null; ]^>:)q
PreparedStatement ps=null; =
try{ J_-fs#[x
conn = DBUtils.getConnection(); E-FR
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conn.setAutoCommit(false); a7453s
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); `(=Kp=b
for(int i=0;i<CountCache.list.size();i++){ 7mMMVz2
CountBean cb=(CountBean)CountCache.list.getFirst(); cO5zg<wF
CountCache.list.removeFirst(); +mzLOJed
ps.setInt(1, cb.getCountId()); $bFK2yx?=
ps.executeUpdate();⑴ zNdkwj p+
//ps.addBatch();⑵ ASre@pW
} kfT*G
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//int [] counts = ps.executeBatch();⑶ s(J>yd=
conn.commit(); FF!PmfF'
}catch(Exception e){ ela^L_N hF
e.printStackTrace(); mtn^+*
} finally{ U V*Ruy-
try{ 7]ysvSM
if(ps!=null) { 6)P.wW
ps.clearParameters(); CH
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ps.close(); NY.* S6
ps=null; ~(kqq#=s
} 6N5(DD
}catch(SQLException e){} 1 <+aF,
DBUtils.closeConnection(conn); +}a(jO
} Jww#zEK
} X;Sb^c"j1
public long getLast(){ x&0kIF'lq
return lastExecuteTime; f.+1Ubq!5
} WvSm!W
public void run(){ 9OW8/H&!
long now = System.currentTimeMillis(); +F2OPIanT~
if ((now - lastExecuteTime) > executeSep) { .g\Oj0Cbxh
//System.out.print("lastExecuteTime:"+lastExecuteTime); K,,) FM
//System.out.print(" now:"+now+"\n"); w}zmcO:x
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?+^p$'5
lastExecuteTime=now; a.}#nSYP
executeUpdate(); {\P%J:s#9
} (;%T]?<9#
else{ 4gsQ:3
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); J{Kw@_ypP
} b \ln XN
} ?4Rd4sIM$u
} V|$PO
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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 wCruj`$
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类写好了,下面是在JSP中如下调用。 :Ev
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<% z+{qQ!
CountBean cb=new CountBean(); ,f$P[c
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); k:R\;l5
CountCache.add(cb); 1BZ##xV*:G
out.print(CountCache.list.size()+"<br>"); 3Z=yCec]
CountControl c=new CountControl(); ;p`to"6IFD
c.run(); ~uty<fP
out.print(CountCache.list.size()+"<br>"); fe98Y-e
%>