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: _W3>Km-A=/
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CountBean.java _eE hIQ9
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/* %~`y82r6
* CountData.java 8)1k>=
* (1|_Nr
* Created on 2007年1月1日, 下午4:44 xD#r5
* ;ZSJ-r
* To change this template, choose Tools | Options and locate the template under 9MmAoLm
* the Source Creation and Management node. Right-click the template and choose *&m{)cTs
* Open. You can then make changes to the template in the Source Editor. '|9fDzW"]
*/ rerl-T<3
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package com.tot.count; )G
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/** &f:"p*=a\
* '4L0=G:A<q
* @author me7?
*/ SS/9fT"[
public class CountBean { )Hp{8c
private String countType; 6^Q Bol
int countId; ks=l
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/** Creates a new instance of CountData */ vuOixAkw
public CountBean() {} SR4cR)Iz
public void setCountType(String countTypes){ "K7{y4
this.countType=countTypes; 4]VoIUIuN
} xw)$).yc
public void setCountId(int countIds){ h{R>L s
this.countId=countIds; C_&-2Z
} ?(up!3S'x
public String getCountType(){ /]mfI&l+9
return countType; ~ PO)>;
} <Ag`pZ<s
public int getCountId(){ N<e=!LV
return countId; '\&t3?;
} Oc51|[
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} W[dK{?RB
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CountCache.java <vP{U
2itJD1;
/* =lE_
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* CountCache.java vw;GbQH(
* sO5~!W>Z
* Created on 2007年1月1日, 下午5:01 (sXR@Ce$
* VdVUYp
* To change this template, choose Tools | Options and locate the template under 0E6tH&
;>
* the Source Creation and Management node. Right-click the template and choose Jvk!a~e
* Open. You can then make changes to the template in the Source Editor. DvBL#iC
*/ dK5|tWJX
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package com.tot.count; ^UB<U#8,
import java.util.*; ':}
/** xXCSaBS~
* :r{;'[38
* @author GkhaB(btk'
*/ ^9{mjy0Q
public class CountCache { ^F>C|FJ2
public static LinkedList list=new LinkedList(); yc#0c[ZQu
/** Creates a new instance of CountCache */ lji&]^1
public CountCache() {} GE2^v_
public static void add(CountBean cb){ *gq~~(jH
if(cb!=null){ Z'vic#
list.add(cb); {hS9FdWA;
} u~WE}VC
} Ik4FVL8~
} hzT,0<nw
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CountControl.java ku@sQn
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/* !rK,_wH
* CountThread.java qmWK8}F.cE
* 6`ZHFem
* Created on 2007年1月1日, 下午4:57 XZ8#8Di8
* q;W(;B
* To change this template, choose Tools | Options and locate the template under w:|BQ,
* the Source Creation and Management node. Right-click the template and choose lWVvAoe
* Open. You can then make changes to the template in the Source Editor. X9J&OQ[W
*/ cv .R`)l
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package com.tot.count; =B0#z]qu
import tot.db.DBUtils; -HE@wda
import java.sql.*; gPo3jw o$
/** j9V*f
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* kw%vO6"q(
* @author aBBTcN%'
*/ }mZsK>
public class CountControl{ F5hOKUjv
private static long lastExecuteTime=0;//上次更新时间 :o)4Y
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 l,I[r$TCf
/** Creates a new instance of CountThread */ 8&g`Uy/b
public CountControl() {} lURL;h
public synchronized void executeUpdate(){ 6X2~30pdE
Connection conn=null; s.9)?<[
PreparedStatement ps=null; sQ4~oZZ
try{ )IFzal}o
conn = DBUtils.getConnection(); ,#NH]T`c1
conn.setAutoCommit(false); C78V/{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Y(qyuS3h~*
for(int i=0;i<CountCache.list.size();i++){ o7qZy |\4S
CountBean cb=(CountBean)CountCache.list.getFirst(); ai3wSUYJi
CountCache.list.removeFirst(); '@{'T LMCi
ps.setInt(1, cb.getCountId()); 2feiD?0
ps.executeUpdate();⑴ Vy-kogVt
//ps.addBatch();⑵ u_;&+o2
} LD.^.4{c:
//int [] counts = ps.executeBatch();⑶ [m}58?0~x
conn.commit(); da'7*
&/
}catch(Exception e){ QR.] ?t;1
e.printStackTrace(); {JJq/[j
} finally{ -Um|:[*I
try{ ^lt;K{
if(ps!=null) { <b5J"i&m
ps.clearParameters(); F!LVyY"w
ps.close(); 82EH'C
ps=null; 'Q^P#<<
} l2AAEB_C.
}catch(SQLException e){} e=8z,.Xk
DBUtils.closeConnection(conn); 8[z<gxP`?
} K}r@O"6*\
} A9?h*/$
public long getLast(){ /]_a\x5Ss
return lastExecuteTime; {J?#KHF'|
}
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public void run(){ +&U{>?.u
long now = System.currentTimeMillis(); |JR;E$
if ((now - lastExecuteTime) > executeSep) { 2tEA8F~k
//System.out.print("lastExecuteTime:"+lastExecuteTime); v0d<P2ix
//System.out.print(" now:"+now+"\n"); b<1k$0J6
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); nB8JdM2h{
lastExecuteTime=now; bG'"l qn
executeUpdate(); 5bfd8C
} |t1ij'N
else{ S7I8BS[*v
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :k-(%E](
} VSxls
} M)<4|x
} ,{pC1A@s
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 4!I;U>b b
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类写好了,下面是在JSP中如下调用。 k~YZT 8
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<% "1-|ahW
CountBean cb=new CountBean(); `:4\RcTb/
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); DKvNQ:fI>9
CountCache.add(cb); "I7 Sed7
out.print(CountCache.list.size()+"<br>"); No'^]r
CountControl c=new CountControl(); aS7%x>.A!
c.run(); *<5zMSZO
out.print(CountCache.list.size()+"<br>"); W=$cQ(x4Z
%>