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: NeAkJG=<
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CountBean.java U&yXs'3a&
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/* <+o-{{E[
* CountData.java jl;_lcO
* rL3<r
* Created on 2007年1月1日, 下午4:44 mEfI2P)#|
* ;,[6 n|M
* To change this template, choose Tools | Options and locate the template under z6ISJb
* the Source Creation and Management node. Right-click the template and choose DZ92;m
* Open. You can then make changes to the template in the Source Editor. k"&loh
*/ 'DO^ ($N
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package com.tot.count; 5XySF #
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/** Ig}G"GR
* lT#&\JQ
* @author k"\%x=#
*/ T$T:~8tK3
public class CountBean { Aayh'xQ
private String countType; gKeqf-UWKJ
int countId; g6{.C7m
/** Creates a new instance of CountData */ .<`i!Ls
public CountBean() {} ig<Eyr
public void setCountType(String countTypes){ [zl@7X1{_
this.countType=countTypes; _8P"/(
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} ) DXN|<A
public void setCountId(int countIds){ 0]4kR8R3[
this.countId=countIds; %tul(Z~<1
} [Oen{c9A
public String getCountType(){ 0B fqEAl
return countType; o(w!x!["
} k4fc5P
public int getCountId(){ .)
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return countId; B4 yU}v
} |z\5Ik!fF]
} |x@)%QeC
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CountCache.java NAjY,)>'K
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/* 4)0 %^\p
* CountCache.java QEKSbxL\W
* [zv>Wlf,%
* Created on 2007年1月1日, 下午5:01 !l|vO(
* 2_ M+akqy^
* To change this template, choose Tools | Options and locate the template under 4
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* the Source Creation and Management node. Right-click the template and choose TP o%zZo
* Open. You can then make changes to the template in the Source Editor. z%$ E6Im
*/ oFM\L^Y?$$
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package com.tot.count; J!5BH2bg
import java.util.*; _Z?{&k
/** @)PA9P |
* 6(awO2{BP
* @author N`XJA-DE
*/ D,q=?~
public class CountCache { g?`g+:nug
public static LinkedList list=new LinkedList(); t\~lGG-p
/** Creates a new instance of CountCache */ i)9}+M5
public CountCache() {} ;, P-2\V/
public static void add(CountBean cb){ QR4rQu
if(cb!=null){ &7z79#1NS
list.add(cb); :W]?6=
} aEU[k>&
} e9e%8hL
} KiW4>@tY
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CountControl.java ASmMj;>UM
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/* ~f=~tN)hZ
* CountThread.java jJFWPD]u
* hoY.2 B _
* Created on 2007年1月1日, 下午4:57 ah<1&UG,
*
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* To change this template, choose Tools | Options and locate the template under T'\B17
:*
* the Source Creation and Management node. Right-click the template and choose !OWPwBm;
* Open. You can then make changes to the template in the Source Editor. xw_VK1
*/
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package com.tot.count; 3ThBy'
import tot.db.DBUtils; 06DT2
import java.sql.*; S<}2y 9F
/** ].F7.
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* @_"B0$,-i
* @author :#D?b.=
*/ Vp8t8X1`
public class CountControl{ s2f95<B
private static long lastExecuteTime=0;//上次更新时间 J)1:jieQ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~^d. zIN!
/** Creates a new instance of CountThread */ r/v'h@
public CountControl() {} <;O=h;
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public synchronized void executeUpdate(){ ]=\Mf<
Connection conn=null; P^m+SAAB
PreparedStatement ps=null; z'@j9vT
try{ [Du@go1C
conn = DBUtils.getConnection(); GT\,
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conn.setAutoCommit(false); 3t<XbHF9
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); U'^AJ2L8
for(int i=0;i<CountCache.list.size();i++){ +5J "G/f
CountBean cb=(CountBean)CountCache.list.getFirst(); [h>|6%sW
CountCache.list.removeFirst(); <$\vL
ps.setInt(1, cb.getCountId()); LhM{LUi
ps.executeUpdate();⑴ l`lo5:w
//ps.addBatch();⑵ KrOoxrDcp
} dw
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//int [] counts = ps.executeBatch();⑶ !iKR~&UpAL
conn.commit(); m-f"EFmP
}catch(Exception e){ A
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e.printStackTrace(); GwiG..Y]&
} finally{ G| 7\[!R
try{ a<X8l^Ln
if(ps!=null) { blxAy
ps.clearParameters(); .G[y^w)w}
ps.close(); IV{,'+hT
ps=null; [NcS[*qp
} `5 py6,
}catch(SQLException e){} (;u tiupW
DBUtils.closeConnection(conn); d,=Kv
} ""Ul6hRgv
} ?pgdj|"a
public long getLast(){ w:Ui_-4*>
return lastExecuteTime; CU=}]Y
} P.*J'q 28
public void run(){ <>aBmJs4
long now = System.currentTimeMillis(); "|W .o=R
if ((now - lastExecuteTime) > executeSep) { )6|7L)Dk
//System.out.print("lastExecuteTime:"+lastExecuteTime); `(A6uakd
//System.out.print(" now:"+now+"\n"); =PHl|^
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); X!5N2x
lastExecuteTime=now; $ tf;\R
executeUpdate(); W-wy<<~f
} {Z[yY6Nu
else{ xsK{nM6g
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); TJ(P TB;
} _'&N0 1
} Oq"(oNG@
} j0J}d _
//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 ~82[pY
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类写好了,下面是在JSP中如下调用。 2mL1BG=Yk
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<% 8Ml&lfn_8
CountBean cb=new CountBean(); 'Z2:u!E
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Dd|}LV
CountCache.add(cb); g-'y_'%0G
out.print(CountCache.list.size()+"<br>"); zx^]3}
CountControl c=new CountControl(); h}xUZ:
c.run(); &d`T~fl|
out.print(CountCache.list.size()+"<br>"); 0
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