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: \; XJ$~>
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CountBean.java 3Dr\ O_`u
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/* #?Ix6 {R
* CountData.java y>C
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* "smU5 s,P
* Created on 2007年1月1日, 下午4:44 L 0Ckw},,
* pW[TufTa
* To change this template, choose Tools | Options and locate the template under q>%B @'
* the Source Creation and Management node. Right-click the template and choose R*6TS"aL
* Open. You can then make changes to the template in the Source Editor. / :$WOQ
*/ x1~AY/)v
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package com.tot.count; m+M^we*R
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/** Yv1yRoDv
* 2z;nPup,
* @author pauO_'j_1p
*/ zeGWM,!
public class CountBean { 1Ne;U/
private String countType; kiF}+,z"
int countId; ",~ZO<P
/** Creates a new instance of CountData */ $bhI2%_`M
public CountBean() {} z^wod
public void setCountType(String countTypes){ p4uzw
this.countType=countTypes; U>n[R/~]
} V'b4wO1RV
public void setCountId(int countIds){ ^4IJL",
this.countId=countIds; I!!cA?W
} ;Qt%>Uo8
public String getCountType(){ @CM5e!
return countType; 0s8fF"$
} :H>I`)bw
public int getCountId(){ I*3>>VN
return countId; [#!Y7Ede
} /sYr?b!/<6
} 8}BM`@MG
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CountCache.java ,./n@.na
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/* Q)E3)),
* CountCache.java .8'c
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* -I4@6vE,
* Created on 2007年1月1日, 下午5:01 # ,H!<X;SS
* A#`$#CO
* To change this template, choose Tools | Options and locate the template under e6*,MnqBh
* the Source Creation and Management node. Right-click the template and choose |Fx *,91
* Open. You can then make changes to the template in the Source Editor. xm=Gt$>.o
*/ I>8_gp\1
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package com.tot.count; n"?*"Ya
import java.util.*; U
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/** BW)@.!C
* jcC"vr'u|
* @author ) M8,Tv*~
*/ %4R1rUrgt|
public class CountCache { id,' + <
public static LinkedList list=new LinkedList(); C`ZU.|R
/** Creates a new instance of CountCache */ jBEW("4R
public CountCache() {} o]I8Ghk>/z
public static void add(CountBean cb){ Z6b]EcP)#
if(cb!=null){
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list.add(cb); }x#e.}hf&
} JS03BItt
} ?}KD<R
} J>M 9t%f@
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CountControl.java l_;6xkv4
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/* "C3J[) qC
* CountThread.java P];0,;nF
* -F(luRBS(W
* Created on 2007年1月1日, 下午4:57
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* "([gN:
* To change this template, choose Tools | Options and locate the template under G'Wp)W;])\
* the Source Creation and Management node. Right-click the template and choose ]>Dbta.27
* Open. You can then make changes to the template in the Source Editor. Xn~\Vb
*/ +P9eE,WR
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package com.tot.count; xxg/vaQt=s
import tot.db.DBUtils; !Mgo~h"]#
import java.sql.*; EXbZ9 o*
/** Txl|F\nK`
* 6pb~+=3n
* @author R@uA4Al
*/ )zy;!
public class CountControl{ <l!:#u
private static long lastExecuteTime=0;//上次更新时间 "Uf1;;b
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 /V cbT >=
/** Creates a new instance of CountThread */ Af@\g-<W_
public CountControl() {} @+nCNXK
public synchronized void executeUpdate(){ ]H{*Z3S
Connection conn=null; gB%"JDn8
PreparedStatement ps=null; @ G!Ir"Q
try{ RnC+]J+?4
conn = DBUtils.getConnection(); GJ`._ju
conn.setAutoCommit(false); J8@.qC'!
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); I5QtPqB>
for(int i=0;i<CountCache.list.size();i++){ sZ7,7E|_
CountBean cb=(CountBean)CountCache.list.getFirst(); 2z$!}
CountCache.list.removeFirst(); hwvi tD!0
ps.setInt(1, cb.getCountId()); T12Zak4.=
ps.executeUpdate();⑴ B1Pi+-t
//ps.addBatch();⑵ LPs5LE[Pm
} 86cnEj=
//int [] counts = ps.executeBatch();⑶ L%3Bp/`S
conn.commit(); M/lC&F(
}catch(Exception e){ @+~>utr
e.printStackTrace(); y$di_)&g
} finally{ Wt@hST
try{ v:Gy>&
if(ps!=null) { pd`m//G
ps.clearParameters(); CAx
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ps.close(); !/a6;:_y
ps=null; O3T7O`H[
} k{S8q?Gc
}catch(SQLException e){} C[jX;//Jiu
DBUtils.closeConnection(conn); ,B_tAg4~
} o~CEja&(
} T.')XKP)1N
public long getLast(){ \b6{u6?+
return lastExecuteTime; ~z]VDEJ{q
} `'5vkO>
public void run(){ hbr3.<o1lY
long now = System.currentTimeMillis(); y<m[9FC}
if ((now - lastExecuteTime) > executeSep) { ]t&^o**
//System.out.print("lastExecuteTime:"+lastExecuteTime); \Wg_ gA
//System.out.print(" now:"+now+"\n");
@PLJ)RL
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 8sBT&A6&j
lastExecuteTime=now; Z'uiU e`&
executeUpdate(); ^~vM*.j~j
} 2 A";oE
else{ G; W2Z,
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Z]tQmV8e
} 79}jK"Gc
} MwQ4&z#wh
} bWlYQ
//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 _!vy|,w@e
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类写好了,下面是在JSP中如下调用。 |N)),/R_
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<% Q@PDhISa
CountBean cb=new CountBean(); XpkOC o 02
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |'P$zMAF
CountCache.add(cb); 1tI=Dwx
out.print(CountCache.list.size()+"<br>"); k?L2LIB<
CountControl c=new CountControl(); Ndb7>"W
c.run(); qP&:9eL
out.print(CountCache.list.size()+"<br>"); '3sySsD&O
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