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: v5`Q7ZZ
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CountBean.java G~fM!F0
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/* M qG`P
* CountData.java c037#&Q%#
* _pe_w{V-b6
* Created on 2007年1月1日, 下午4:44 +*vg)F:
* E|> oseR
* To change this template, choose Tools | Options and locate the template under xv:VW<
* the Source Creation and Management node. Right-click the template and choose +=&A1{kR3
* Open. You can then make changes to the template in the Source Editor. lx"#S'^~
*/ )[d>?%vfd
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package com.tot.count; 41Htsj
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/** L6E8A?>5rD
* dzn[4
* @author C=uYX"
*/ FEzjP$
public class CountBean { ubZcpqm?Q
private String countType; /2#1Oi)o
int countId; Ihn+_Hu
/** Creates a new instance of CountData */ hA!kkNqV
public CountBean() {} NsY D~n
public void setCountType(String countTypes){ 8fX<,*#I
this.countType=countTypes; ?OFl9%\ V
} =vc8u&L2
public void setCountId(int countIds){ `R+I(Cb
this.countId=countIds; \C eP.,<
} >Qg 9KGk'
public String getCountType(){ W]U},g8Z
return countType; @Wb_Sz4`
} 2qkZ B0[
public int getCountId(){ o2vBY]Tj
return countId; Fy8$'oc
} #FQkwX'g
} !.}ZlA
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CountCache.java i9Tq h
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/* Y&JK*d
* CountCache.java n13#}i{tm
* rjLPX
* Created on 2007年1月1日, 下午5:01 wSwDhOX=
* YN >k5\M_v
* To change this template, choose Tools | Options and locate the template under MrGq{,6C
* the Source Creation and Management node. Right-click the template and choose >*FH JCe
* Open. You can then make changes to the template in the Source Editor. XwNJHOaF
*/ 5B76D12
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package com.tot.count; DtrR< &m
import java.util.*; 4>I >y@^
/** _I1:|y
* A;\1`_i0
* @author quGvq"Y>
*/ 4'
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public class CountCache { -xk.wWpV
public static LinkedList list=new LinkedList(); |1[3RnGS
/** Creates a new instance of CountCache */ UBZ37P
public CountCache() {} g{d(4=FM
public static void add(CountBean cb){ |*5803h
if(cb!=null){ G&LOjd2
list.add(cb); Spqbr@j
} ^}PG*h|
} ~Y.I;EPKt
} ccPTJ/%$
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CountControl.java `\vqDWh8-
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/* >ukn<
* CountThread.java uz%<K(:Ov
* &ap&dM0@%a
* Created on 2007年1月1日, 下午4:57 H/?@UJ5m
* RL|d-A+;
* To change this template, choose Tools | Options and locate the template under do$+ Eh
* the Source Creation and Management node. Right-click the template and choose v+b#8
* Open. You can then make changes to the template in the Source Editor. XHER [8l
*/
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package com.tot.count; v%2 @M
import tot.db.DBUtils; rUL_=>3
import java.sql.*; AIU=56+I\
/** :kb2v1{\
* 4[VW~x07
* @author *?v_AZ
*/ %/:0x:ns
public class CountControl{
}\$CU
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private static long lastExecuteTime=0;//上次更新时间 7XU$O$C
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 b$W~w*O
/** Creates a new instance of CountThread */ %&[=%zc
public CountControl() {} #PJHwvr
public synchronized void executeUpdate(){ "z6xS;
Connection conn=null; |3{"ANmm'
PreparedStatement ps=null; WNmG'hlA
try{ N R0"yJV>
conn = DBUtils.getConnection(); nd4Z5=X
conn.setAutoCommit(false); fb*h.6^y9
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); *+|,rcI
for(int i=0;i<CountCache.list.size();i++){ :H(wW
CountBean cb=(CountBean)CountCache.list.getFirst(); Q dPqcw4+X
CountCache.list.removeFirst(); H,q-*Kk
ps.setInt(1, cb.getCountId()); ;rqW?':(i
ps.executeUpdate();⑴ 9m+ejTK{U
//ps.addBatch();⑵ km,I75o.
} !-cK@>.pE
//int [] counts = ps.executeBatch();⑶ GVK c4HGt
conn.commit(); n)t'?7
}catch(Exception e){ uK;&L?WB
e.printStackTrace(); -2/&i
} finally{ ]H$Trf:L
try{ Svl;Ul
if(ps!=null) { $2J[lt?%
ps.clearParameters(); h%UM<TZ]"
ps.close(); qe<xH#6
ps=null; >.o<}!FW
} W Yo>Md
8
}catch(SQLException e){} RE%25t|
DBUtils.closeConnection(conn); 7RZ HU+
} 5!Ho[
} !+V."*]l
public long getLast(){ a9N$I@bi]
return lastExecuteTime; zc.r&(d
} 8quH#IhB
public void run(){ ZTg[}+0e
long now = System.currentTimeMillis(); bHK[Z5
if ((now - lastExecuteTime) > executeSep) { 9~5LKg7Ac
//System.out.print("lastExecuteTime:"+lastExecuteTime); -SlAt$IJ
//System.out.print(" now:"+now+"\n"); o#\c:D*k
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); %u!)1oOIz
lastExecuteTime=now; LFX[v
executeUpdate(); f!K{f[aDa
} 9cXL4
else{ UpSa7F:Uw
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'Y22HVUX
} [R(d Cq>
} dh-?_|"
} lKBI3oYn
//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 q5G`N>"V
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类写好了,下面是在JSP中如下调用。 W1
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<% S|
CountBean cb=new CountBean(); E|"QYsi.Ck
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9 Eqv^0u
CountCache.add(cb); AK//]
out.print(CountCache.list.size()+"<br>"); a^eR~efdu@
CountControl c=new CountControl(); "BA&
c.run(); 9WT{~PGj
out.print(CountCache.list.size()+"<br>"); E4N"|u|
%>