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: ]:]w+N%7
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CountBean.java G-T2b,J
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/* .sPa${
* CountData.java :+S~N)0j^
*
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* Created on 2007年1月1日, 下午4:44 -f[95Z3}
* 0(!=N1l
* To change this template, choose Tools | Options and locate the template under G?{uR6s>#
* the Source Creation and Management node. Right-click the template and choose I9r> 3?
* Open. You can then make changes to the template in the Source Editor. e#uF?v]O
*/ |S VL%agZ
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package com.tot.count; w8AHs/'r
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/** h)C`w'L
* OOX}S1lA
* @author 4^BHJOvs
*/ NA8$G|.?
public class CountBean { T
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private String countType; mOi 8W,2
int countId; {BJn9B
/** Creates a new instance of CountData */ K0?:?>*b#
public CountBean() {} f9&po2Pzf
public void setCountType(String countTypes){ o4pe>hn
this.countType=countTypes; =arrp:
} olf7L%
public void setCountId(int countIds){ !"x&tF
this.countId=countIds; 7j L.\O
} Uu3<S
public String getCountType(){ DWRq \`P
return countType; HOAgRhzE
} y]ZujfW7
public int getCountId(){ .EoLJHL
}
return countId; vwQ6=
} 7~Md6.FtM
} %g*AGu`
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CountCache.java HBnnIbEtF'
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/* 5S?+03h~
* CountCache.java [S!_ubP5
* "Dwaq*L
* Created on 2007年1月1日, 下午5:01 PG/xX
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* d$` NApr
* To change this template, choose Tools | Options and locate the template under eyGY8fF8$
* the Source Creation and Management node. Right-click the template and choose ]p2M!N,?
* Open. You can then make changes to the template in the Source Editor. ,] ,dOIOwn
*/ (>\w8]
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package com.tot.count; -F| C6m!
import java.util.*; :Vf :_;
/** >A;9Ee"&
* /?j
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* @author Lk|%2XGO&
*/ AlRng&o~
public class CountCache { IvyBK]{|
public static LinkedList list=new LinkedList(); UjU*`}k3
/** Creates a new instance of CountCache */ tZ]/?+1G
public CountCache() {} }[OOkYF#r
public static void add(CountBean cb){ zLiFk<G@Xi
if(cb!=null){ 7R=cxD&
list.add(cb); sh %snLw
} kW@,P.88
} gjVKk
} )N4_SA
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CountControl.java _ *O^|QbM
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/* MdOQEWJ$|
* CountThread.java fc#zhp5bX
* ,1+)qv#|i
* Created on 2007年1月1日, 下午4:57
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* 2%Y]M%P
* To change this template, choose Tools | Options and locate the template under AI&Bv
* the Source Creation and Management node. Right-click the template and choose T~rPpi&
* Open. You can then make changes to the template in the Source Editor. C&vUZa[p
*/ Q,mmHw.`J
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package com.tot.count; 3i'L5f67
import tot.db.DBUtils; Xn'{g
import java.sql.*; 26,!HmtC
/** CcZ\QOet&C
* lklMdsIdj
* @author crt
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*/ Sb&[V>!2^
public class CountControl{ #;32(II
private static long lastExecuteTime=0;//上次更新时间 ']hB_4v
private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ HNRZ59Yyq
public CountControl() {} X;I;CZ={
public synchronized void executeUpdate(){ *c+Kqz-
Connection conn=null; F`$V H^%V
PreparedStatement ps=null; KU> $=Rd
try{ <"g ^V
conn = DBUtils.getConnection(); ;oQ*gd
conn.setAutoCommit(false); %!G]H
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); XJ|CC.]1u
for(int i=0;i<CountCache.list.size();i++){ jQp7TdvLE$
CountBean cb=(CountBean)CountCache.list.getFirst(); 2?9SM@nAY
CountCache.list.removeFirst(); EVW{!\8[
ps.setInt(1, cb.getCountId()); $Xf gY1S
ps.executeUpdate();⑴ 9w Pc03a
//ps.addBatch();⑵ SG{> t*E
} ;L5'3+U
//int [] counts = ps.executeBatch();⑶ u2SnL$A7
conn.commit(); #l6L7u0~wC
}catch(Exception e){ (CRY$+d
e.printStackTrace(); vPn( ~d_
} finally{ *.UM[Wo
try{ 6p
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if(ps!=null) { yu'2
ps.clearParameters(); <303PPX^6
ps.close(); d+_wN2
ps=null; s 9,?"\0Zm
} "-'w,g
}catch(SQLException e){} Efm37Kv5l
DBUtils.closeConnection(conn); wr/Z)e =^3
} meHAa`
} ]E1aIt
public long getLast(){ 0B^0,d(s
return lastExecuteTime; CF`tNA3fxm
} Lzzf`jN]
public void run(){ ;hz"`{(JY
long now = System.currentTimeMillis(); <|_/i/H
if ((now - lastExecuteTime) > executeSep) { }vRs n-E@
//System.out.print("lastExecuteTime:"+lastExecuteTime); >bia
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//System.out.print(" now:"+now+"\n"); xHv<pza:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 'J (4arN
lastExecuteTime=now; jJc?/1 jv
executeUpdate(); ;~Ke5os=s
} *<yKT$(+_
else{ em
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); AR i_m
} fA!uSqR$V
} .u3!%{/v(c
} wz-9+VN6
//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 #:{Bd8PS
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类写好了,下面是在JSP中如下调用。 36154*q
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<% qm-G=EX
CountBean cb=new CountBean(); x[+t
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); NGD?.^ (G
CountCache.add(cb); B{ wx"mK
out.print(CountCache.list.size()+"<br>"); Vd2bG4*=
CountControl c=new CountControl(); fZ2>%IxG}
c.run(); P;D)5yP092
out.print(CountCache.list.size()+"<br>"); }ZMbTsm
%>