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: xq<3*Bcw
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CountBean.java `HO_t ek
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/* _>k&M7OU4
* CountData.java ?0%3~E`l:
* A)j',jE&1
* Created on 2007年1月1日, 下午4:44 xS>d$)rIj
* 2uln)]
* To change this template, choose Tools | Options and locate the template under 4,)EG1
* the Source Creation and Management node. Right-click the template and choose &ap&dM0@%a
* Open. You can then make changes to the template in the Source Editor. H/?@UJ5m
*/ RL|d-A+;
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package com.tot.count; a?dUJt
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/** yJRqX]MLA
* !`h^S)$
* @author q<Sb>M/\,
*/ NZW)$c'
public class CountBean { qjrl$[`X:
private String countType; CNkI9>L=W`
int countId; (<ZpT%2
/** Creates a new instance of CountData */ KyQd6 1
public CountBean() {} 4J9VdEKk
public void setCountType(String countTypes){ )4tOTi[
this.countType=countTypes; d(X/N2~g
} HkL`-
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public void setCountId(int countIds){ vv
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this.countId=countIds; |3{"ANmm'
} WNmG'hlA
public String getCountType(){ |@*3
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return countType; nd4Z5=X
} fb*h.6^y9
public int getCountId(){ ZCC T
return countId; t|jp]Vp
} jo}yeGbU
} z?I"[M
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CountCache.java Ww&r
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/* JLn)U4>z w
* CountCache.java Krw'|<
* <<M1:1
* Created on 2007年1月1日, 下午5:01 s'4%ZE2Dr
* Zk:_Yiki&
* To change this template, choose Tools | Options and locate the template under qvs&*lBY
* the Source Creation and Management node. Right-click the template and choose x=VLTH/oo
* Open. You can then make changes to the template in the Source Editor. RoLN#
*/ 089 <B& <
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package com.tot.count; w}WfQj
import java.util.*; =v:}{~M^$
/** 2K
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* Mc@_[q!xY?
* @author 6F8TiR&
*/ vi;yT.
public class CountCache { pt_]&3\e
public static LinkedList list=new LinkedList(); 3o^~6A
/** Creates a new instance of CountCache */ ~LF1$Cai
public CountCache() {} rf=oH
}
public static void add(CountBean cb){ %F2T`?t:
if(cb!=null){ 57jDsQAj
list.add(cb); =_=0l+\}
} >z|bQW#2
} zb,YYE1
} i[4t`v'Dk
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CountControl.java K3.z>.F'h
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/* uGU-MC*
* CountThread.java >v'@p
* Z/e^G f#i
* Created on 2007年1月1日, 下午4:57 %$6?em_
* u/.# zn@9h
* To change this template, choose Tools | Options and locate the template under EL^j}P
* the Source Creation and Management node. Right-click the template and choose Ov~vK\
* Open. You can then make changes to the template in the Source Editor. "UUoT
*/ HXb^K
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package com.tot.count; OD6dMql
import tot.db.DBUtils; 9 Eqv^0u
import java.sql.*; <El!,UBq<
/** qE*h UzA
* Txa
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* @author AvZOR
*/ %zYTTPLZ
public class CountControl{ SNrX(V::z
private static long lastExecuteTime=0;//上次更新时间 Aj{G=AT
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :qvA'.L/;z
/** Creates a new instance of CountThread */ R+5yyk\
public CountControl() {} ~sVbg$]\ G
public synchronized void executeUpdate(){ ^5q}M'
Connection conn=null; )CoJ9PO7
PreparedStatement ps=null; TdL/tg!
try{ y3Ul}mVhA
conn = DBUtils.getConnection(); wJg&OQc9
conn.setAutoCommit(false); C
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); l(Y\@@t1
for(int i=0;i<CountCache.list.size();i++){ X3j|J/
CountBean cb=(CountBean)CountCache.list.getFirst(); [!j;jlh7},
CountCache.list.removeFirst(); 9/PX~j9O?
ps.setInt(1, cb.getCountId()); 30{+gYA
ps.executeUpdate();⑴ %*^s%NI
//ps.addBatch();⑵ @@5JuI-!
} *t bgIW+h
//int [] counts = ps.executeBatch();⑶ 7b*9
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conn.commit(); h3(B7n7
}catch(Exception e){ gJg%3K~,
e.printStackTrace(); $xK(bc'{
} finally{ , GMuq_H
try{ 49Hgq/uO
if(ps!=null) { A"wso[{
ps.clearParameters(); SN5Z@kK
ps.close(); *qKf!&
ps=null; =zRjb>
} f!bGH-.r5
}catch(SQLException e){} mMtva}=*
DBUtils.closeConnection(conn); 6.M!WK{+
} ch)#NHZ9F
} DcsQ 6
public long getLast(){ B&sa|'0U
return lastExecuteTime; 9=9R"X>L
} LDbo=w
public void run(){ OyATb{`'
long now = System.currentTimeMillis(); yJ2A!id
if ((now - lastExecuteTime) > executeSep) { ,ik\MSS
//System.out.print("lastExecuteTime:"+lastExecuteTime); )AXa.y
//System.out.print(" now:"+now+"\n"); 2$O6%0
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); :9W)CwZ)V
lastExecuteTime=now; Wl{wY,u
executeUpdate(); kj@m5`G
} :o_6
else{ zvKypx
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); z<u@::
} v;:. k,E0
} V/t-
} *?!A
//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 6D29s]h2
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类写好了,下面是在JSP中如下调用。 0kL
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<% eXQzCm
CountBean cb=new CountBean(); [p96H)8YU
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }^ZPah
CountCache.add(cb); ca"20NQ)
out.print(CountCache.list.size()+"<br>"); Y4)=D@JI
CountControl c=new CountControl(); 2^fSC`!
c.run(); jEW@~e
out.print(CountCache.list.size()+"<br>"); qViolmDz
%>