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: *k62Qz3
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CountBean.java )|xu5.F
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/* FL^ _)`
* CountData.java -&>V.hi7
* Fm0d0j
* Created on 2007年1月1日, 下午4:44 $G9LaD#;M
* AAlc %d/9
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose rM,e$
* Open. You can then make changes to the template in the Source Editor. ,s #~00C|
*/ "dX~J3$
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package com.tot.count; kg]6q T;Y
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/** UpG DLb f^
* 5MB`yRVv
* @author /=m AVA
*/ (yqe4
public class CountBean { C6;2Dd]"N
private String countType; [g/D<g5O
int countId; z_$c_J
/** Creates a new instance of CountData */ YQG<Q
public CountBean() {} i"0Bc{cQ
public void setCountType(String countTypes){ 5p[}<I{
this.countType=countTypes; ~4{q
} "kyCY9)%
public void setCountId(int countIds){ iAu/ t
this.countId=countIds; O@T,!_Zf
} Y7}Tuy dC
public String getCountType(){ 7z4k5d<^_
return countType; o{sv<$
} noxJr/A]
public int getCountId(){ eut2x7Z(c
return countId; o:AfEoH"~
} %;k Hnl
} VO|ECB2e
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CountCache.java 2F:qaz
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/* .d1ff];
* CountCache.java Ds">eNq
* kP
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* Created on 2007年1月1日, 下午5:01 lA5Dag'
* n^4R]9U
* To change this template, choose Tools | Options and locate the template under Ik0g(-d
* the Source Creation and Management node. Right-click the template and choose (?|M'gZ
* Open. You can then make changes to the template in the Source Editor. \"a{\E,{;
*/ aV'bI
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package com.tot.count; ?uq`| 1`
import java.util.*; ApCU|*r)
/** WPL@v+
* xak)YOLRV
* @author Jp=fLo 9
*/ xQu|D>kv87
public class CountCache { 'ZuS
public static LinkedList list=new LinkedList(); y!#-[K:
/** Creates a new instance of CountCache */ rL{R=0
public CountCache() {} !{lH*
public static void add(CountBean cb){ c
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if(cb!=null){ l*1|B3#m!
list.add(cb); e3p|g]
} T$%|=gq
} p\w<~pN[
} al9wNtMT
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CountControl.java )\akIA
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/* 'o-4'
* CountThread.java D@bGJc0
* 0B`X056|"|
* Created on 2007年1月1日, 下午4:57 *S.U8;*Xj
* 5?7AzJl>
* To change this template, choose Tools | Options and locate the template under Du+W7]yCl
* the Source Creation and Management node. Right-click the template and choose %\m"Yi]
* Open. You can then make changes to the template in the Source Editor. ;,&cWz
*/ 3v8LzS3@
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package com.tot.count; Y MX9Z||
import tot.db.DBUtils; !T`oHs
import java.sql.*; dJ"M#X!Zu
/** |THpkfW
* ` =>}*GS
* @author ~bLx2=-"
*/ +=3=% %?C
public class CountControl{ 6X \g7bg
private static long lastExecuteTime=0;//上次更新时间 W;vNmg}mn
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 tk"+ u_u w
/** Creates a new instance of CountThread */ nuce(R
public CountControl() {} X94a
public synchronized void executeUpdate(){ gQn%RPMh
Connection conn=null; :$WO"HfMSn
PreparedStatement ps=null; yKc-:IBb{u
try{ u R0UfKK
conn = DBUtils.getConnection(); c7e,lgG-
conn.setAutoCommit(false); {X!OK3e
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); AFrJzh:V[
for(int i=0;i<CountCache.list.size();i++){ xlI=)ak{
CountBean cb=(CountBean)CountCache.list.getFirst(); <Riz!(G
CountCache.list.removeFirst(); 5C Dk5B_
ps.setInt(1, cb.getCountId()); [4z,hob
ps.executeUpdate();⑴ 'R7 \
//ps.addBatch();⑵ V@
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} n#(pT3&
//int [] counts = ps.executeBatch();⑶ V(7,N(
conn.commit(); z#*.9/y\^R
}catch(Exception e){ :"%/u9<A
e.printStackTrace(); G|wtl(}3
} finally{ QQ(}71U
try{ L+am-k:T~
if(ps!=null) { * ,hhX
psa
ps.clearParameters(); NAR6q{c
ps.close(); /LD3Bb)O
ps=null; t3;Zx+Br
} }%|ewy9|CW
}catch(SQLException e){} J&xZN8jW
DBUtils.closeConnection(conn); s2<!Zb4
} Zy}tZ RG
} l=~!'1@L}
public long getLast(){ YF5}~M ymF
return lastExecuteTime; MEDh
} /F0q8j0
public void run(){ PYkhY;*
long now = System.currentTimeMillis(); M+/G>U
if ((now - lastExecuteTime) > executeSep) { Vj*-E
//System.out.print("lastExecuteTime:"+lastExecuteTime); 5hrI#fpOR
//System.out.print(" now:"+now+"\n"); H"A%mrb
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >e;-$$e
lastExecuteTime=now; ]fyfL|(;
executeUpdate(); V1aP_G-:
} XqTguO'
else{ G/_IY;
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); @oXGa>Ru
} D-gH_ff<]9
} ula-o)S
} gaF6j!p
//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 o<G 9t6~
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类写好了,下面是在JSP中如下调用。 jI-a+LnEm
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<% 7N$2N!I(
CountBean cb=new CountBean(); \-\>JPO~<
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \[MAa:/
CountCache.add(cb); I
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out.print(CountCache.list.size()+"<br>"); y'R}
CountControl c=new CountControl(); nS+Rbhs
c.run(); <:S qMf
out.print(CountCache.list.size()+"<br>"); dOhSqx56
%>