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: 'Rn-SD~gIr
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CountBean.java N-M.O:p
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/* 6h;(b2p{
* CountData.java 8)X9abC
* t )zd'[
* Created on 2007年1月1日, 下午4:44 DXiA4ihr=
* %bDxvaftT
* To change this template, choose Tools | Options and locate the template under +.V+@!
* the Source Creation and Management node. Right-click the template and choose 9(N
* Open. You can then make changes to the template in the Source Editor. d.wGO]"
*/ Tc6cBe,
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package com.tot.count; Z+El(f x
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/** {]HiT pn
* =Zq6iMD
* @author JI"/,fK^
*/ y&NqVR=
public class CountBean { M~taZt4
private String countType; )7>GXZG>=
int countId; AByl1)r|
/** Creates a new instance of CountData */ @t9HRL?T~
public CountBean() {} ^PZ[;F40
public void setCountType(String countTypes){ S<i$0p8J;
this.countType=countTypes; rOSov"7
} m-AF&( ;K
public void setCountId(int countIds){ x0
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this.countId=countIds; "I.6/9
} *-T.xo
public String getCountType(){ cE]z Tu?!
return countType; b(*\4n
} E3uu vQ#|
public int getCountId(){ Je6[q
return countId; QL/KY G
} A[Mke
} t?GH
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CountCache.java <Vhd4c
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/* v
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* CountCache.java I=0c\ U}
* \OwF!~&
* Created on 2007年1月1日, 下午5:01 Unk/uk
* @{y'_fw
* To change this template, choose Tools | Options and locate the template under Z.\q$U7'9
* the Source Creation and Management node. Right-click the template and choose ;I>nA6A
* Open. You can then make changes to the template in the Source Editor. NHd@s#@
*/ KL&/Yt
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package com.tot.count; ?@b6(f
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import java.util.*; >yO/p(/;jR
/** vzIo2,/7
* S<nF>JRJa
* @author l/N<'T_G
*/ ZJ/528Ju
public class CountCache { J>Ar(p
public static LinkedList list=new LinkedList(); /q9I^ ztV
/** Creates a new instance of CountCache */ A,~3oQV
public CountCache() {} B7%,D}
public static void add(CountBean cb){ ,!:c6F+
if(cb!=null){ d0aXA+S%
list.add(cb); Qte5E}V`
} =g#PP@X]D!
} ]rG=\>U3~
} bY~K)j
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CountControl.java /@9Q:'P
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/* g NI1W@)
* CountThread.java q[$>\Nfg>B
* ytcLx77`:
* Created on 2007年1月1日, 下午4:57 ;8]HCC@:
* s%jBIeh
* To change this template, choose Tools | Options and locate the template under EG{+Sz
* the Source Creation and Management node. Right-click the template and choose n`5Nf
* Open. You can then make changes to the template in the Source Editor. Wmbc
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*/ x"2p5T7*>
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package com.tot.count; j\uZo.Ot+
import tot.db.DBUtils; ,
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import java.sql.*; L ]')=J+
/** bQaRl=:[:
* 6N@=*0kh-
* @author S@,/$L
*/ )PN8HJAArh
public class CountControl{ @yTu/U
private static long lastExecuteTime=0;//上次更新时间 ZdW+=;/#
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 /$; Z ~^P
/** Creates a new instance of CountThread */ K$S0h-?9]O
public CountControl() {}
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public synchronized void executeUpdate(){ Za@\=}Tt
Connection conn=null; f.g!~wGD
PreparedStatement ps=null; 0LQRQuh1
try{ #}~tTL
conn = DBUtils.getConnection(); } 9@rhW
conn.setAutoCommit(false); ^%\a,~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ,+i^]yF3j
for(int i=0;i<CountCache.list.size();i++){ nDrRK
CountBean cb=(CountBean)CountCache.list.getFirst(); #/qcp|m
CountCache.list.removeFirst(); iA[T'+.Y
ps.setInt(1, cb.getCountId()); fG 2)r
ps.executeUpdate();⑴ Y9abRrK
//ps.addBatch();⑵ +R~]5Rxd
} }u^bTR?3
//int [] counts = ps.executeBatch();⑶ :DH@zR
conn.commit(); `gl?y;xC
}catch(Exception e){ yCjc5d|tT
e.printStackTrace(); <$nPGz)}
} finally{ Q=Q+*oog
try{ d!I%AlV
if(ps!=null) { +k=*AQt^8
ps.clearParameters(); ]@U?hD
ps.close(); lO@-*m$
ps=null; Vz mlKVE
} (u?s@/e:`/
}catch(SQLException e){} 5 H._Q
DBUtils.closeConnection(conn); u$w.'lK
} @5Z|e
} {V[xBL
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public long getLast(){ $
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return lastExecuteTime; U`*we43
} ~D5
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public void run(){ }-[l)<F:
long now = System.currentTimeMillis(); X"Eqhl<t
if ((now - lastExecuteTime) > executeSep) { SrA6}kS
//System.out.print("lastExecuteTime:"+lastExecuteTime); K E\>T:
//System.out.print(" now:"+now+"\n"); XU'(^Y8Imz
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ~vF*&^4Vh
lastExecuteTime=now; |1wZ`wGZ:L
executeUpdate(); ],c0nz^%BR
} @;EQ{d
else{ ;8H&FsR
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); i?_Q@uA~<:
} mLq0;uGL|
} P~(&lu/;P
} aMqt2{f+
//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 i7H([b<_m
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类写好了,下面是在JSP中如下调用。 %[n5mF*`
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<% B+FTkJ0t+G
CountBean cb=new CountBean(); +aL6$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); x.gz sd
CountCache.add(cb); 3g7]$}
out.print(CountCache.list.size()+"<br>"); 1=]#=)+
CountControl c=new CountControl(); $bp'b<jx
c.run(); D u<P^CE
out.print(CountCache.list.size()+"<br>"); #mH28UT
%>