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: 18F7;d N8
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CountBean.java I"r*p?
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/* dqcfs/XhP
* CountData.java s@0#w*N
* r6"t`M
* Created on 2007年1月1日, 下午4:44 PX+$Us
* U)N;=gr\
* To change this template, choose Tools | Options and locate the template under B+,Z 3*
* the Source Creation and Management node. Right-click the template and choose o: qB#8X
* Open. You can then make changes to the template in the Source Editor. Wa
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*/ :h" Y >1P
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package com.tot.count; lr=*Ty(V
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/** wuI+$?
* YYN=`ST
* @author uYF_sf
*/ 7n5bI\
public class CountBean { Drc\$<9c@
private String countType; iYR8sg[' #
int countId; PbCXcs
/** Creates a new instance of CountData */ AfyEFnY
public CountBean() {} )0YMi!&j`
public void setCountType(String countTypes){ cSQvP.
this.countType=countTypes; ji:JLvf]%
} >{V]q*[/;Q
public void setCountId(int countIds){ S&FMFXF@
this.countId=countIds; ` O-$qT,_
} @32JMS<
public String getCountType(){ yPKeatH]
return countType; Xrc0RWXB8
} 7\<#z|
public int getCountId(){ c)+IX;q-C
return countId; 0Kq\ oMn
} T-uI CMEf
} 5_#wOz0u$
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CountCache.java ]=7}Y%6
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/* )FYz*:f>&
* CountCache.java mKfT4t
*
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* Created on 2007年1月1日, 下午5:01 =T!iM2
* U8;k6WT|
* To change this template, choose Tools | Options and locate the template under C([TolZ
* the Source Creation and Management node. Right-click the template and choose ]&jXD=a"
* Open. You can then make changes to the template in the Source Editor. |s+y]3-_
*/ C&D!TR!K
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package com.tot.count; YOd0dKe
import java.util.*; Yc&yv
/** }]'Z~5T
* Quqts(Q) +
* @author C5$1K'X@
*/ i.C+{QH
public class CountCache { "o+<
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public static LinkedList list=new LinkedList(); I5
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/** Creates a new instance of CountCache */ 9m/v^
public CountCache() {} r1}YN<+,s
public static void add(CountBean cb){ W^Wr
if(cb!=null){ =bi:<%"
list.add(cb); TkM8GK-3
} q]DV49UK
} C5c@@ch :
} ia?{]!7$
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CountControl.java E.R,'Y;x
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/* Ys|tGU
* CountThread.java .i)
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* <j+DY@*
* Created on 2007年1月1日, 下午4:57 bx#GOK-
* !uL z%~F
* To change this template, choose Tools | Options and locate the template under ZBUEg7c
* the Source Creation and Management node. Right-click the template and choose ~xerZQgc
* Open. You can then make changes to the template in the Source Editor. [Abq("9p\
*/ w^6rgCl
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package com.tot.count; GWsvN&nr
import tot.db.DBUtils; W1dpKv
import java.sql.*; ycz6-kEp
/** )"`(+Ku&c
* ph
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* @author wuRQ
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*/ P-o/ax
public class CountControl{ U-&dn%Sq
private static long lastExecuteTime=0;//上次更新时间 |3<tDq@+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 W<_9*{|E;
/** Creates a new instance of CountThread */ |qnAqzK|
public CountControl() {} aAhXHsZ|26
public synchronized void executeUpdate(){ t6(LO9 Qc
Connection conn=null; [H<![Z1*r
PreparedStatement ps=null; OGpy\0%
try{ ">_<L.,I
conn = DBUtils.getConnection(); %
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conn.setAutoCommit(false); K%h9'}pq>1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); SaceIV%(
for(int i=0;i<CountCache.list.size();i++){ V3r1|{Z(
CountBean cb=(CountBean)CountCache.list.getFirst(); lI~T>Lel2
CountCache.list.removeFirst(); ZfsM($|a
ps.setInt(1, cb.getCountId()); jM]B\cvN
ps.executeUpdate();⑴ h8B:}_Cu
//ps.addBatch();⑵ _IYd^c
} T#KF@8'-
//int [] counts = ps.executeBatch();⑶
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conn.commit(); (&t741DN|
}catch(Exception e){ #;~`+[y?\
e.printStackTrace(); ?-C=_eZJ
} finally{ g?&_5)&
try{ =;Ap+}
if(ps!=null) { s&&8~
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ps.clearParameters(); 5-qk"@E W
ps.close(); v<CZ.-r\j
ps=null; &B?TX.
} 3>asl54
}catch(SQLException e){} O=m_P}K
DBUtils.closeConnection(conn); v%a)nv
} utOATjB.z
} pn"TFapJA
public long getLast(){ Sp/t[\,'
return lastExecuteTime; r{2V`h1/|
} \vwsRT 1
public void run(){ M~/7thP{
long now = System.currentTimeMillis(); R<(kiD\?]
if ((now - lastExecuteTime) > executeSep) { {;mT.[
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9BR/zQ2
//System.out.print(" now:"+now+"\n"); R. :~e
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); $.HZz
lastExecuteTime=now; ,'!x9 `
executeUpdate(); Rn?Yz^
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} 3lr9nBR
else{ u*}[fQ`aF
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); I
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} |p_\pa1&
} ^V6cx2M
} 7 6 nrDE
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 \EI<1B
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类写好了,下面是在JSP中如下调用。 /Q]6"nY
}OZut!_
<% l/*NscYtQ
CountBean cb=new CountBean(); 6="Qwrk
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); OeMI
CountCache.add(cb); vX?MB
out.print(CountCache.list.size()+"<br>"); Lsu_f'p0
CountControl c=new CountControl(); >%6a$r~@
c.run(); ]cQYSN7!SY
out.print(CountCache.list.size()+"<br>"); fG dT2}gd
%>