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: &$m=^
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CountBean.java CO:*x,6au
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/* U6juS/
* CountData.java }O.LPQ0
* VR4E
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* Created on 2007年1月1日, 下午4:44 :'d76pM-
* emv ;m/&8
* To change this template, choose Tools | Options and locate the template under (|<h^]
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* the Source Creation and Management node. Right-click the template and choose Bw3F7W~l
* Open. You can then make changes to the template in the Source Editor. p;qRm}
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*/ gHi~nEH
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package com.tot.count; D|TLTF"
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/** GB<R7J
* zP:~O
* @author e{fZ}`=7y
*/ W>Mse[6`c
public class CountBean { \;-=ODC
private String countType; J4gI=@e
int countId; n2n00%Wu[
/** Creates a new instance of CountData */ #"Eks79s
public CountBean() {} S)"##-~`T
public void setCountType(String countTypes){ YKP=0 j3,
this.countType=countTypes; |?x^8e<*
} 7$+P|U
public void setCountId(int countIds){ >oft :7p
this.countId=countIds; e=gboR
} z}>4,d
public String getCountType(){ w~<FG4@LU
return countType; -l-AToO4
} =<[7J]%
public int getCountId(){ t/JOERw
return countId; jOBY&W0r
} ljup#:n
} \R8 6;9ov
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CountCache.java >vQ6V'F
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/* kU#:I9PO
* CountCache.java f\h%; X
* ,dHP`j ?
* Created on 2007年1月1日, 下午5:01 [#7y[<.P
* lir&e
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* To change this template, choose Tools | Options and locate the template under D3%l4.h
* the Source Creation and Management node. Right-click the template and choose T@(6hEmP,
* Open. You can then make changes to the template in the Source Editor. PSW#^o
*/ R'G'&H{N
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package com.tot.count; <9@&oN+T
import java.util.*; "0|BoG
/** m9#}X_&x
* X,>(Y8
* @author U:qF/%w
*/ ?N4A9W9
public class CountCache { ]dd[WHA
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ UUl*f!&
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public CountCache() {} jEZ
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public static void add(CountBean cb){ &nQRa?3,
if(cb!=null){ mYjf5
list.add(cb); 5\VxXiy0
} %z1{Kus
} z8b
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} +``>,O6
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CountControl.java :tKbz
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/* LPq2+:JpS
* CountThread.java DXKyRkn6e
* Ip>^O/}$1
* Created on 2007年1月1日, 下午4:57 h=hoV5d@
* DeA @0HOxh
* To change this template, choose Tools | Options and locate the template under }g}6qCv7
* the Source Creation and Management node. Right-click the template and choose 3nwz<P
* Open. You can then make changes to the template in the Source Editor. !loO%3_)
*/ ]a)IMIh;
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package com.tot.count; PM@XtL7J
import tot.db.DBUtils; j\!
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import java.sql.*; f](I.lm:
/** !0b%Jh
* ?hKm&B;d
* @author 6%>/og\%
*/ _~ v-:w
public class CountControl{ w-lrnjs
private static long lastExecuteTime=0;//上次更新时间 ^Ss<X}es-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !@( M_Z'
/** Creates a new instance of CountThread */ 77``8,
public CountControl() {} 6!Qknk$
public synchronized void executeUpdate(){ P2>:p%Z
Connection conn=null; zgK;4
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PreparedStatement ps=null; 8AryIgy>@
try{ D^nxtuT*
conn = DBUtils.getConnection(); 658\#x8|
conn.setAutoCommit(false); ja?s@Y}-9s
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); VW {,:Ya
for(int i=0;i<CountCache.list.size();i++){ .XIr?>G
CountBean cb=(CountBean)CountCache.list.getFirst(); EVG"._I@
CountCache.list.removeFirst(); `%uK0qw"
ps.setInt(1, cb.getCountId()); l7ZB3'
ps.executeUpdate();⑴ (JWv *p
//ps.addBatch();⑵ @2u#93Y
} D{>\-]\
//int [] counts = ps.executeBatch();⑶ N50fL
conn.commit(); sqT^t!
}catch(Exception e){ 6Hda]y
e.printStackTrace(); RXM}hqeG
} finally{ am2a#4`
try{ A&NqQ
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if(ps!=null) { 6>s=CiZB
ps.clearParameters(); jSB'>m]
ps.close(); 1ADv?+j)A/
ps=null; ^L ]B5,}-
} N^lAG"Jao[
}catch(SQLException e){} wajZqC2yg
DBUtils.closeConnection(conn); M</Wd{.g"
} p/N 62G
} +SyUWoM
public long getLast(){ 4 HW;
return lastExecuteTime; )Xp Vu
} J=@xAVBc
public void run(){ 8|6~o.B.G
long now = System.currentTimeMillis(); B7|c`7x(
if ((now - lastExecuteTime) > executeSep) { -rO*7HO
//System.out.print("lastExecuteTime:"+lastExecuteTime); kAeNQRjR
//System.out.print(" now:"+now+"\n"); KYf;_C,$
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); fL2^\dB;
lastExecuteTime=now; !f`5B( @
executeUpdate(); g#}tm<
} 9Yn)t#G'`F
else{ y=#j`MH{>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); W]zwghxH
} .ots?Ns
} w
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} z#RuwB+
//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 ~?CS_B *
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类写好了,下面是在JSP中如下调用。 3+%nn+m
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<% ;7L ;
CountBean cb=new CountBean(); =D5wqCT(Q
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); S_$nCyaH2
CountCache.add(cb); eKyqU9
out.print(CountCache.list.size()+"<br>"); r,0@~;zA
CountControl c=new CountControl(); 8A!'I<S1
c.run(); 2Y$
out.print(CountCache.list.size()+"<br>"); *y?[<2"$
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