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: DtFHh/X
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CountBean.java A1INaL
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/* O-X(8<~H=
* CountData.java Xg96I:r'p
* :Y\ ~[Y
* Created on 2007年1月1日, 下午4:44 **L&I5Hhm
* W`_JERo
* To change this template, choose Tools | Options and locate the template under 1,%`vlYv
* the Source Creation and Management node. Right-click the template and choose F5qA!jZ1]
* Open. You can then make changes to the template in the Source Editor. Q{|%kU"
*/ P,ueLG=
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package com.tot.count; ?UAuUFueA
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/** {KNaJ/:>W
* Vf&U`K
* @author D9[19,2r`
*/ 1oej<67PdJ
public class CountBean { I09 W=
private String countType; o 2Nu@^+
int countId; [M[<'+^*
/** Creates a new instance of CountData */ 8Y.qP"s
public CountBean() {} v*?8 :>:}
public void setCountType(String countTypes){ !i) !|9e
this.countType=countTypes; v?OVhV
} lG\uJxV
public void setCountId(int countIds){ 'RV96lX<
this.countId=countIds; =S`h/fru
} O hk\P;}
public String getCountType(){ LDc EjFK(
return countType; NgDhdOB
}
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public int getCountId(){ SK\@w9#&$
return countId; @W>@6E
} hK3-j;eg
} |y U!d
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CountCache.java Kf:!tRE
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/* P!W%KobZ7|
* CountCache.java q$:7j5E
* a#=d{/ab
* Created on 2007年1月1日, 下午5:01 Y7.+
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* x 4+WZYv3
* To change this template, choose Tools | Options and locate the template under |+q_kx@?l
* the Source Creation and Management node. Right-click the template and choose qU!dg
* Open. You can then make changes to the template in the Source Editor. ^A@f{g$KB+
*/ s#s">hMrI
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package com.tot.count; %NrH\v{7Q
import java.util.*; Xe%J{
/** (Lgea
* v:P]o9Oj8
* @author +d6onO{8
*/ X\h.@+f=
public class CountCache { |@X^_L.!
public static LinkedList list=new LinkedList(); -xHR6
/** Creates a new instance of CountCache */ 7HDc]&z
public CountCache() {} HLW_Y|QaFo
public static void add(CountBean cb){ + +}!Gfc?s
if(cb!=null){ $Y|OGZH8E
list.add(cb); |reA`&<q
} !FL"L
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} ]zol?
} 9r].rzf9
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CountControl.java <?KPyg2
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/* /yG34) aB
* CountThread.java =HCEUB9Fs
* -i`jS_-Cv-
* Created on 2007年1月1日, 下午4:57 +& B?f
* .t_t)'L
* To change this template, choose Tools | Options and locate the template under teJt.VA7)
* the Source Creation and Management node. Right-click the template and choose 7\6g>4J^`
* Open. You can then make changes to the template in the Source Editor. jsN[Drr a
*/ T)\}V#iA*
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package com.tot.count; '5BD%#[
import tot.db.DBUtils; 3J#LxYK
import java.sql.*; i<"lXu
/** ?}KRAtJ8
* @ b!]Jw
* @author eM<N?9 s
*/ D.a>i?W
public class CountControl{ Q/S ^-&~
private static long lastExecuteTime=0;//上次更新时间 -{\(s=%
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #%"G[B
/** Creates a new instance of CountThread */ >5-1?vi
public CountControl() {} kEDpF26!
public synchronized void executeUpdate(){ duG3-E
Connection conn=null; (bb!VVA
PreparedStatement ps=null; y!=,u
try{ 7[1Lh'u
conn = DBUtils.getConnection(); SboHo({5VA
conn.setAutoCommit(false); /}m)FaAi
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Te-p0x?G.
for(int i=0;i<CountCache.list.size();i++){ n5$#M
CountBean cb=(CountBean)CountCache.list.getFirst(); 4H#-2LV`
CountCache.list.removeFirst(); x(Bt[=,K3
ps.setInt(1, cb.getCountId()); 62sl6WWS3
ps.executeUpdate();⑴ PQ4mNjXN
//ps.addBatch();⑵ RsZj
} ;ek*2Lh
//int [] counts = ps.executeBatch();⑶ Y:!L
conn.commit(); 2`4m"D tA
}catch(Exception e){ Oh! {E5!)
e.printStackTrace(); [[$CtqLg
} finally{ ;:6\w!fc
try{ \V>5)Rn
if(ps!=null) { N{v)pu.
ps.clearParameters(); =LaEEL
ps.close(); TF8#I28AD
ps=null; ^p3GT6
} iJzBd7
}catch(SQLException e){} `WayR^ 9
DBUtils.closeConnection(conn); ab6I*DbF
} ''nOXl
} } k2Q
public long getLast(){ VfcIR(
return lastExecuteTime; LCB-ewy#E
} MNu0t\`p4
public void run(){ -uYxc=4Lh
long now = System.currentTimeMillis(); :*Wq%Y=
if ((now - lastExecuteTime) > executeSep) { sM-,95H
//System.out.print("lastExecuteTime:"+lastExecuteTime); s)E \
//System.out.print(" now:"+now+"\n"); }X)vktE+|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 296}LW
lastExecuteTime=now; sycAAmH<
executeUpdate(); &&&-P\3
} 4,)9@-|0R
else{ u9!
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); L_Ok?9$
} D>7a0p784
} "/'3I/}
} u}5CzV `
//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 {,%&}kd>
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类写好了,下面是在JSP中如下调用。 OH
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<% Af _4Z]F
CountBean cb=new CountBean(); 4mvR]:G
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); E.K^v/dNdq
CountCache.add(cb); joe)b
out.print(CountCache.list.size()+"<br>"); ,CqWm9
CountControl c=new CountControl(); "`% ,l|D
c.run(); [M\ an6h6O
out.print(CountCache.list.size()+"<br>"); 3x[Cpg,
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