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: 6[==BbZ
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CountBean.java ^g!B.ll`
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/* O{n<WQd{CY
* CountData.java A8dI:E+$
* 8wF#e\Va0
* Created on 2007年1月1日, 下午4:44 &=-PRza%j
* o'qm82*
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* To change this template, choose Tools | Options and locate the template under vR]mSX3)?
* the Source Creation and Management node. Right-click the template and choose u@D.i4U
* Open. You can then make changes to the template in the Source Editor. k!E"wJkpz
*/ F";FG 0
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package com.tot.count;
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/** K}2Npo
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* dt~iw
* @author ]P*!'iYN(
*/ 97x%w]kV
public class CountBean { @}eNV~ROu
private String countType; R$xY8+}V
int countId; c$#GM57V
/** Creates a new instance of CountData */ .3g&9WvN!Z
public CountBean() {} 2X_ >vIlEm
public void setCountType(String countTypes){ FaWl,} ]
this.countType=countTypes; 37KU~9-A
} T}2:.Hk:N
public void setCountId(int countIds){ ; J2-rh
this.countId=countIds; lO&cCV;
} BE%Z\E[[m
public String getCountType(){ '49L(>.
return countType; /c^e&D
} T~:_}J
public int getCountId(){ GYqJ!,
return countId; cQ,9Rnfl,
} ;o >WXw
} @ta?&Qf)
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CountCache.java %O /d4
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/* 3M$X:$b
* CountCache.java X2P``YFV{
* {_as!5l
* Created on 2007年1月1日, 下午5:01 b_ JWnh
* I{<;;;a
* To change this template, choose Tools | Options and locate the template under F '#^`G9
* the Source Creation and Management node. Right-click the template and choose `
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* Open. You can then make changes to the template in the Source Editor. xA9V$# d|
*/ lWlUWhLnP
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package com.tot.count; 0s!N@ ,T
import java.util.*; ux&:Rw\
/** ) MBS
* "VQ|Ed
* @author MHNe>C-!q
*/ t
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public class CountCache { u#VweXyU
public static LinkedList list=new LinkedList(); 8GW ut=D
/** Creates a new instance of CountCache */ SW=aHM
public CountCache() {} *2#FRA#q
public static void add(CountBean cb){ P#F_>GB
if(cb!=null){ q]+)c2M
list.add(cb); i;avwP<0
} S[.5n]
} TnxU/)
} 9C>ynH
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CountControl.java ^Yr|K
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/* `rq<jtf+
* CountThread.java }8
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* uegb;m
* Created on 2007年1月1日, 下午4:57 :Lc3a$qtx5
* L77EbP`P
* To change this template, choose Tools | Options and locate the template under #Wq#beBb
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. 3f,u}1npa*
*/ {NY]L==H
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package com.tot.count; ny~W]1
import tot.db.DBUtils; T7ki/hjRb
import java.sql.*; G ;jF9i
/** rBS2>?
* ]'E}
* @author 9yDFHz w
*/ p/4S$
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public class CountControl{ ,?fN#gc :
private static long lastExecuteTime=0;//上次更新时间 rQ
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 FQQ@kP$.
/** Creates a new instance of CountThread */ `TAcZl=8
public CountControl() {} 6l<1A$BQ
public synchronized void executeUpdate(){ I=K[SY,]9
Connection conn=null; L[1d&d!p
PreparedStatement ps=null; OAY8,C=M
try{ oAC^4-Ld
conn = DBUtils.getConnection(); i@Vs4E[b
conn.setAutoCommit(false); U* 4{"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); &1oaZY w
for(int i=0;i<CountCache.list.size();i++){ o;*]1
CountBean cb=(CountBean)CountCache.list.getFirst(); %OuX`w=
CountCache.list.removeFirst(); )2#vhMpdN
ps.setInt(1, cb.getCountId()); .r(^h/IF
ps.executeUpdate();⑴ h1E
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//ps.addBatch();⑵ FBcm;cjH
} M,ppCHy/$
//int [] counts = ps.executeBatch();⑶ ?C
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conn.commit(); TJE%
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}catch(Exception e){ {$3j/b
e.printStackTrace(); Wf_CR(
} finally{ 4@ =
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try{ 4VC/-.At
if(ps!=null) { 9armirfV'P
ps.clearParameters(); ;Sy/N||
ps.close(); z( *]'Y
ps=null; Jm%mm SYK
} 4Fh&V{`W
}catch(SQLException e){} R9bhC9NP
DBUtils.closeConnection(conn); <r0.ppgY
} TLXhE(o|o
} hyM'x*
public long getLast(){ F
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return lastExecuteTime; _`slkwP.
} d\\r_bGW
public void run(){ bx;yHIRb
long now = System.currentTimeMillis(); ?VUgwP_=
if ((now - lastExecuteTime) > executeSep) { ,9F*96
//System.out.print("lastExecuteTime:"+lastExecuteTime); c{^i$
//System.out.print(" now:"+now+"\n"); E`Q;DlXv>
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 7&=-a|k~
lastExecuteTime=now; p| Vmdnb
executeUpdate(); ;HR 6X
} VjC*(6<Gj
else{ te4F"SEf
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /A0 [_
} h=!M6yap<
} :
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} P"oYC$
//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 f<'n5}{RO0
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类写好了,下面是在JSP中如下调用。 E(7@'d{o
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<% B{[f}h.n
CountBean cb=new CountBean(); R|nEd/'<
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ~?2rGE
CountCache.add(cb); #Tup]czO
out.print(CountCache.list.size()+"<br>"); /A%om|+Gq
CountControl c=new CountControl(); ?s1u#'aO
c.run(); s*aH`M7^0
out.print(CountCache.list.size()+"<br>"); f37ji
%>