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: BCHI@a
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CountBean.java N?Ss/by8Sg
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/* `RE1q)o}8M
* CountData.java dGc>EZSdj
* 5xG/>fn
* Created on 2007年1月1日, 下午4:44 !Jo.Un7
* *Xd_=@L&B
* To change this template, choose Tools | Options and locate the template under O0"&wvR+5
* the Source Creation and Management node. Right-click the template and choose i)e)FhEY6
* Open. You can then make changes to the template in the Source Editor. O11.wLNH
*/ v aaZ
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package com.tot.count; '?!2h'
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/** 4U:+iumy2
* >l5JwwG
* @author ^F1zkIE
*/ mH3{<^Z6
public class CountBean { >JhIRf
private String countType; d>7bwG+k
int countId; g:c
@
/** Creates a new instance of CountData */ Th*mm3D6
public CountBean() {} %n#^#:
public void setCountType(String countTypes){ RrqZ5Gonj
this.countType=countTypes; qsL6*(S(r
} ?)5M3lV3k
public void setCountId(int countIds){ iF]vIg#h
this.countId=countIds; G,i%:my7
} gM3gc;
public String getCountType(){ LvS3c9|Aj
return countType; =;xlmndT,
} ;
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public int getCountId(){ /7zy5
return countId; %25_
} ) uyh
} y/2U:H
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CountCache.java HM1y$ej
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/* k
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* CountCache.java @.iOFY
* >heih%Ar0J
* Created on 2007年1月1日, 下午5:01 z*>CP
* cWM|COXL+
* To change this template, choose Tools | Options and locate the template under !ZV#~t:)
* the Source Creation and Management node. Right-click the template and choose O"9f^y*
* Open. You can then make changes to the template in the Source Editor. Z_Ma|V?6
*/ +e"}"]n
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package com.tot.count; i]LK,'
import java.util.*; \9k{"4jX\
/** Xl*-A|:j
* ig/716r|
* @author Gb\7W
*/ |@-WC.
public class CountCache { o6KBJx
public static LinkedList list=new LinkedList(); )Bk?"q
/** Creates a new instance of CountCache */ FZmYv%J
public CountCache() {} [%nG_np
public static void add(CountBean cb){ z(orA} [
if(cb!=null){ Bv@m)$9\+3
list.add(cb); y$V{yh[:
} NI s4v(!
} I}v'n{5(
} )3B5"b,
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CountControl.java mLY *
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/* .Um%6a-
* CountThread.java -{b1&
* 6l
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* Created on 2007年1月1日, 下午4:57 @7^#_772
* 16Gv?
I
h
* To change this template, choose Tools | Options and locate the template under qryt1~Dq
* the Source Creation and Management node. Right-click the template and choose 3Ob"r`
* Open. You can then make changes to the template in the Source Editor. -;`W"&`ss
*/ ^Q :K$!
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package com.tot.count; *E)Y?9u"
import tot.db.DBUtils; F<(xz=
import java.sql.*; .DvAX(2v
/** LMG\jc?,
* M<~F>(wxA
* @author NxX1_d
*/ )#ujF~w>
public class CountControl{ Gj_b GqF8}
private static long lastExecuteTime=0;//上次更新时间 D[#\Y+N
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 MM8)yCI
/** Creates a new instance of CountThread */ };!c]/,
public CountControl() {} B=c^ma
public synchronized void executeUpdate(){ .RWBn~b#I
Connection conn=null; tl^[MLQa
PreparedStatement ps=null; ;W*$<~_
try{ E0DEFB
conn = DBUtils.getConnection(); eXaDx%mM
conn.setAutoCommit(false); Rt:PW}rFf
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); GKd>AP_
for(int i=0;i<CountCache.list.size();i++){ 6~/H#8Kdn
CountBean cb=(CountBean)CountCache.list.getFirst(); P*T)/A%4
CountCache.list.removeFirst(); )eV40l$
M
ps.setInt(1, cb.getCountId()); w9PY^U.Y3e
ps.executeUpdate();⑴ ::`j@ ]
//ps.addBatch();⑵ GQZUC\cB
} J;kbY9e
//int [] counts = ps.executeBatch();⑶ jw[`_
conn.commit(); O46/[{p+8
}catch(Exception e){ vZDQ@\HrC
e.printStackTrace(); ,`7GI*Vq
} finally{ Cp* n2
try{ 8Z!ea3kAT
if(ps!=null) { K/,lw~>
ps.clearParameters(); mDmWTq\
ps.close(); r4lG 5dV
ps=null; |5/[0V-vy
} n{yjH*\Z
}catch(SQLException e){} *sG<w%%
DBUtils.closeConnection(conn); -/qrEKQ0U?
} FTenXJ/c
} yN o8R[M
public long getLast(){ HY:@=%R
return lastExecuteTime; |#B"j1D,H
} 7A|jnm
public void run(){ 4>E2G:
long now = System.currentTimeMillis(); awK'XFk
if ((now - lastExecuteTime) > executeSep) { e](=)h|
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,{50zx2
//System.out.print(" now:"+now+"\n"); <XagkD
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); m&%b;%,J
lastExecuteTime=now; \nyFN
executeUpdate(); bcs!4
} ~z}au"k
else{ !T{g& f
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Z%R%D*f@y
} <<1oc{i
} =KZ4:d5
} Vel;t<1
//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 u@EM,o
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类写好了,下面是在JSP中如下调用。 IXN4?=)I
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<% g3XAs@
CountBean cb=new CountBean(); A!kyga6F5
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Mt Z(\&~
CountCache.add(cb); QBy*y $
out.print(CountCache.list.size()+"<br>"); D=>^m=?0
CountControl c=new CountControl(); +;Gl>$
c.run(); ~e+w@ lK
out.print(CountCache.list.size()+"<br>"); Q=8
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%>