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: snj+-'4T
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CountBean.java +j`*?pPD(.
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/* eRv3ZHH
* CountData.java s\kkD*
* RQe#X6'h
* Created on 2007年1月1日, 下午4:44 vLkZC
* a<vCAFQ
* To change this template, choose Tools | Options and locate the template under -.z~u/uL
* the Source Creation and Management node. Right-click the template and choose `D?vmSQ
* Open. You can then make changes to the template in the Source Editor. (a)d7y.oo
*/ kyY tL_SD
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package com.tot.count; -ud!j
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/** 2+ 9">a@
* >L=l{F6
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* @author Y|1kE;
*/ 2abWIw4
public class CountBean { d_]MqH>R\
private String countType; JsiJ=zo<
int countId; l&T;G9z
/** Creates a new instance of CountData */ n{UB^-}5
public CountBean() {} 8+GlM+>4
public void setCountType(String countTypes){ B-eYWt8s
this.countType=countTypes; 5ue{&z
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} 81aY*\
public void setCountId(int countIds){ X0
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this.countId=countIds; iL5+Uf)E3
} eOLS
public String getCountType(){ nk6xavQji
return countType; Kb4u)~S:
} NCl={O9<j
public int getCountId(){ .O lq_wuH
return countId; >eJk)qM
} >gVR5o
} srC'!I=s>8
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CountCache.java )8e_<^M
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/* NFc<%#H
* CountCache.java
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* [g<6i.<I
* Created on 2007年1月1日, 下午5:01 0~^opNR
* [nflQW6
* To change this template, choose Tools | Options and locate the template under oYqlN6n,=6
* the Source Creation and Management node. Right-click the template and choose b]*9![_
* Open. You can then make changes to the template in the Source Editor. oOJN?97!k
*/ E#_}y}7JY
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package com.tot.count; %iF<
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import java.util.*; qY0GeE>N
/** %]
* 8tPq5i
* @author BIX%Bu0'f
*/ )e{~x
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public class CountCache { Yo:>m*31
public static LinkedList list=new LinkedList(); uZW1
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/** Creates a new instance of CountCache */ 59ro-nA9v
public CountCache() {} 7?cZ9^z`w
public static void add(CountBean cb){ xt40hZ$
if(cb!=null){ pspV~9,
list.add(cb); w{Dk,9>w)
} i' N
} 13
} n; !t?jnf.
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CountControl.java )/f,.Z$
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/* Xt9?7J#\T
* CountThread.java gxL5%:@
* eGnc6)x@C
* Created on 2007年1月1日, 下午4:57 +mV4Ty
* ks'25tv}F
* To change this template, choose Tools | Options and locate the template under SOeL@!_
* the Source Creation and Management node. Right-click the template and choose v#D9yttO{
* Open. You can then make changes to the template in the Source Editor. SAXjB;VH6
*/ f'R^MX2
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package com.tot.count; PZH]9[H
import tot.db.DBUtils; W^al`lg+y
import java.sql.*; 1kTJMtZG~
/** e
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* tQ] R@i
* @author N6yqA)z?;
*/ (~/D*<A
public class CountControl{ $NJi]g|<3
private static long lastExecuteTime=0;//上次更新时间 blxH`O!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 _.wLQL~y
/** Creates a new instance of CountThread */ [YJP
public CountControl() {} "S)4Cjk
public synchronized void executeUpdate(){ RQ9T<t42
Connection conn=null; lty`7(\
PreparedStatement ps=null; bxEb2D
try{ N.BD]_C
conn = DBUtils.getConnection(); i>0I '~V
conn.setAutoCommit(false); 4z[Z3|_V
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); r"J1C
for(int i=0;i<CountCache.list.size();i++){ j}S
CountBean cb=(CountBean)CountCache.list.getFirst(); )Q(tryiSi
CountCache.list.removeFirst(); Uj6R?E{Jt
ps.setInt(1, cb.getCountId()); F]SexP4:A
ps.executeUpdate();⑴ E}\^GNT
//ps.addBatch();⑵ MT;<\T
} Q_LPLmM
//int [] counts = ps.executeBatch();⑶ IN`05 Q
conn.commit(); hGD7/qTN
}catch(Exception e){ ':F{st>&H
e.printStackTrace(); *1}9`$
} finally{ 4d9iAN
try{ .U9NQwd
if(ps!=null) { S1 %{/w
ps.clearParameters(); (a]'}c$X9`
ps.close(); [*8wv^
ps=null; luLm:NWUM
} #Rjm3#gc
}catch(SQLException e){} )N`ia%p_]
DBUtils.closeConnection(conn); A^%z;( 0p
} ;STO!^9~
} |~rDEv3
public long getLast(){ L{'qZ#N[
return lastExecuteTime; >0:h(,?V
} 4$d|}ajH
public void run(){ d/Fjs0pt
long now = System.currentTimeMillis(); '-gk))u>)
if ((now - lastExecuteTime) > executeSep) { :3{@LOil^
//System.out.print("lastExecuteTime:"+lastExecuteTime); Og"50 -
//System.out.print(" now:"+now+"\n"); ObMsncn
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); uoaF(F-
lastExecuteTime=now; 8uS1HE\%
executeUpdate(); )^g}'V=vIr
} K'N\"Y?>
else{ Yy>%dL
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); JL2IVENWc
} duV|'ntr
} tCtR(mG=A
} 7Dom[f
//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 C6CX{IA]
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类写好了,下面是在JSP中如下调用。 :#I8Cf
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<% SM![ yC
CountBean cb=new CountBean(); F)5QpDmqb
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); #=Q/<r.~G
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); 2P@>H_JFF
CountControl c=new CountControl(); mkrvWZjZX
c.run();
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out.print(CountCache.list.size()+"<br>"); ?GB($D=Y'&
%>