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: .IJgkP)!]
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CountBean.java Fxr$j\bm
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/* =Wj{J.7mf]
* CountData.java O}IRM|r"
* x<%V&<z1g
* Created on 2007年1月1日, 下午4:44 Lk~aMbw#
* }\Mmp+<
* To change this template, choose Tools | Options and locate the template under >'X[*:Cx
* the Source Creation and Management node. Right-click the template and choose 60 z =bd]
* Open. You can then make changes to the template in the Source Editor.
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*/ To"J>:l
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package com.tot.count; wNgS0{}&`
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/** ;K9rE3
* 1Xi.OGl
* @author zn@yt%PCV
*/ +(|6Wv
public class CountBean { JxM[LvVi
private String countType; E}WO?xxv74
int countId; $m-rn'Q
/** Creates a new instance of CountData */ h!L6NS_Q,
public CountBean() {} zU)Ib<$
public void setCountType(String countTypes){ 3r(i=ac0
this.countType=countTypes; H_CX5=Nq^
} ,[{)4J$MV
public void setCountId(int countIds){ u`2[V4=L
this.countId=countIds; b0_Ih6
} $h( B2
public String getCountType(){ "2'pS<|
return countType; U oiXIf_Q
} =,-&h
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public int getCountId(){ aA-gl9
return countId; Uj[E_4h
}
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} igD,|YSK`z
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CountCache.java cKKl\g@}
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/* \%FEQa0u
* CountCache.java ,{br6*E
* -}Iw!p#O3
* Created on 2007年1月1日, 下午5:01 Uxyj\p
* *=X$j~#X
* To change this template, choose Tools | Options and locate the template under *uq}jlD`!
* the Source Creation and Management node. Right-click the template and choose 3bi,9 >%
* Open. You can then make changes to the template in the Source Editor. ?Gq|OT8
*/ mw*BaDN@Q
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package com.tot.count; *N;# _0)/
import java.util.*; 855JAf
/** ,' m<YTF
* *"pf3x6
* @author
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*/ ]EhW
public class CountCache { VkNg Vjg
public static LinkedList list=new LinkedList(); W_E0+
/** Creates a new instance of CountCache */ MZ{gU>K+
public CountCache() {} _8U
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public static void add(CountBean cb){ pUz;e#J|
if(cb!=null){ RnX:T)+o
list.add(cb); ^atX/
} cN5,\I.
} !A\Qwg>
} \MA4>
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CountControl.java dt -=7mz#
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/* bH-QF\>
* CountThread.java cq=ker zQ
* Nx8~Rn
* Created on 2007年1月1日, 下午4:57 H.HXwN/x
* QD}'2{M!
* To change this template, choose Tools | Options and locate the template under \NEXtr`Th
* the Source Creation and Management node. Right-click the template and choose >2[\WF*"X
* Open. You can then make changes to the template in the Source Editor. 1$*ZN4
*/ "0(H! }D
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package com.tot.count; <&+\X6w[
import tot.db.DBUtils; 12yr_
import java.sql.*; SGd[cA
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/** z|o7k;raH
* fU )@Lj1Wo
* @author mP@<UjxI
*/ a}Dx"zl;
public class CountControl{ $X9`~Sv _
private static long lastExecuteTime=0;//上次更新时间 bk-veJR
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 P@m_tA%
/** Creates a new instance of CountThread */ S<f]Y4A&
public CountControl() {} MrW#~S|ED
public synchronized void executeUpdate(){ 3Vu_-.ID
Connection conn=null; $fhb-c3
PreparedStatement ps=null; r{V=)h
try{ K|q5s]4I
conn = DBUtils.getConnection(); 0.9%m7.m
conn.setAutoCommit(false); i58&o@.H<u
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); VuOZZ7y
for(int i=0;i<CountCache.list.size();i++){ F.s*^}L[
CountBean cb=(CountBean)CountCache.list.getFirst(); ^ *{:;F@
CountCache.list.removeFirst(); &.zG?e.
ps.setInt(1, cb.getCountId()); _NfdJ=[Xh
ps.executeUpdate();⑴ \lJCBb+k
//ps.addBatch();⑵ w&vZ$n-|
} BP& T|s
//int [] counts = ps.executeBatch();⑶ ]5V=kNui
conn.commit(); [p+]H?(A
}catch(Exception e){ [IF5Iv\b
e.printStackTrace(); Pp*:rA"N
} finally{ 8gQg#^,(t
try{ [O"9OW'2!B
if(ps!=null) { ScgaWJ
ps.clearParameters(); g H+s)6
ps.close(); 56;^
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ps=null; :6
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} Z?Cl5o&lb
}catch(SQLException e){} 1%v!8$
DBUtils.closeConnection(conn); 8QYP\7}o
} jf`QoK
} y_>l'{w3^
public long getLast(){ n#2tFuPE
return lastExecuteTime; 4@iMGYR9!s
} =N62 ){{
public void run(){ <6
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long now = System.currentTimeMillis(); Z%Kkh2-uh
if ((now - lastExecuteTime) > executeSep) { %j.B/U$
//System.out.print("lastExecuteTime:"+lastExecuteTime); #%~PNki
//System.out.print(" now:"+now+"\n"); (R.l{(A
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); o =oXL2}
lastExecuteTime=now; S,ENbP%0r
executeUpdate(); |XDbf3^6
} E%[2NsOM]
else{ [MQU~+]
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <}\!FuC
} V<:)bG4;d
} iI!MF1
} d@$]/=%
//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 V0rS^SAF
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类写好了,下面是在JSP中如下调用。 ,P%a0\
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<% ,2|(UTv
CountBean cb=new CountBean(); Oc
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); m-<"`:+
CountCache.add(cb); X,]E {
out.print(CountCache.list.size()+"<br>"); LU-,B?1
CountControl c=new CountControl(); c:J;Q){Xz
c.run(); ii3{HJ*C
out.print(CountCache.list.size()+"<br>"); \ah.@s
%>