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: 4C#r=Uw`
%ws@t"aER
CountBean.java _,<@II
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/* `t>A~.f
* CountData.java 4Uk\h gT0
* N!//m?}
* Created on 2007年1月1日, 下午4:44 aI\:7
* Ihd{tmr<
* To change this template, choose Tools | Options and locate the template under X:/7#fcG8
* the Source Creation and Management node. Right-click the template and choose o
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* Open. You can then make changes to the template in the Source Editor. cCuK?3V4K
*/ JLbmh1'
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package com.tot.count; 0<XxR6w
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/** G+1i~&uV
* gF2,Jm@"6
* @author :'4",
*/ FN<Sagj
public class CountBean { +,_%9v?3
private String countType; Gn %"B6
int countId; V6bjVd9|Z
/** Creates a new instance of CountData */ Ftdx+\O_i&
public CountBean() {} P# |}]oG%
public void setCountType(String countTypes){ yf2P6b\
this.countType=countTypes; 3Ct:AJeg
} 'si{6t|
public void setCountId(int countIds){ zGwM# -
this.countId=countIds; b(Yxsy{U
} ]m :Y|,:6
public String getCountType(){ n}dLfg*
return countType; :rU,7`sE/
} qi['~((
public int getCountId(){ `|<? sjY
return countId; )~CNh5z6Y
} FEi@MJJ\e
} K8W99:v
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CountCache.java t[ZGY,8
+*IRI/KUD
/* K@vU_x0Sl
* CountCache.java `<6FCn4{X
* G8.nKoHv7x
* Created on 2007年1月1日, 下午5:01 +`ug?`_
* .;)V;!
* To change this template, choose Tools | Options and locate the template under 4N5\sdi
* the Source Creation and Management node. Right-click the template and choose k#-%u,t
* Open. You can then make changes to the template in the Source Editor. VV/aec8
*/ CY\D.Eow
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package com.tot.count; m:c0S8#:
import java.util.*; K,,'{j2#f
/** =&)R2pLs*
* "|BSGV!8
* @author PU4-}!K
*/ }/4),W@<
public class CountCache { wlEK"kKU
public static LinkedList list=new LinkedList(); ?KWo1
/** Creates a new instance of CountCache */ !gcea?I
public CountCache() {} - LB} =
public static void add(CountBean cb){ /CUBs!
if(cb!=null){ o?^Rw*u0/
list.add(cb); dl(!{tZ#
} HP\5gLVXY
} 7~SnY\B|
} ornU8H`
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CountControl.java 6Fc*&7Z+
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/* !;K zR&
* CountThread.java i0Rj;E=:]
* S%e)br}
* Created on 2007年1月1日, 下午4:57 bwa*|{R
* ff]fN:}V
* To change this template, choose Tools | Options and locate the template under G=LK
irj(
* the Source Creation and Management node. Right-click the template and choose
g@ .e%
* Open. You can then make changes to the template in the Source Editor. d5`D[,]d
*/ `lrNH]B
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package com.tot.count; wB:<ICm
import tot.db.DBUtils; ;#^ o5ht
import java.sql.*; /.~zk(-&h
/** v3G$9(NE;
* >hzSd@J&
* @author Qkw?QV-`k
*/ [,{Nu EI
public class CountControl{ zN=s]b=/
private static long lastExecuteTime=0;//上次更新时间 Rd<K.7&A}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 2%*\XPt)
/** Creates a new instance of CountThread */ 7-0j8$`
public CountControl() {} =\mJ5v"hA
public synchronized void executeUpdate(){ P#V}l'j(<a
Connection conn=null; QMy1!:Z&!
PreparedStatement ps=null; >nvnU`\
try{ /,~g"y.;,
conn = DBUtils.getConnection(); T^{=cx9x9
conn.setAutoCommit(false); aMVq%{U
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); [KCR@__
for(int i=0;i<CountCache.list.size();i++){ ^Pah\p4bj
CountBean cb=(CountBean)CountCache.list.getFirst(); bkz/V/ Y
CountCache.list.removeFirst(); c&Eva
ps.setInt(1, cb.getCountId()); ] g8z@r"b
ps.executeUpdate();⑴ uKj(=Rqq
//ps.addBatch();⑵ U$S{j&?
} Q#*R({)GH
//int [] counts = ps.executeBatch();⑶ 6G}4KGQc
conn.commit(); A~^x*#q{4
}catch(Exception e){ nwzyL`kF
e.printStackTrace(); Az-!X!O*f
} finally{ A8o)^T(vJ
try{ =LgMG^@mu
if(ps!=null) { mD|Q+~=|e
ps.clearParameters(); -%Rbd0gVH\
ps.close(); t<j_` %`8
ps=null; r8!pk~R5]
} <_]W1V:0
}catch(SQLException e){} LFZ*mRiuKE
DBUtils.closeConnection(conn); $*LBZcL
} !6z{~Z:
} 7j29wvSp5
public long getLast(){ >;R7r|^k
return lastExecuteTime; [_}8Vv&6
} `U|zNizO
public void run(){ C\OZs%]At
long now = System.currentTimeMillis(); #k[Y(_
if ((now - lastExecuteTime) > executeSep) { jQ7-M4qO/
//System.out.print("lastExecuteTime:"+lastExecuteTime); _Vf>>tuW
//System.out.print(" now:"+now+"\n"); >>"@0tO
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); l2YA/9.
lastExecuteTime=now; u:6R|%1fNn
executeUpdate(); O%6D2d
} !w@i,zqu
else{ 1 o_6WU
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); / {[p?7x>
} G
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} atmW? Z
} SoHaGQox
//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 dV16'
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类写好了,下面是在JSP中如下调用。 -yTIv*y
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<% Aa]3jev
CountBean cb=new CountBean(); 4tx6h<L#s
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); z.?slYe[
CountCache.add(cb); M4CC&?6\
out.print(CountCache.list.size()+"<br>"); >oaL -01i
CountControl c=new CountControl(); 1L!jI2~x}
c.run(); F6b;qb6n
out.print(CountCache.list.size()+"<br>"); )[r=(6?n
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