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: '&4W@lvyz
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CountBean.java P wL]v. :
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/* !ckmNE0
* CountData.java dbF?#s~u
* !C>}j* 4
* Created on 2007年1月1日, 下午4:44 "{-jZdq'
* *{|{T_H:
* To change this template, choose Tools | Options and locate the template under mk#xbvvG
* the Source Creation and Management node. Right-click the template and choose &t1?=F,]
* Open. You can then make changes to the template in the Source Editor. A}K RXkB
*/ R/5aIh
/*=1hF
package com.tot.count; gB1w,96J
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/** ab4(?-'-
* L h"K"Uv
* @author YI!ecx%/4
*/ & yFS
public class CountBean {
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private String countType; }& ;49k
int countId; (izGF;N+
/** Creates a new instance of CountData */ r(9#kLXg
public CountBean() {} mZLrU<)Y
public void setCountType(String countTypes){ nRq@hk
this.countType=countTypes; /y/O&`X(
} >R"]{y
public void setCountId(int countIds){ mD@#,B7A
this.countId=countIds; F&?&8.
} =8BMCedH|
public String getCountType(){ $S{B{FK
return countType; -7^?40A
} wWV`k
public int getCountId(){ QRbiO
return countId; PYWp2V/
} X1Vx6+[
} D90m..\w
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CountCache.java p^1s9CM%
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/* o'nju.'
* CountCache.java
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* Y]
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* Created on 2007年1月1日, 下午5:01 NYopt?Xg
* B?d^JWTZ
* To change this template, choose Tools | Options and locate the template under R:49Gn:F
* the Source Creation and Management node. Right-click the template and choose HmxA2 ~C
* Open. You can then make changes to the template in the Source Editor. $RA8U:Q!1e
*/ Nm;(M=
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package com.tot.count; LRNgpjE}
import java.util.*; &|rh~;:jUX
/** *7MTq_K(An
* -58
* @author Wp!#OY1?
*/ xD[O8vQE
public class CountCache { nff
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public static LinkedList list=new LinkedList(); Kgev*xg
/** Creates a new instance of CountCache */ 0< i]ph
public CountCache() {} ^&gu{kP
public static void add(CountBean cb){ h>>KH*dQ
if(cb!=null){ " sh%8
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list.add(cb); 9X<o8^V
} Z!\xVCG"q
} 8}9B*m
} &fH;A X.
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CountControl.java <\i}zoPO
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/* vFuf{ @P
* CountThread.java Z)=S. )
* ')!+>b(P
* Created on 2007年1月1日, 下午4:57 F$[1KjS
* j*2Q{ik>J
* To change this template, choose Tools | Options and locate the template under pO^gooV\
* the Source Creation and Management node. Right-click the template and choose b|7c]l
* Open. You can then make changes to the template in the Source Editor. ~loJYq'y
*/ {Dv^j#
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package com.tot.count; L< 3U)Gp
import tot.db.DBUtils; 4x8e~/
import java.sql.*; 1;O%8sp&
/** /W4F(3oM
* &OpGcbf1
* @author Ur^~fW1o
*/ cb ICO
public class CountControl{ t^N
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private static long lastExecuteTime=0;//上次更新时间 a>w@9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *=+m;%]_
/** Creates a new instance of CountThread */ C)w11$.YQ9
public CountControl() {} Cso!VdCX
public synchronized void executeUpdate(){ s{IXth6
Connection conn=null; 6g\SJO-;N
PreparedStatement ps=null; tG1,AkyZ
try{ r?^[o
conn = DBUtils.getConnection(); N!O.=>8<
conn.setAutoCommit(false); H"~]|@g-p
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); EbTjBq
for(int i=0;i<CountCache.list.size();i++){ ,:RHhg
CountBean cb=(CountBean)CountCache.list.getFirst(); n.}A
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CountCache.list.removeFirst(); {R`,iWV
ps.setInt(1, cb.getCountId()); RPH]@
ps.executeUpdate();⑴ Ps<6 kQ(
//ps.addBatch();⑵ !Db0r/_:G
} ^;on
//int [] counts = ps.executeBatch();⑶ ?|Q[QP
conn.commit(); _oOEMQb
}catch(Exception e){ )TYrb:M'm
e.printStackTrace(); E:EXp7
} finally{ 6Xu^cbD
try{ R~9\mi5^UH
if(ps!=null) { {z":hmt
ps.clearParameters(); iF.eBL%
ps.close(); /]0-|Kg+R
ps=null; |$$gj[+^
} ?`& l Y
}catch(SQLException e){} M]\p9p(_
DBUtils.closeConnection(conn); >FrF"u:kM
} +f#oij
} ,mpvGvAI
public long getLast(){ eh`s fH
return lastExecuteTime; m6V:x/'=
} +kh#Jq.
public void run(){ <:v2N/i
long now = System.currentTimeMillis(); [A@K)A$f
if ((now - lastExecuteTime) > executeSep) { 8|:bis~wm
//System.out.print("lastExecuteTime:"+lastExecuteTime); )(&Z&2~A
//System.out.print(" now:"+now+"\n"); gY)NPi}!`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); qU ESN!
lastExecuteTime=now; a'sa{>
executeUpdate(); BU\P5uB!V
} %by8i1HR
else{ kpxWi=y
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); *k&yD3br-V
} R-lB.9e#M
} z]P=>w
} (X!?#)fyn
//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 C~C}b
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类写好了,下面是在JSP中如下调用。 cmw2EHTT<
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<% T#L/HD
CountBean cb=new CountBean(); *3,GQ%~/z
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); x3X^\Ig
CountCache.add(cb); FlWgTn>
out.print(CountCache.list.size()+"<br>"); z(-j%?
CountControl c=new CountControl(); AOh\%|}
c.run(); v0~'`*|&
out.print(CountCache.list.size()+"<br>"); wUnz D)
%>