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: zD^*->`p
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CountBean.java {:;6 *W
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/* <cm(QNdcC
* CountData.java GY`mF1b
* /tdRUX
* Created on 2007年1月1日, 下午4:44 (}B3df
* E)>.2{]C>
* To change this template, choose Tools | Options and locate the template under okm
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* the Source Creation and Management node. Right-click the template and choose L0\~K~q
* Open. You can then make changes to the template in the Source Editor. Hnft1
*/ VEsIhjQ
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package com.tot.count; 8yCt(ms
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/** MoZ8A6e?B
* QJ\+u
* @author Z1}@N/>>
*/ G22{',#r8
public class CountBean { 56JxHQu
private String countType; 8&Md=ZvK`
int countId; t1`.M$
/** Creates a new instance of CountData */ jWL%*dJrN
public CountBean() {} JIc(hRf9>
public void setCountType(String countTypes){ O,PTY^
this.countType=countTypes; w%1-_;.aU6
} z{H=;"+rh
public void setCountId(int countIds){ gCV+amP
this.countId=countIds; +lplQh@RB
} sEymwpm9
public String getCountType(){ c/lT S
return countType; T{So2@_&
} yQcIfl]f
public int getCountId(){ #fx>{ vzH
return countId; 0fJz[;dV>n
} &K*Kr=9N
} \/s0p
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CountCache.java g@zhhBtQ
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/* J
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* CountCache.java tdsfCvF=a
* ?zuKVi?I
* Created on 2007年1月1日, 下午5:01 H-,p.$3}
* y[{}124
* To change this template, choose Tools | Options and locate the template under ~2;\)/E\
* the Source Creation and Management node. Right-click the template and choose Na>w~
* Open. You can then make changes to the template in the Source Editor. !aB~G}'
*/ B ({g|}|G+
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package com.tot.count; 5<XWbGW
import java.util.*; vw6>eT
/** kBU`Q{.
* S2jn pf}
* @author BgT(~8'
*/ dsU'UG7L
public class CountCache { Q{|_"sfJ
public static LinkedList list=new LinkedList(); `mthzc3W
/** Creates a new instance of CountCache */ <v6W
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public CountCache() {} $[g#P^
public static void add(CountBean cb){ Te%V+l
if(cb!=null){ k4PXH
list.add(cb); _lDNYpv
} |%oI,d=ycv
} :6:,s#av
} d#HlO}
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CountControl.java R`J.vMT
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/* GG`j9"t4
* CountThread.java _+j#.o>
* iA<'i8$P
* Created on 2007年1月1日, 下午4:57 R=<%!
* 4,08`5{
* To change this template, choose Tools | Options and locate the template under =9h!K:,k
* the Source Creation and Management node. Right-click the template and choose 6 w'))Z
* Open. You can then make changes to the template in the Source Editor. T/FZn{I
*/ T>pyYF1Q
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package com.tot.count; ;X;(7
import tot.db.DBUtils; @\r2%M-
import java.sql.*; ~.>8ww
/** 9k~%HN-[
* w^9< I]
* @author E{P94Phv
*/ G8zbb
public class CountControl{ 7p-
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private static long lastExecuteTime=0;//上次更新时间 -'F27])
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 xI_0`@do
/** Creates a new instance of CountThread */ .D;6
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public CountControl() {} Ob{Tn@
public synchronized void executeUpdate(){ GYg.B<Q.
Connection conn=null; ({zWyl
PreparedStatement ps=null; UxxX8N
try{ cm0$v8
conn = DBUtils.getConnection(); =W&m{F96
conn.setAutoCommit(false); CpB,L
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); YG /@=Z.
for(int i=0;i<CountCache.list.size();i++){ n.i8?:
CountBean cb=(CountBean)CountCache.list.getFirst(); .SLpgYFL{
CountCache.list.removeFirst(); (xE |T f
ps.setInt(1, cb.getCountId()); /M JI^\CA
ps.executeUpdate();⑴ qyAnq%B}
//ps.addBatch();⑵ l-P6B9e|\
} 5KfrkZ
//int [] counts = ps.executeBatch();⑶ N/'8W9#6
conn.commit(); G3 |x%/Fbp
}catch(Exception e){ ,!, tU7-H
e.printStackTrace(); `kE7PXqa
} finally{ M.xZU\'ty
try{ D2GF4%|
if(ps!=null) { } '?qUy3x
ps.clearParameters(); _%er,Ed
ps.close(); S dN&%(ZE
ps=null; L[Ot$
} @q`T#vd
}catch(SQLException e){} 5dhy80|g]
DBUtils.closeConnection(conn); 6i%6u=um3
} ,
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} U{j4FlB
public long getLast(){ D.-G!0!
return lastExecuteTime; >28l9U
} "h #/b}/
public void run(){ ?"^{:~\N
long now = System.currentTimeMillis(); A*vuS Qt(
if ((now - lastExecuteTime) > executeSep) { B`t/21J
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9^9-\DG
//System.out.print(" now:"+now+"\n"); ?68~ g<d,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); icX4n
lastExecuteTime=now; MV??S{^4
executeUpdate(); ~o/k?l
} SQhVdYU1'
else{ Faa>bc~E
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {6WG
} q7<d|s
} OR*JWW[]
} C/QmtT~`e
//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 t|V<K^
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类写好了,下面是在JSP中如下调用。 :8]8[
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CountBean cb=new CountBean(); / Y od
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 6VC|]
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CountCache.add(cb); a5R.
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out.print(CountCache.list.size()+"<br>"); MPDRMGR@i
CountControl c=new CountControl(); h_{f_GQ"
c.run(); l
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out.print(CountCache.list.size()+"<br>"); L"/?[B":
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