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: ,Wtw0)4
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CountBean.java DVQr7tQf
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/* YB*)&@yx
* CountData.java 5{H)r
* GtRpgM
* Created on 2007年1月1日, 下午4:44 +:A `e+\
* \mF-L,yu
* To change this template, choose Tools | Options and locate the template under <XL%*
* the Source Creation and Management node. Right-click the template and choose 6 `6I<OJ\
* Open. You can then make changes to the template in the Source Editor. pbzt8 P[
*/ ;5X6`GlS#5
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package com.tot.count; }#zL)+XI
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/** pI@71~|R
* l6zAMyau5
* @author 9WHE4'Sa
*/ l4gH]!/@
public class CountBean { n'rq
private String countType; ?M90K)&g{
int countId; c((3 B
/** Creates a new instance of CountData */ (JU8F-/9
public CountBean() {} lU 9o"2
public void setCountType(String countTypes){
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this.countType=countTypes; 5a |[cR
} 4lo7yx
public void setCountId(int countIds){ 51:5rN(_
this.countId=countIds; #jbC@A9Pe
} x.t<@y~
public String getCountType(){ ;apLMMsWC
return countType; g.\b@0Uy'
} CXUF=IE
public int getCountId(){ R/u0,
return countId; [w](x
} 2<7pe@c98
} X8}r= K~
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CountCache.java c |%5SA
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/* S5|7D[*
* CountCache.java ImQ-kz?b
* 4#t'1tzu#
* Created on 2007年1月1日, 下午5:01 mI2Gs)SO
* |A4B4/!
* To change this template, choose Tools | Options and locate the template under t{,$?}
* the Source Creation and Management node. Right-click the template and choose I/'>MDB!
* Open. You can then make changes to the template in the Source Editor. !fs ~ >
*/ %g*nd#wG
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package com.tot.count; *wAX&+);
import java.util.*; E[hSL#0
/** do`'K3a"
* }51QUFhL0
* @author -raK
*/ \,v^v]|
public class CountCache { !,-'wT<v
public static LinkedList list=new LinkedList(); zGe =l;
/** Creates a new instance of CountCache */ fq1w <e
public CountCache() {} ^uX"04>;
public static void add(CountBean cb){ +4J'> dr
if(cb!=null){ xb7!!PR
list.add(cb); 8V(~u^!%_
} W'Gh:73'}
} '"Cqq{*
} =ZHN]PP
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CountControl.java @MQfeM-@
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/* q2k}bb +
* CountThread.java Z=hn}QY.(
* ZS l K
* Created on 2007年1月1日, 下午4:57 ~#EXb?#uS
* 0"-H34M<D
* To change this template, choose Tools | Options and locate the template under D _\HX9
* the Source Creation and Management node. Right-click the template and choose SdufI_'B
* Open. You can then make changes to the template in the Source Editor. 'bv(T2d~~
*/ &WCVdZK:
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package com.tot.count; 2!f'l'}
import tot.db.DBUtils; bil>;&h
import java.sql.*; 7ey|~u2
/** ( 3,7
* 2AqcabI9
* @author Jbima>
*/ m:EYOe,w
public class CountControl{ ")boY/ P/w
private static long lastExecuteTime=0;//上次更新时间 q89yW)XG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 a"+VP>4
/** Creates a new instance of CountThread */ ABEEJQ
public CountControl() {} 4&]NC2I
public synchronized void executeUpdate(){ GNG.N)q#C
Connection conn=null; : Q,O:
PreparedStatement ps=null; Z(E.F,k
try{ j%vxCs>
conn = DBUtils.getConnection(); HVC|0}
conn.setAutoCommit(false); :U1V 2f'l3
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); R^E-9S\@
for(int i=0;i<CountCache.list.size();i++){ WUDXx %
CountBean cb=(CountBean)CountCache.list.getFirst(); PC=s:`Y}R
CountCache.list.removeFirst(); PVKq&Q?
ps.setInt(1, cb.getCountId()); Kd#64NSi$A
ps.executeUpdate();⑴ PHsM)V+
//ps.addBatch();⑵ NFU=PS$
} G4F~V't
//int [] counts = ps.executeBatch();⑶ #.j:P#
conn.commit(); 9 Up>e
}catch(Exception e){ Rlr[uU_
e.printStackTrace(); Cn9MboXX
} finally{ ht:L
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try{ ,!~U5~
if(ps!=null) { 4[0.M
ps.clearParameters(); ' ]Km%uwL
ps.close(); 8W.-Y|[5?
ps=null; z ISy\uka
} ZDrTPnA[
}catch(SQLException e){} ^-}3+YA
DBUtils.closeConnection(conn); H]lD*3b
} a
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} oRn 5blj
public long getLast(){ gn 9CZ
return lastExecuteTime; Dx3Sf}G
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} R[lA@q:
public void run(){ @XF/hhGE_y
long now = System.currentTimeMillis(); _*(:6,8
if ((now - lastExecuteTime) > executeSep) { 4.&et()}
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7_7^&.Hh
//System.out.print(" now:"+now+"\n"); RML'C:1
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); atFu
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lastExecuteTime=now; FLlL0Gu
executeUpdate(); ^q~.5c|
} j%0g*YI
else{ RG_)<U/B
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 3TD!3p8
} l5k]voG
} 8j%lM/ v
} r,Pu-bhF
//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 _`94CC:
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类写好了,下面是在JSP中如下调用。 9;c]_zt
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<% h9{'w
CountBean cb=new CountBean(); `=foB-(zt
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |B*`%7{+
CountCache.add(cb); CV,[x[L#{
out.print(CountCache.list.size()+"<br>"); qoD
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CountControl c=new CountControl(); j[1^#kE
c.run(); u`X}AKC
out.print(CountCache.list.size()+"<br>"); U#_rcu
%>