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: )CD4k:bm
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CountBean.java &'TZU"_
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/* *GH`u*C_
* CountData.java 64fa0j~<*M
* wa\Yc,R
* Created on 2007年1月1日, 下午4:44 }~DlOvsq
* 8iGS=M
* To change this template, choose Tools | Options and locate the template under ^<}9#q/rt
* the Source Creation and Management node. Right-click the template and choose .D!0$W mOZ
* Open. You can then make changes to the template in the Source Editor. iVu
*/ ?\"GT] 5D
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package com.tot.count; |-a5|3
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/** GL-v</2'U
* Tvqq# ;I
* @author #>iBu:\J
*/ zo6|1xq
public class CountBean { -K eoq
private String countType; B52n'.
int countId; Q3[MzIk 4
/** Creates a new instance of CountData */ (0dy,GRN
public CountBean() {} Iv+JEuIi
public void setCountType(String countTypes){ I!eu|_cF
this.countType=countTypes; zisf8x7^W
} '9@S
public void setCountId(int countIds){ p!B&&)&db
this.countId=countIds; v3PtiKS
} BbsgZ4
public String getCountType(){ 55q!2>Jh.
return countType; Heh.CD)Q
} =z^2KH
public int getCountId(){ m#1>y}
return countId; !xk`oW
} .8e]-^Z
} ])OrSsV}
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CountCache.java 7+
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/* \]<eLw-v
* CountCache.java *U>"_h T0
* @n2Dt d
* Created on 2007年1月1日, 下午5:01 fE`p
* yC \dM1X
* To change this template, choose Tools | Options and locate the template under 6<1
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* the Source Creation and Management node. Right-click the template and choose sjGy=d{:oL
* Open. You can then make changes to the template in the Source Editor. vz6No%8X
*/ 4fauI%kc
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package com.tot.count; vT@*o=I
import java.util.*; wN
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/** *$e1Bv6
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* !]f80z
* @author =z>d GIT1
*/ `A\,$(q+
public class CountCache { h4p<n&)F
public static LinkedList list=new LinkedList(); '3<T~t
/** Creates a new instance of CountCache */ Z9wKjxu+
public CountCache() {} de=){.7Y
public static void add(CountBean cb){ ^AhV1rBB
if(cb!=null){ ~:FF"T>
list.add(cb); xVxN
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} #qLsAw--Q
} mrmm@?
} |\.:h":!0~
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CountControl.java H(?)v.%
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/* [nc-~T+Mo
* CountThread.java ca=sc[ $+
* R?{f:,3R
* Created on 2007年1月1日, 下午4:57 r=6N ZoZ
* elJ?g
&"
* To change this template, choose Tools | Options and locate the template under [#@\A]LO
* the Source Creation and Management node. Right-click the template and choose i+q tL3
* Open. You can then make changes to the template in the Source Editor. :;
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*/ 4Jn+Ot.,d
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package com.tot.count; E)3Ah!
import tot.db.DBUtils; e5AZU7%.
import java.sql.*; \LG0
/** IA%|OVAfF
* ~=GwNo_
* @author P2Jo^WS
*/ RGgePeaw
public class CountControl{ 8Z|A'M
private static long lastExecuteTime=0;//上次更新时间 p!>5}f6
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 <-6f}wN
/** Creates a new instance of CountThread */ knn9s0'Q
public CountControl() {} }~NM\rm
public synchronized void executeUpdate(){ Nl]_Ie6
Connection conn=null; k"3@G?JY
PreparedStatement ps=null; ;!S i_b2
try{ @.&KRAZ
conn = DBUtils.getConnection(); 8n/8uRIR
conn.setAutoCommit(false); 9dVHh?E
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); lvAKL>qX
for(int i=0;i<CountCache.list.size();i++){ E3LEeXcLS
CountBean cb=(CountBean)CountCache.list.getFirst(); %W}YtDf\
CountCache.list.removeFirst(); hbdB67,
ps.setInt(1, cb.getCountId()); Mfn^v:Q#
ps.executeUpdate();⑴ T)MX]T
//ps.addBatch();⑵ {S@gjMuN
} s"UUo|hM
//int [] counts = ps.executeBatch();⑶ ++sbSl)Q
conn.commit(); BT)PD9CN(
}catch(Exception e){ WA6reZ
e.printStackTrace(); K
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} finally{ |.KB
try{ ).)^\
if(ps!=null) { CJjT-(a
ps.clearParameters(); A^c
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ps.close(); 8-_atL
ps=null; .],:pL9d
} >*MGF=.QG
}catch(SQLException e){} HV&i! M@T
DBUtils.closeConnection(conn); U5
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} XuoyB{U
} ;V?3Hwl
public long getLast(){ 2FN E ;y(
return lastExecuteTime; $D='NzE/
} *ESi~7;#
public void run(){ ]GT+UX
long now = System.currentTimeMillis(); >*/:"!u
if ((now - lastExecuteTime) > executeSep) { }Ug$d>\
//System.out.print("lastExecuteTime:"+lastExecuteTime); +~>cAWZq_
//System.out.print(" now:"+now+"\n"); G#Kw6
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1Ep7CV-n}
lastExecuteTime=now; SoWMP2/
executeUpdate(); n-9a0_{k
} uZTbJ3$$
else{ 2KlVj]!7
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &^`[$LtYd
} shD4";8*@
} :q >)c]
} Quwq_.DU
//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 J`4V\D}n
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类写好了,下面是在JSP中如下调用。 bE,#,
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<% .,sbqL
CountBean cb=new CountBean(); O5MV&Zb(
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "574%\#4z
CountCache.add(cb); 0Bt>JbGs4
out.print(CountCache.list.size()+"<br>"); YSzC's[
CountControl c=new CountControl(); rB-R(2
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c.run(); N1}r%!jk/
out.print(CountCache.list.size()+"<br>"); )(OGo`4Qz
%>