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: a`t<R
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CountBean.java ;D>*Pzj
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/* $kD;*v=
* CountData.java ?ypX``3#s7
* 93]67PL#+
* Created on 2007年1月1日, 下午4:44 ]hHL[hoFC
* 9esMr0*=
* To change this template, choose Tools | Options and locate the template under W!=X_
* the Source Creation and Management node. Right-click the template and choose xZc].l6
* Open. You can then make changes to the template in the Source Editor. X8uAwHa6F
*/ y(92 Th$
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package com.tot.count; .KeZZLH
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/** z7$,m#tw
* Ng 3r`S"_<
* @author zu52]$Vj
*/ H5J1j*P<d
public class CountBean { YQ
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private String countType; -+)06BqF}
int countId; |Ym3.hz
/** Creates a new instance of CountData */ tA{B~>
public CountBean() {} 8}_M1w6v
public void setCountType(String countTypes){ ymo].
this.countType=countTypes; )Bo]+\2
} :41Ch^\E
public void setCountId(int countIds){ zxhE9 [`*e
this.countId=countIds; /Y_)dz^@
} /UP1*L
public String getCountType(){ 2}<_l 2
return countType; QoBM2QYO
} o-7,P
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public int getCountId(){ \YMe&[C:o
return countId; _GF{Duxh
} +ebmve \+
} appWq}db
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CountCache.java tsf)+`vt
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/* -qNun3
* CountCache.java !Sj0! \
* 2Q81#i'Cm
* Created on 2007年1月1日, 下午5:01 %}/ |/=
* tmVGJ+gz
* To change this template, choose Tools | Options and locate the template under v3I-i|L<)
* the Source Creation and Management node. Right-click the template and choose P g.j]
* Open. You can then make changes to the template in the Source Editor. Bh0hUE
*/ FzM<0FJRX
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package com.tot.count; mR3-+dB/
import java.util.*; 5!V%0EQqw
/** q>5K:5
* NO'37d
* @author QXLHQ_V
*/ zNRR('B?
public class CountCache { HpGI\s
public static LinkedList list=new LinkedList(); QFX/x
/** Creates a new instance of CountCache */ (Rs052m1
public CountCache() {} K}a3Bj,
public static void add(CountBean cb){ (@nEe?
if(cb!=null){ <%ba
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list.add(cb); 2R=Fc@MXs
} < ?{ic2j#
} /O{iL:`
} 'J1!P:tJ
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CountControl.java rjWn>M
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/* +JlPQ~5
* CountThread.java -F~"W@9r
* /+JHnedK
* Created on 2007年1月1日, 下午4:57 a,`f`;\7N%
* W:S?_JM
* To change this template, choose Tools | Options and locate the template under zkb[u"
* the Source Creation and Management node. Right-click the template and choose mO8E-D*3
* Open. You can then make changes to the template in the Source Editor. ?&_u$Nn
*/ sp8P[W1a
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package com.tot.count; 4Gor*{
import tot.db.DBUtils; ~9ynlVb7)r
import java.sql.*; \6L,jSoBl
/** u6MHdCJ0y
* ]9hXiY
* @author GJj} |+|
*/ k\<8h%
public class CountControl{ :/XWk
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private static long lastExecuteTime=0;//上次更新时间 N;mJHr3[F
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 5v_vv'~
/** Creates a new instance of CountThread */ 0i4XS*vPv
public CountControl() {} o~`KOe
public synchronized void executeUpdate(){ yBkcYHT
Connection conn=null; 6R'z3[K9
PreparedStatement ps=null; kkU#0p? 7
try{ kA4bv}
conn = DBUtils.getConnection(); r(OH
conn.setAutoCommit(false); .8]buM5_G
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ./@C
for(int i=0;i<CountCache.list.size();i++){ YS0^!7u
CountBean cb=(CountBean)CountCache.list.getFirst(); U>0~ /o
CountCache.list.removeFirst(); Nf!WqD* je
ps.setInt(1, cb.getCountId()); VxW>XxG0
ps.executeUpdate();⑴ )uRR!<"~
//ps.addBatch();⑵ Ge^(Ag}vE
} %pj T?G7
//int [] counts = ps.executeBatch();⑶ 8z)J rO}
conn.commit(); K)N'~jCG
}catch(Exception e){ 9(pF!}1%\
e.printStackTrace(); }P\ J?8
} finally{ kHz?vVE/l
try{ rk8Cea
if(ps!=null) { Dj9ecV`
ps.clearParameters(); EV[ BB;eb
ps.close(); E>isl"
ps=null; ]QSQr*
} ap wA
}catch(SQLException e){} +N2R'Phv
DBUtils.closeConnection(conn); g+%Pg@[
} ,Fzuo:{uy
} vn1*D-?
public long getLast(){ .kc{)d*0K
return lastExecuteTime; r,Tq";N'
} }DFZ9,gQ
public void run(){ ( q}{;
long now = System.currentTimeMillis(); ,buo&DT{L
if ((now - lastExecuteTime) > executeSep) { ]6;G#
//System.out.print("lastExecuteTime:"+lastExecuteTime); *3# RS
//System.out.print(" now:"+now+"\n"); ZKF
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ;MH_pE/m
lastExecuteTime=now; ZLlAK ?N
executeUpdate(); @pN6uDD}R
} yW@YW_2;4
else{ @S)p{T5G
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 4|h>.^
} 8SOfX^;o
} 1k!$#1d<
} =;{8)m
//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 D!rD-e
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类写好了,下面是在JSP中如下调用。 3U4h>T@s|
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