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: tsk)zP,<
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CountBean.java {p,]oOq\
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/* tor!Dl@Mo
* CountData.java A<ynIs<
* P~ &$l2
* Created on 2007年1月1日, 下午4:44 rXHv`ky
* [<KM?\"1<
* To change this template, choose Tools | Options and locate the template under yDGVrc'
* the Source Creation and Management node. Right-click the template and choose GAAm0;
* Open. You can then make changes to the template in the Source Editor. {^N[("`
*/ P67o{EdK
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package com.tot.count; AoyX\iqQ
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/** aCL!]4K84$
* jq!tT%o*B
* @author 4
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*/ YX#-nyK
public class CountBean { I"`M@ %
private String countType; 9VbOQ {8
int countId; {`w;39$+
/** Creates a new instance of CountData */ t2"FXTAq
public CountBean() {} y a_<^O
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public void setCountType(String countTypes){ nqf,4MR
this.countType=countTypes; Ox@P6|m
} ^I+)o1%F
public void setCountId(int countIds){ /:FOPPs
this.countId=countIds; }-@`9(o`)
} %!1Q P[}K
public String getCountType(){ QeK*j/
return countType; @62Mk},9 c
} *Aa?yg:=
public int getCountId(){ -!
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return countId; uDZT_c'Y
} ERN>don2
} 42qYg(tZ
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CountCache.java rX1QMR7?
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/* G}G#i`6o
* CountCache.java j.@\3'
* ,#kIr
* Created on 2007年1月1日, 下午5:01 pt}X>ph{
* wLH] <k
* To change this template, choose Tools | Options and locate the template under nxl[d\ap+n
* the Source Creation and Management node. Right-click the template and choose VZl6t;cn
* Open. You can then make changes to the template in the Source Editor. ^) s2$A:L
*/ >MvDVPi~+
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package com.tot.count; w/ K_B:s
import java.util.*; J`^I./
/** :EA\)@^$R
* 'uxX5k/D@t
* @author Jtk|w[4L
*/ m
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public class CountCache { (#E.`e1#6
public static LinkedList list=new LinkedList(); smDw<slC
/** Creates a new instance of CountCache */ u5%7}<nNi
public CountCache() {} 5EfS^MRf\n
public static void add(CountBean cb){ G@Z?&"
if(cb!=null){
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list.add(cb); v*[.a#1^
} AD<q%pu&H?
} X<%Q"2hW
} mFZ?hOyP.
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CountControl.java 9^p;UA
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/* _n` a`2C|m
* CountThread.java
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* 6Avw-}.7>
* Created on 2007年1月1日, 下午4:57 E!P yL>){
* y7i*s^ys{
* To change this template, choose Tools | Options and locate the template under K]9"_UnN
* the Source Creation and Management node. Right-click the template and choose k4[|'Dk?
* Open. You can then make changes to the template in the Source Editor. d$Pab*
*/ 2FW\O0U
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package com.tot.count; `6xkf&Kt
import tot.db.DBUtils; lh;:M-b9
import java.sql.*; gjAIEI
/** ixT:)|'i
* )}?#
* @author A?pbWt~}
*/ g #6E|n
public class CountControl{ fk x \=
private static long lastExecuteTime=0;//上次更新时间 a,WICv0E
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 L');!/:
/** Creates a new instance of CountThread */ qCnZhJ
public CountControl() {} wGP;Vbk
public synchronized void executeUpdate(){ 6Z%U`,S
Connection conn=null; sU{NHC)5
PreparedStatement ps=null; vsl]92xI
try{ c>)Yt^q&K
conn = DBUtils.getConnection(); :FTMmW,>'
conn.setAutoCommit(false); D
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); AQ[GO6$,%H
for(int i=0;i<CountCache.list.size();i++){ ptZ <ow&
CountBean cb=(CountBean)CountCache.list.getFirst(); ?TKRjgW`@_
CountCache.list.removeFirst(); E`uY1B[c
ps.setInt(1, cb.getCountId()); SF<c0bR9
ps.executeUpdate();⑴ %Va!\#
//ps.addBatch();⑵ `.Qi?* ^
} &?yZv{
//int [] counts = ps.executeBatch();⑶ VQS~\:1
conn.commit(); FK5<6n,U
}catch(Exception e){ J\M>33zu
e.printStackTrace(); A*/HjTX
} finally{ O2%?
try{ :1bWVM)
if(ps!=null) { vz7J-CH
ps.clearParameters(); 5X:*/FuS@
ps.close(); ry` z(f
ps=null; T"DlT/\
} >)M`IU[d^.
}catch(SQLException e){} CyXRi}W.
DBUtils.closeConnection(conn); 428>BQA
} |='z{WS
} z-.+x3&o @
public long getLast(){ 1NgCw\
return lastExecuteTime; 9vvx*rD
} W)f/0QX}W
public void run(){ @3C>BLI8+
long now = System.currentTimeMillis(); =t H:,SH
if ((now - lastExecuteTime) > executeSep) { 5?F__Hx*2
//System.out.print("lastExecuteTime:"+lastExecuteTime); jGpN,/VQa
//System.out.print(" now:"+now+"\n"); Tw;3_Lj
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ([m
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lastExecuteTime=now; 9E>|=d|(d
executeUpdate(); xY^%&n
} 75/(??2
else{ f m)pulz
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'g
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} A"G
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} ^Uf]Q$uCjE
} sEGO2xeI
//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 .@@?Pj?)
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类写好了,下面是在JSP中如下调用。 L"4mL,
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<% ;E3>ay6m8
CountBean cb=new CountBean(); SfaQvstN
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $4 S@
CountCache.add(cb); [nrYpb4
out.print(CountCache.list.size()+"<br>"); dE4L=sTEsy
CountControl c=new CountControl(); sE Q=dcK
c.run(); 3 +G$-ru
out.print(CountCache.list.size()+"<br>"); bj>v|#r^
%>