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: |[}YM%e
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CountBean.java `UMv#-Y8
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/* 9`i=kp
* CountData.java s<H0ka@
* RtGETiA\b
* Created on 2007年1月1日, 下午4:44 'N)&;ADx-G
* cfMj^*I
* To change this template, choose Tools | Options and locate the template under uI@:\Rss
* the Source Creation and Management node. Right-click the template and choose FEw51a+V
* Open. You can then make changes to the template in the Source Editor. 5Jd&3pO
*/ SJ^.#^)
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package com.tot.count; [Pi8gj*
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/** uJA8PfbD
* }k.-xaj
* @author LpeQx\
*/ &OK(6o2m;
public class CountBean { sbZ)z#Tr
private String countType; k'&BAC.K,
int countId; ` QXO+'j4
/** Creates a new instance of CountData */ t8\F7F P
public CountBean() {} )\l}i%L:
public void setCountType(String countTypes){ YwQxN"
this.countType=countTypes; Cy4@\X%W
} Dr$k6kZ}'U
public void setCountId(int countIds){ uDay||7^g
this.countId=countIds; t@QaxZIlt;
} X,:^})]
public String getCountType(){ @bOhnd#W
return countType; EA|*|o4)
} %RG kXOgp
public int getCountId(){ IkFrzw p
return countId; W~aVwO'(
} lPSyFb"
} /jaTH_Q),:
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CountCache.java .C$S
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/* ZZ?0%9
* CountCache.java tq H7M0Ry
* __teh>MC
* Created on 2007年1月1日, 下午5:01 P {i\x#
* M' e<\wqm
* To change this template, choose Tools | Options and locate the template under m.pB]yq&
* the Source Creation and Management node. Right-click the template and choose jB!p,fqcb
* Open. You can then make changes to the template in the Source Editor. I;<0v@
*/ zUXQl{
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package com.tot.count; So{/V%
import java.util.*; N9tH0
/** x2=Bu#Y
* M(KsLu1
* @author , 7KP
*/ F&%@p&
public class CountCache { $wg5q\Rv
public static LinkedList list=new LinkedList(); de1cl<
/** Creates a new instance of CountCache */ rn $a)^!
public CountCache() {} y<0zAsT
public static void add(CountBean cb){ QMLz
if(cb!=null){ 6=U81
list.add(cb); Q^prHn*@
} T\I}s"d
} 3)88B"E
} g>-pC a
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CountControl.java #%O|P&rA
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/* dv-L!C
* CountThread.java Y[)b".K
* e+6mbJ7y
* Created on 2007年1月1日, 下午4:57 pFgpAxl
* "BT*9N=|
* To change this template, choose Tools | Options and locate the template under _HF66)X7
* the Source Creation and Management node. Right-click the template and choose ,%"!8T
* Open. You can then make changes to the template in the Source Editor. h?R{5?RxK
*/ J!Er%QUR
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package com.tot.count; 94VtGg=b}
import tot.db.DBUtils; V[ju7\>$Z
import java.sql.*; 86Hg?!<i.
/** .a2b&}/.d
* (
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* @author :B{Wf 2<z
*/ uonCD8
public class CountControl{ #(swVo:+E
private static long lastExecuteTime=0;//上次更新时间 ]8q#@%v}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 [ )3rc}:1
/** Creates a new instance of CountThread */ */c4b:s
public CountControl() {} eyW8?:
public synchronized void executeUpdate(){ -]el_:H
Connection conn=null; E|{(O
PreparedStatement ps=null; %"-bG'Yc
try{ S&/,+x'c|
conn = DBUtils.getConnection(); \ vn!SO7
conn.setAutoCommit(false); 9gq+,g>E_
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); GWFF.Mo^
for(int i=0;i<CountCache.list.size();i++){ 5~D(jHY;
CountBean cb=(CountBean)CountCache.list.getFirst(); 4`yE'%6.}
CountCache.list.removeFirst(); SU,G0.
ps.setInt(1, cb.getCountId()); Z$?(~ln
ps.executeUpdate();⑴ '41'Gn
//ps.addBatch();⑵ .3
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} |w5m2Z
//int [] counts = ps.executeBatch();⑶ S[ch/
conn.commit(); L~oy|K67
}catch(Exception e){ "<Ozoo1&w
e.printStackTrace(); L4O.= *P1
} finally{ fGZ56eH:
try{ &Va="HNKt
if(ps!=null) { E{;F4wT_@
ps.clearParameters(); v[;R(pt?
ps.close(); )
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ps=null; e"oTlB
} IiU\}<O
}catch(SQLException e){} EfX\" y
DBUtils.closeConnection(conn); e!W U
} "C0?s7Y
} wZ4w`|'
public long getLast(){ WwsH7X)
return lastExecuteTime; >|X )
} Q":,oZ2
public void run(){ /< k&[
long now = System.currentTimeMillis(); X)e#=w!fi3
if ((now - lastExecuteTime) > executeSep) { O22Q
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//System.out.print("lastExecuteTime:"+lastExecuteTime); e,kxg^
//System.out.print(" now:"+now+"\n"); ZnKjU ]m
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); r7)qr%n
lastExecuteTime=now; s\+|
ql
executeUpdate(); k5M5bH',
} IOA2/WQu
else{ xU/7}='T
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); |kY}G3/
} M*!WXQlud
} xXf,j#`"
} .n n&K}h
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 gY'-C
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类写好了,下面是在JSP中如下调用。 +m9ouF
}!Y=SP1e
<% N5[^W`Qf
CountBean cb=new CountBean(); HQvJ*U4++
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); pMHF u/|Pr
CountCache.add(cb); z$gtGrU
out.print(CountCache.list.size()+"<br>"); 3
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CountControl c=new CountControl(); 8`<e\g7-
c.run(); >.M>,m\
out.print(CountCache.list.size()+"<br>"); y2W|,=Vd
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