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: )
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CountBean.java .Sm7na
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/* /"
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* CountData.java ZT!DTb
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* \
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* Created on 2007年1月1日, 下午4:44 d+l@hgz~
* i-$]Tg
* To change this template, choose Tools | Options and locate the template under (@]{=q<
* the Source Creation and Management node. Right-click the template and choose V5m4dQ>t
* Open. You can then make changes to the template in the Source Editor. hC,EO&
*/ 4]B(2FR[8
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package com.tot.count; JPRl/P$
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/** Z{|wjZb(
* >Qr(#Bt)
* @author 0P z"[
*/ %kUIIHV}
public class CountBean { yqZKn=1:
private String countType; ftRf~5d2
int countId; ki39$A'8
/** Creates a new instance of CountData */ Y}QtgZEt
public CountBean() {} THC34u]
public void setCountType(String countTypes){ !gu#
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this.countType=countTypes; h?jKq2`
} !IF#L0z
public void setCountId(int countIds){ ~0eJ6i
this.countId=countIds; O1Vs!
} X&b)E0]pR
public String getCountType(){ Ny\p$v
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return countType; zyTeF~_
} l!5fuB8
public int getCountId(){ DHQavHqbZ
return countId; v,^2'C$o
} iLD}>=
} qXcHf6
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CountCache.java <'f+nC=2
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/* jInI%
* CountCache.java JlR(U."
* s|FfBG
* Created on 2007年1月1日, 下午5:01 8cI<~|4_
* ap,%)on^
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose 9\y\{DHd
* Open. You can then make changes to the template in the Source Editor. :@K1pAh 4
*/ ai 0am
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package com.tot.count; gqw
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import java.util.*; |T3F:],`
/** hUR>NUK@8
* d^pzMaCI
* @author q.I
*/ &RF*pU>
public class CountCache { pQ2'0u5w5
public static LinkedList list=new LinkedList(); : ZehBu
/** Creates a new instance of CountCache */ cug=k
public CountCache() {} 4+?d0
public static void add(CountBean cb){ _e4%<!1
if(cb!=null){ `YL)[t? V
list.add(cb); -0P(lkylf
} {&3{_Ml
} +t[i68,%
} !N"Y
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CountControl.java J2Y
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/* &-R(u}m-F
* CountThread.java 0vYHx V
* J) I|Xot
* Created on 2007年1月1日, 下午4:57 m0M;f+^
* 2,T^L(]
* To change this template, choose Tools | Options and locate the template under Cr&,*lUo
* the Source Creation and Management node. Right-click the template and choose $- 4 Zi
* Open. You can then make changes to the template in the Source Editor. K."%PdC
*/ qL;u59
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package com.tot.count; zb_nU7Eg
import tot.db.DBUtils; iCXKi7
import java.sql.*; Tup2;\y
/** /k_?S?
* )y#~eYn
* @author X<p'&
*/ |K(jXZ)
public class CountControl{ k\/idd[
private static long lastExecuteTime=0;//上次更新时间 a]]>(Txc
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |i~Ab!*8n
/** Creates a new instance of CountThread */ F4X0DRC,G
public CountControl() {} ]:g;S,{
public synchronized void executeUpdate(){ 3q}fDM(@J
Connection conn=null; ca6kqh"
PreparedStatement ps=null; Z23*`yR
try{ rfH'&k
conn = DBUtils.getConnection(); 0r/pZ3/
conn.setAutoCommit(false); ps@;Z?Q
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); \""sf{S9
for(int i=0;i<CountCache.list.size();i++){ b~Q8&z2
CountBean cb=(CountBean)CountCache.list.getFirst(); LkK# =v
CountCache.list.removeFirst(); ud`!X#e~
ps.setInt(1, cb.getCountId()); 5&Vp(A[m[
ps.executeUpdate();⑴ m ,|)$R
//ps.addBatch();⑵ Xg^9k00C
} -F338J+J24
//int [] counts = ps.executeBatch();⑶ ]>_Ie?L)<
conn.commit(); 3*<?'O7I0
}catch(Exception e){ |A/)b78'u
e.printStackTrace(); iD"9,1@~n
} finally{ z]d2
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try{ &aLelJ~
if(ps!=null) { mSFh*FG
ps.clearParameters(); Xe. az
ps.close(); G[4$@{
ps=null; r0'6\MS13
} YEiQ`sYKG
}catch(SQLException e){} ;&$Nn'~a
DBUtils.closeConnection(conn); %j4AX
} 93]67PL#+
} [gE_\=FSKu
public long getLast(){ +[_mSt
return lastExecuteTime;
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} $!q(-+(
public void run(){ RASPOc/]
long now = System.currentTimeMillis(); Jb1L[sT2
if ((now - lastExecuteTime) > executeSep) { IizPu4|
//System.out.print("lastExecuteTime:"+lastExecuteTime); H5J1j*P<d
//System.out.print(" now:"+now+"\n"); L!l`2[F|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); m6 V L
lastExecuteTime=now; [!'fE#"a
executeUpdate(); QHmF,P
} Eb.k:8?Tn
else{ 5S/YVRXq
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8Ts_;uId
} [,?5}'we
} (_.0g}2
} ekV|a1)
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ^Yg}>?0
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类写好了,下面是在JSP中如下调用。 P7D__hoE
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<% s"-gnW
CountBean cb=new CountBean(); ?j^:jV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); o4F?Rx,L
CountCache.add(cb); X Z4q{^o
out.print(CountCache.list.size()+"<br>"); 2, R5mL$
CountControl c=new CountControl(); 5!V%0EQqw
c.run(); 40$- ]i
out.print(CountCache.list.size()+"<br>"); d,+a}eTP'
%>