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: ~m09yc d<
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CountBean.java *Wo$$T
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/* %oL&~6l$
* CountData.java \t(r@qq
* f]6`GsE
* Created on 2007年1月1日, 下午4:44 [W|7r
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* 7te!>gUW
* To change this template, choose Tools | Options and locate the template under ~Z/ `W`
* the Source Creation and Management node. Right-click the template and choose ~JRuMP
* Open. You can then make changes to the template in the Source Editor. 8sjHQ)<
*/ 6l]?%0[*
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package com.tot.count; x^#{2}4u
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/** .dLX'84fY
* e2o9)=y
* @author DW%K'+@M
*/ 1eyyu!
public class CountBean { BG? 2PO{
private String countType; h
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int countId; KA{DN!
/** Creates a new instance of CountData */ GvtI-\h]
public CountBean() {} V5@[7ncVf
public void setCountType(String countTypes){ <l
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this.countType=countTypes; >W]"a3E
} nu%Nt"~[%
public void setCountId(int countIds){ F$y FR
this.countId=countIds; ]fS~N9B
} |
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public String getCountType(){ 4k?JxA)
return countType; ?,e:c XhE2
} !J(,M)p!
public int getCountId(){ LuQ
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return countId; +/lj~5:y
} Q
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} `*9FKs
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CountCache.java M~Dc5\T
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/* Q/`o6xv
* CountCache.java 1xV1#'@[Jd
* ef;="N
* Created on 2007年1月1日, 下午5:01
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* 19{?w6G<k
* To change this template, choose Tools | Options and locate the template under b/}0
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* the Source Creation and Management node. Right-click the template and choose &r%^wfp
* Open. You can then make changes to the template in the Source Editor. r9'H7J
*/ <).qe Z
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package com.tot.count; WWD@rn sVf
import java.util.*; moI<b\G@
/** _7HJ'
* ^52R`{
* @author )g^Ewzy^X
*/ ly5L-=Xb
public class CountCache { M@[gT?mv1
public static LinkedList list=new LinkedList(); $
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/** Creates a new instance of CountCache */ q8v!{Os+#
public CountCache() {} Guc^gq}
public static void add(CountBean cb){ cDyC&}:f
if(cb!=null){ J|8YB3K,
list.add(cb); N!&VBx^z
} zvC,([
} "A`'~]/hE
} :%]R x&08
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CountControl.java 19`0)pzZ*P
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/* ' *C)S
* CountThread.java \eN/fTPm
* 0DT2qM[,
* Created on 2007年1月1日, 下午4:57 Px&Mi:4tG
* boB{Y 7gO4
* To change this template, choose Tools | Options and locate the template under mU>*NP(L
* the Source Creation and Management node. Right-click the template and choose kakWXGeR
* Open. You can then make changes to the template in the Source Editor. 3H%WB|
*/ IH:Cm5MV
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package com.tot.count; TL:RB)- <
import tot.db.DBUtils; 8gm[Q[
import java.sql.*; SntYi0,`
/** *heQ@ww
* D];([:+4
* @author cSDCNc*%
*/ Z}S tA0F_
public class CountControl{ ,OAWGFKOp
private static long lastExecuteTime=0;//上次更新时间 ZWEzL$VWi
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,Gx=e!-N5
/** Creates a new instance of CountThread */ "g[UX{L
public CountControl() {} _I5+o\;1
public synchronized void executeUpdate(){ xF+x I6
Connection conn=null; rWmi 'niu
PreparedStatement ps=null; M_I\:Q
try{ K%Ml2V
conn = DBUtils.getConnection(); g<3>7&^
conn.setAutoCommit(false); 9DKB+K.1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >;?97'M
for(int i=0;i<CountCache.list.size();i++){ <2A'
CountBean cb=(CountBean)CountCache.list.getFirst(); 7^X_tQf
CountCache.list.removeFirst(); W4a20KM2
ps.setInt(1, cb.getCountId()); 9oz)E>K4f
ps.executeUpdate();⑴ sg\jC#
//ps.addBatch();⑵ nK=V`
} 8#B;nyGD1I
//int [] counts = ps.executeBatch();⑶ 2@rc&Tx
conn.commit(); ~h+3WuOv
}catch(Exception e){ IDZn,^
e.printStackTrace(); ;r}<o?'RM
} finally{ xc3Q7u!|
try{ X[6z
if(ps!=null) { a a]v7d
ps.clearParameters(); JpiKZG@L
ps.close(); cXH?'q'vZ
ps=null; 8 EH3zm4
} bc-}Qn
}catch(SQLException e){} z8MYgn7
DBUtils.closeConnection(conn); _?<Fc8F
} zf#&3K 'k
} r6G)R+ #
public long getLast(){ 4{E=wg^p
return lastExecuteTime; IQ8AsV&'C
} /9Xf[<
public void run(){ !I&Sy]G
long now = System.currentTimeMillis(); YgDasKFm'
if ((now - lastExecuteTime) > executeSep) { z"`?<A&u
//System.out.print("lastExecuteTime:"+lastExecuteTime); yRDLg
c
//System.out.print(" now:"+now+"\n"); VvKH]>*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1tc9STYR}
lastExecuteTime=now; |JQ05nb
executeUpdate(); cKAl 0_[f"
} na)ceN2h
else{ T94$}- 5/)
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1qF.0
} +^:K#S9U
} 1cega1s3xR
} HR
//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 ysPW<
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类写好了,下面是在JSP中如下调用。
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<% TmiQq'm[b
CountBean cb=new CountBean(); [XK"$C]jHJ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); &5<lQ1
CountCache.add(cb); #$E
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out.print(CountCache.list.size()+"<br>"); ,5:86'p
CountControl c=new CountControl(); 3WS %H17
c.run(); C54)eT6
out.print(CountCache.list.size()+"<br>"); _u;
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%>