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: 74VN3m
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CountBean.java /"A)}>a
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/* :DP%>H|
* CountData.java B3V:? #
* <qD/ #$
* Created on 2007年1月1日, 下午4:44 ]I9Hbw
* ~]HeoQK
* To change this template, choose Tools | Options and locate the template under z4f\0uQ
* the Source Creation and Management node. Right-click the template and choose AtRu)v6r
* Open. You can then make changes to the template in the Source Editor. v\Zni4
*/ d\aarhD8*
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package com.tot.count; ^dB~#A1
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/** wB6ILTu1
* ViV"+b#gu
* @author }."3&u't
*/ fsU6o4
public class CountBean { G%
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private String countType; 7XKPC+)1ya
int countId; Vv=/{31
/** Creates a new instance of CountData */ AV0m31b
public CountBean() {} nQuiRTU<
public void setCountType(String countTypes){ b #U
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this.countType=countTypes; vn"2"hPF|
} SFrQPdX6V
public void setCountId(int countIds){ E#t;G:+A
this.countId=countIds;
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} `UFRv
public String getCountType(){ *vn^
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return countType; 7cx~?xk <m
} kTG4h@w
public int getCountId(){ 6X(Yv2X&4%
return countId; 1JIL6w_
} ("{JNA/
} zk8 o[4
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CountCache.java ^6!C":f
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/* NG-Wn+W@b
* CountCache.java fY@Y$S`Fh
* `}:q@:%
* Created on 2007年1月1日, 下午5:01 Jx;"@
* o:ki IZ]
* To change this template, choose Tools | Options and locate the template under ~F8M_
* the Source Creation and Management node. Right-click the template and choose `IQ01FuP
* Open. You can then make changes to the template in the Source Editor. -"qw5Y_oF?
*/
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package com.tot.count; mA|&K8H
import java.util.*; y:Xs/RS
/** L/1zG/@
* l2uh"!
* @author wjk-$p
*/ sS 5 ]d8
public class CountCache { Rk2V[R.`S
public static LinkedList list=new LinkedList(); |FZ)5
/** Creates a new instance of CountCache */ 74YMFI
public CountCache() {} =a>a A Z
public static void add(CountBean cb){ QjH;'OVt
if(cb!=null){ 'N$hbl
list.add(cb); o -tc}Aa
} ^UP!y!&N
} ,L#Qy>MOb
} [Nb0&:$ay
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CountControl.java '>[l1<d!G
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/* ]H8CVue
* CountThread.java UpL1C~&
* Qs2E>C
* Created on 2007年1月1日, 下午4:57 yidUtSv=,
* FQdz":5
* To change this template, choose Tools | Options and locate the template under 7%?2>t3~
* the Source Creation and Management node. Right-click the template and choose 7'wt/9
* Open. You can then make changes to the template in the Source Editor. ~=h M y`Ml
*/ CJ B
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package com.tot.count; [+0rlmB
import tot.db.DBUtils; Va^Y3/
import java.sql.*; Z;kRQ
/** )1Rn;(j9Re
* QC7Ceeh]4
* @author xU$A/!oK
*/ Wbo{v r[2+
public class CountControl{ ySP1,xq
private static long lastExecuteTime=0;//上次更新时间 L/Cp\|~ O
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g_lj/u]P
/** Creates a new instance of CountThread */ "?Dov/+Q.
public CountControl() {} .kpL?_
public synchronized void executeUpdate(){ l` 9<mL
Connection conn=null; SS?^-BI
PreparedStatement ps=null; &phers
try{ /BB(riG
conn = DBUtils.getConnection(); ^VsX9
conn.setAutoCommit(false); ~!( (?8"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 4;anoqiG\
for(int i=0;i<CountCache.list.size();i++){ f,:SI&c\
CountBean cb=(CountBean)CountCache.list.getFirst(); D<}z7W-
CountCache.list.removeFirst(); >hqev-
ps.setInt(1, cb.getCountId()); noY~fq/U
ps.executeUpdate();⑴ }{>)2S
//ps.addBatch();⑵ j8p</gd
} nn>1OO
//int [] counts = ps.executeBatch();⑶ ""cnZZ5)
conn.commit(); 4yhan/zA
}catch(Exception e){ ^LfN6{
e.printStackTrace(); H/8H`9S$
} finally{ 4]L5%=atn
try{ N@D]Q&;+(T
if(ps!=null) { 8S2sNpLi-g
ps.clearParameters(); *`~
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ps.close(); dQUZ11
ps=null; X0<qG
} IS *-MLi
}catch(SQLException e){} b~;gj^
DBUtils.closeConnection(conn); \)Sa!XLfT
} F?!P7 zW
} yWI30hW
public long getLast(){ !u@XEN>/
return lastExecuteTime; GT$.#};u
} H;('h#=cD
public void run(){ kev|AU (WX
long now = System.currentTimeMillis(); 6H+'ezM
if ((now - lastExecuteTime) > executeSep) { Rf *we+
//System.out.print("lastExecuteTime:"+lastExecuteTime); y V=Ku
//System.out.print(" now:"+now+"\n"); p=F!)TnJN
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); yo\R[i(
lastExecuteTime=now; 7!%/vO0m
executeUpdate(); E'3=qTbiD
} *v1M^grKd
else{ 2aQR#lcv
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); yW::`
} j8k5B"
} >b2j j+8
} Jg3OMUt
//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 FT.6^)-
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类写好了,下面是在JSP中如下调用。 }^|g|xl!
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<% s"u6po.'
CountBean cb=new CountBean(); [
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); y $,K^f
CountCache.add(cb); = MQpYX
out.print(CountCache.list.size()+"<br>"); 0ws1S(pq
CountControl c=new CountControl(); kKbq?}W[
c.run(); Z>=IP-,>
out.print(CountCache.list.size()+"<br>"); 1'.SHY|
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