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: |$tF{\
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CountBean.java C,ldi"|
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/* *vNAm(\N
* CountData.java &x (D%+
* =glG |
* Created on 2007年1月1日, 下午4:44 fm#7}Y
* "vYjL&4h
* To change this template, choose Tools | Options and locate the template under <OiH%:G/1
* the Source Creation and Management node. Right-click the template and choose MNh:NFCRA
* Open. You can then make changes to the template in the Source Editor. HZ(giAyjq
*/ di;~$rI!?
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package com.tot.count; mb'{@
5> 81Vhc,
/** "Ml#,kU<T
* DW,Z})9
* @author ZkibfVwe
*/ 9QD+
public class CountBean { ,*[N_[
private String countType; ~- aUw}U
int countId; uKY1AC__
/** Creates a new instance of CountData */ CT\rx>[J.6
public CountBean() {} U+-;(Fh~
public void setCountType(String countTypes){ [+@T"2h2b
this.countType=countTypes; njNqUo>
} (\'lV8}U
public void setCountId(int countIds){ (Ms0pm-#t
this.countId=countIds; >YdLB@
} FrRUAoFO
public String getCountType(){ 5rtE/{A
return countType; \+
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} `OZiN;*|
public int getCountId(){ <\d`}A:&
return countId; dF&@q,
} OSJL,F,
} H ~<.2b
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CountCache.java ;Rxc(tR!n
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/* Yru,YA
* CountCache.java ^%1u3
* ##"
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* Created on 2007年1月1日, 下午5:01 L 'e|D=y
* 4?_^7(%p
* To change this template, choose Tools | Options and locate the template under /BS yanro
* the Source Creation and Management node. Right-click the template and choose Q}^qu6
* Open. You can then make changes to the template in the Source Editor. nbv}Q-C
*/ sZ"(#g;3<
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package com.tot.count; wF-H{C'
import java.util.*; bz`rSp8h
/** eV9,G8
* |/u,6`
* @author w,1*dn
*/ ~'Korxa
public class CountCache { `@&WELFv{
public static LinkedList list=new LinkedList(); EO/TuKt
/** Creates a new instance of CountCache */ 5',&8
public CountCache() {} U_wIx
public static void add(CountBean cb){ :?gp}.
if(cb!=null){ <I{Yyl^
list.add(cb); Om8Sgy?
} Ibv`/8xh
} e=ry_@7
} m*14n_m'
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CountControl.java 2t3)$\ylQp
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/* T9YrB
* CountThread.java `Js"*[z
* nYTPcT4x|
* Created on 2007年1月1日, 下午4:57 ZkF6AF
* PSU}fo
* To change this template, choose Tools | Options and locate the template under xQxq33\
* the Source Creation and Management node. Right-click the template and choose r_Pi)MPc
* Open. You can then make changes to the template in the Source Editor. 5?>ES*
*/
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package com.tot.count; Hw,@oOh.
import tot.db.DBUtils; )D7/[zb^
import java.sql.*; whQJWi=ck
/** ugs9>`fF&
* wu0q.]
* @author dlioa Yc
*/ (~?p`g+I.P
public class CountControl{ n"Wlfd0
private static long lastExecuteTime=0;//上次更新时间 a-NicjV#
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 lPg?Fk7AP
/** Creates a new instance of CountThread */ kK.[v'[>&
public CountControl() {} 5p~hUP]tT
public synchronized void executeUpdate(){ 4i+H(d n
Connection conn=null; rw[Ioyr-
PreparedStatement ps=null; kTm}VTr
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try{ o`Q.;1(Y'
conn = DBUtils.getConnection(); CsN^u H
conn.setAutoCommit(false); [$z-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); f7&9IW`7F^
for(int i=0;i<CountCache.list.size();i++){ ]&X}C{v)G
CountBean cb=(CountBean)CountCache.list.getFirst(); v4,Dt
CountCache.list.removeFirst(); OU<v9`<
ps.setInt(1, cb.getCountId()); !gJw?(8"
ps.executeUpdate();⑴ wv^n#
//ps.addBatch();⑵ $t0JfDd6Ky
} &"^U=f@v
//int [] counts = ps.executeBatch();⑶ TrBW0Bn>p
conn.commit(); JB'XH~4H
}catch(Exception e){ P+DIo7VTX
e.printStackTrace(); 1o?uf,H7O
} finally{ ;*WG9Y(W
try{ -!
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if(ps!=null) { T@a|*.V
ps.clearParameters(); ~nApRC)0
ps.close(); od^ylg>K
ps=null; `i<Z<
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} ?@;#|^k9
}catch(SQLException e){} PJ^qE|X
DBUtils.closeConnection(conn); J|`.d46
} IRTD(7"oyp
} wZWAx
public long getLast(){ ;RYIc0%
return lastExecuteTime; DKF
'*
} IL`=r6\
public void run(){ t8`wO+4@
long now = System.currentTimeMillis(); ;*0?C'h=
if ((now - lastExecuteTime) > executeSep) { I{=Yuc
//System.out.print("lastExecuteTime:"+lastExecuteTime); BAtjYPX'w
//System.out.print(" now:"+now+"\n"); *D.Ajd.G
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^9kx3Pw?8
lastExecuteTime=now; 4eJR=h1
executeUpdate(); (p<pF].
} }b/P\1#z
else{ Nnq1&j"m
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); iUk#hLLC
} zE~Xxp
}
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} PbsxjP
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 D"%>
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类写好了,下面是在JSP中如下调用。 l]OzE-*$b
c=X+uO-
<% m"QDc[^Ge
CountBean cb=new CountBean(); Xt
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ILqBa:J
CountCache.add(cb); c3r`T{Kf
out.print(CountCache.list.size()+"<br>"); AREjS$
CountControl c=new CountControl(); s;$f6X
c.run(); <_#2+7Qs
out.print(CountCache.list.size()+"<br>"); f+8 QAvh
%>