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: YyTSyP4
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CountBean.java TUHi5K
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/* A|L 8P
* CountData.java slg ]#Dy
* HPb]Zj
* Created on 2007年1月1日, 下午4:44 "I=\[l8t
* t5'V6nv
* To change this template, choose Tools | Options and locate the template under TjQvAkT
* the Source Creation and Management node. Right-click the template and choose % z#f.Ql
* Open. You can then make changes to the template in the Source Editor. = M]iIWQ@`
*/ UB 6mqjPK
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package com.tot.count; &VV~%jl;k
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/** ccLq+a|
* 9G{;?c
* @author a@\D$#2r
*/ Pu"R,a
public class CountBean { ow0!%|fO
private String countType; rS4@1`/R
int countId; vG;zJ#c
/** Creates a new instance of CountData */ IkrF/$r
public CountBean() {} hGbj0
public void setCountType(String countTypes){ VQ0fS!5'
this.countType=countTypes; +hE(Ra#
} hSFn8mpXT
public void setCountId(int countIds){ ax{ ;:fW
this.countId=countIds; _~rI+l A
} RRGWC$>?
public String getCountType(){ ]J:1P`k.
return countType; W?eu!wL#p
} } ~"hC3w
public int getCountId(){ 0pJ
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return countId; ZTU&,1Y ;
} rAs,X
} 2Fz|fW_
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CountCache.java (tCUlX2
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/* #% of;mJv
* CountCache.java H|ER
* srYJp^sC
* Created on 2007年1月1日, 下午5:01 7ULqo>j
* -K
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* To change this template, choose Tools | Options and locate the template under [Z~ 2
* the Source Creation and Management node. Right-click the template and choose ~BDu$
* Open. You can then make changes to the template in the Source Editor. n Ps7c %
*/ /F4pb]U!*
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package com.tot.count; [74F6Qp
import java.util.*; H(Q.a=&4!p
/** w.lAQ5)I%\
* =xNv\e
* @author /Nr*`l
*/ hgLj<
public class CountCache { 'yV?*a
public static LinkedList list=new LinkedList(); b8%C*r7
/** Creates a new instance of CountCache */
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public CountCache() {} ^-rfvc
public static void add(CountBean cb){ qwK2WE%T
if(cb!=null){ \EKU*5\Hp>
list.add(cb); CBDG./
} {5d9$v7k4
} rQEyD
} 5w\fSY
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CountControl.java K{ \;2M
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/* <)\y#N
* CountThread.java 7lS#f1E
* G NS`.fS
* Created on 2007年1月1日, 下午4:57 {@<J_A
* # [e
* To change this template, choose Tools | Options and locate the template under w,O,W[C
* the Source Creation and Management node. Right-click the template and choose quvanxV-L
* Open. You can then make changes to the template in the Source Editor. Up:<=Kgci
*/ =56T{N
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package com.tot.count; ALEnI@0
import tot.db.DBUtils; ?d4m!HgR
import java.sql.*; )@~J
/** R-Z~V
* e#,~,W.H
* @author ]$p{I)d&
*/ P7
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public class CountControl{ OiAJ[L
private static long lastExecuteTime=0;//上次更新时间 =1P6Vk
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 h Xb%;GL
/** Creates a new instance of CountThread */ Qfky_5R\
public CountControl() {} T]j.=|,d
public synchronized void executeUpdate(){ Wd0[%`dq
Connection conn=null; Yp0/Ab(v
PreparedStatement ps=null; FSRm|
try{ D;I6Q1I
conn = DBUtils.getConnection(); 0W3i()
conn.setAutoCommit(false); >(y<0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); gtYAHi
for(int i=0;i<CountCache.list.size();i++){ T \CCF
CountBean cb=(CountBean)CountCache.list.getFirst(); >Bs#Xb_B]
CountCache.list.removeFirst(); %lX%8Z$v
ps.setInt(1, cb.getCountId()); ;SwMu@tg
ps.executeUpdate();⑴ -QyhwG=
//ps.addBatch();⑵ CiR%Ujf
} sHc Td>xS
//int [] counts = ps.executeBatch();⑶ ]`bQW?
conn.commit(); 2kv7UU#q2
}catch(Exception e){ `)qVF,Z}
e.printStackTrace(); PlYm&
} finally{ oG7q_4+&
try{ wBQF~WY
if(ps!=null) { *xE,sj+(
ps.clearParameters(); >|6iR%"f#
ps.close(); U:MPgtwe
ps=null; G60R9y47c
} ork=`};
}catch(SQLException e){} AW#<i_Ybf
DBUtils.closeConnection(conn); XyMG.r-,
} x!_<z''
} 4lqH8l.
public long getLast(){ /)xlJUq
return lastExecuteTime; QZX~T|Ckv
} N$xtHtz8"
public void run(){ SxK:]Aw
long now = System.currentTimeMillis(); \uME+NF
if ((now - lastExecuteTime) > executeSep) { }Z
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//System.out.print("lastExecuteTime:"+lastExecuteTime); Fkf97Oi
//System.out.print(" now:"+now+"\n"); BYY RoE[P
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); bu&t'?zx!
lastExecuteTime=now; aF|d^
executeUpdate(); `z0{S!
} c}[+h5
else{ 5/gDK+%4D(
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); dq IlD!
} (~)%Fo9X"
} &TG5rUUg
} 7O`o ovW$
//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 ](eN@Xi&@
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类写好了,下面是在JSP中如下调用。 kkvtB<<Y
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<% r-kMLw/)
CountBean cb=new CountBean(); GHF_R,7
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); NZN-^ >
CountCache.add(cb); ^v9|%^ug
out.print(CountCache.list.size()+"<br>"); YpUp@/"
CountControl c=new CountControl(); "4H8A=
c.run(); 5efxEt>U
out.print(CountCache.list.size()+"<br>"); O+=vEp(
%>