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: b%C7 kL-
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CountBean.java .]<gm9l
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/* Y q|OX<i`K
* CountData.java Hxc>?
* `m"K_\w=/
* Created on 2007年1月1日, 下午4:44 DM\pi9<m
* ggfCfn
* To change this template, choose Tools | Options and locate the template under @cx#'
* the Source Creation and Management node. Right-click the template and choose heb{i5el
* Open. You can then make changes to the template in the Source Editor. !V4 (- 8
*/ vYo~36
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package com.tot.count; r9D
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/** ,#0#1k<Dm
* S~|\bnE
* @author #W_-S0>&
*/ dww4o~hO
public class CountBean { FS!vnl8`
private String countType; 2<AQ{
c
int countId; ew c:-2Y^
/** Creates a new instance of CountData */ oJE<}~_k
public CountBean() {} &a\G,Ma
public void setCountType(String countTypes){ :Z83*SPc
this.countType=countTypes; u2I@ fH/
} kaECjZ_&+
public void setCountId(int countIds){ o##!S6:A
this.countId=countIds;
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} Gu2=+?i?h
public String getCountType(){ ,Vz-w;oDn
return countType; "N}MhcdS
} &,,:pL[
public int getCountId(){ n-dC!t
return countId; Z`%^?My
} 6]HMhv
} 4T){z^"
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CountCache.java NKVLd_f k
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/* j~9![s!
* CountCache.java w`=XoYQl~*
* #??[;xjs!
* Created on 2007年1月1日, 下午5:01 &=In
* ,WoV)L'?
* To change this template, choose Tools | Options and locate the template under 7o7FW=^
* the Source Creation and Management node. Right-click the template and choose 3_{rXtT)'
* Open. You can then make changes to the template in the Source Editor. YCdtf7P=q
*/ Y|KT3
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package com.tot.count; *d 4A3|
import java.util.*; lgbq^d
/** srKEtd"
* a:1$i dj
* @author _ vAc/_N
*/ F"'
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public class CountCache { T w1&<S
public static LinkedList list=new LinkedList(); wRX#^;O9?>
/** Creates a new instance of CountCache */ 'Awd:Aed5
public CountCache() {} 4P7r\hs
public static void add(CountBean cb){ X&M04
if(cb!=null){ LMp^]*)t
list.add(cb); n6c+Okj
} $KoGh_h
} <?Z]h]C^o
} eZg>]<L
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CountControl.java w,<n5dMv
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/* ^=gN >xP
* CountThread.java oC3W_vH.%
* Juk'eH2^s
* Created on 2007年1月1日, 下午4:57 5n e&6
* | `?J2WGe
* To change this template, choose Tools | Options and locate the template under @ykl:K%ke
* the Source Creation and Management node. Right-click the template and choose Nr*o
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* Open. You can then make changes to the template in the Source Editor. V'K:52
*/ +Je%8jH
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#mkq}
package com.tot.count; h5v=h>c
import tot.db.DBUtils; .W\x{h
import java.sql.*; PM)nw;nS
/** gBXoEn]
* {!1RlW
* @author e=[@HVr
*/ hN\Q&F!
public class CountControl{ xo!2GPD.
private static long lastExecuteTime=0;//上次更新时间 Y7')~C`up^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `"#hhKG
/** Creates a new instance of CountThread */ F&7^M0x\ O
public CountControl() {} !2.eJ)G
public synchronized void executeUpdate(){ n3\~H9
Connection conn=null; q{xF7}i
PreparedStatement ps=null;
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try{ Y/L*0M.<
conn = DBUtils.getConnection(); wxF\enDY
conn.setAutoCommit(false); \[AJWyP
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); }E&:
for(int i=0;i<CountCache.list.size();i++){ Q-yNw0V}F
CountBean cb=(CountBean)CountCache.list.getFirst(); {m_y<
CountCache.list.removeFirst(); :8A@4vMS)?
ps.setInt(1, cb.getCountId()); {WTy/$ Qk
ps.executeUpdate();⑴ ?*~sx=mC
//ps.addBatch();⑵ zu,Yuq
} l4&
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//int [] counts = ps.executeBatch();⑶ .OlPVMFt
conn.commit(); R I:kp.V
}catch(Exception e){ }LoMS<O-[
e.printStackTrace(); 34J*<B[Njo
} finally{ 0~Xt_rN](
try{ l,UOP[j
if(ps!=null) { zNg[%{mz
ps.clearParameters(); MIqH%W.ru
ps.close(); okO\A^F
ps=null;
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} qu;$I'Ul%
}catch(SQLException e){} 9&Z+K'$=
DBUtils.closeConnection(conn); xiqeKoAD
} T sdgg?#
} Dnd
public long getLast(){ `4ti?^BNm
return lastExecuteTime; j-| !QlB
} $s"-r9@q
public void run(){ V \/Qik{h
long now = System.currentTimeMillis(); PlwM3lrj
if ((now - lastExecuteTime) > executeSep) { R%`fd *g
//System.out.print("lastExecuteTime:"+lastExecuteTime); #6C<P!]V
//System.out.print(" now:"+now+"\n"); 4rpry@1
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Fv:x>qZr@
lastExecuteTime=now; ~G.MaSm
executeUpdate(); [i_evsUj?
} v]T?xo~@'
else{ yqP=6
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); *Xh#W7,<
} lWUQkS
} 6d3YLb4M$i
} "@t bm[
//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 $Xqc'4YOZ
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类写好了,下面是在JSP中如下调用。 _\{/#J;lN
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<% 9I''$DVf
CountBean cb=new CountBean(); S#T u/2<}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Uz%ynH
CountCache.add(cb); Zu94dFP
out.print(CountCache.list.size()+"<br>"); i9T<(sdK+
CountControl c=new CountControl(); bEmzigN[
c.run(); zT93Sb
out.print(CountCache.list.size()+"<br>"); d?V/V'T[
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