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: q1{H~VSn"
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CountBean.java zGlZ!t:
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/* 9S7A!AKE
* CountData.java kxB.,'
* zJN7<sv
* Created on 2007年1月1日, 下午4:44 K|r Lkl9
* >SmV74[s2
* To change this template, choose Tools | Options and locate the template under 2N [=
* the Source Creation and Management node. Right-click the template and choose #f,y&\Xmf
* Open. You can then make changes to the template in the Source Editor. ~$,qgf
*/ dA~
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package com.tot.count; ^+|De}`u
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/** L"(4R^]
* hpbf&S4
* @author a[!%Ld
*/ 7<\C?`q"
public class CountBean { A*yi"{FLi
private String countType; zw@'vncc
int countId; mEAXM1J|
/** Creates a new instance of CountData */ qSU|=
public CountBean() {} :l u5Uu~
public void setCountType(String countTypes){ [:EvTY
this.countType=countTypes; Sm{>rR
} ef"?|sn
public void setCountId(int countIds){ %VNlXHO.
this.countId=countIds; 6dqsFns}e
} %
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public String getCountType(){ G;iEo4\?
return countType; 2tQ`/!m>v$
} Z}6^ve
public int getCountId(){ umEVy*hc
return countId; $7Jo8^RE
} 1OaXo!
} 4_?7&G0(
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CountCache.java AONDx3[
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/* 7 A$B{
* CountCache.java j Ch=@<9
* :;]Oc
* Created on 2007年1月1日, 下午5:01 ?)4?V\$
* $14:(<
* To change this template, choose Tools | Options and locate the template under W6c]-pc
* the Source Creation and Management node. Right-click the template and choose ?9+@+q
* Open. You can then make changes to the template in the Source Editor. ^C)n$L>C0
*/ "f.Z}AbP
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package com.tot.count; }WLh8i?_
import java.util.*; 256LH Y|6
/** 7*+]wEs
* xl9aV\W
* @author &]6)LFm
*/ \K2*Q&>
public class CountCache { 6 ,ANNj
public static LinkedList list=new LinkedList(); qQ[b VD\*
/** Creates a new instance of CountCache */ xb2?lL]
public CountCache() {} R[tC^]ai
public static void add(CountBean cb){ 7j<e)"
if(cb!=null){ X@N$Z{
list.add(cb); DbI!l`Vn4
} ;U=q-tb
} JtKp(k&
} ;i uQ?MR3
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CountControl.java ,U,By~s
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/* =JLh?Wx
* CountThread.java gO?44^hMe
* !v|ISyK
* Created on 2007年1月1日, 下午4:57 X?r48l??
* >c8GW
>\N
* To change this template, choose Tools | Options and locate the template under [4Ll0GSp
* the Source Creation and Management node. Right-click the template and choose <Q< AwP
* Open. You can then make changes to the template in the Source Editor. #U7_a{cn"M
*/ BcWcdr+}9
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package com.tot.count; <Cpp?DW_
import tot.db.DBUtils; ~!iQ6N?PY
import java.sql.*; `NRH9l>B7
/** <~emx'F|
*
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* @author J:dof:q
*/ U
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public class CountControl{ AnsjmR:Jv
private static long lastExecuteTime=0;//上次更新时间 |f( ~@Q:
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 9v)%dO.
/** Creates a new instance of CountThread */ 8;P2A\X
public CountControl() {} A?!I/|E^;
public synchronized void executeUpdate(){ q z&+=d@
Connection conn=null; r{Rg920
PreparedStatement ps=null; K/_9f'^
try{ cR{>IH 4^
conn = DBUtils.getConnection(); l3o#@sz:
conn.setAutoCommit(false); LE^G&<!
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); FyL_xu\e
for(int i=0;i<CountCache.list.size();i++){ SkNre$>t{
CountBean cb=(CountBean)CountCache.list.getFirst(); _W!p8cB
CountCache.list.removeFirst(); 5`[n8mU
ps.setInt(1, cb.getCountId()); X&m'.PA
ps.executeUpdate();⑴ yBed kj
//ps.addBatch();⑵ E:E4ulak
} ,8G{]X)
//int [] counts = ps.executeBatch();⑶ 5r{;CKKz
conn.commit(); vEe NW
}catch(Exception e){ er.L7
e.printStackTrace(); :c[n\)U[aa
} finally{ {U!St@
try{ WP**a Bp
if(ps!=null) { j5$BK[p.
ps.clearParameters(); S]3Ev#>
ps.close(); 9Mm!%Hu
ps=null; qk(P>q8[
} `BFIC7a
}catch(SQLException e){} AN:@fZ
DBUtils.closeConnection(conn); 6&U+6gb
} =ziwxIo6
} +?D6T!)
public long getLast(){ hv$yV%.`
return lastExecuteTime; 'BMy8
} qAkx<u
public void run(){ %i0?UpA
long now = System.currentTimeMillis(); @R~5-m
if ((now - lastExecuteTime) > executeSep) { VzS&`d.h
//System.out.print("lastExecuteTime:"+lastExecuteTime); )
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//System.out.print(" now:"+now+"\n"); DrW#v-d
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6$ Q,Y}j
lastExecuteTime=now; }1 vT)
executeUpdate(); donw(_=
} CR<`ZNuWz
else{ %!Q`e79g8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); (LAXM
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} {1J&xoV"
} ?|;yVew
} d?,M/$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 ]Al;l*yw
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类写好了,下面是在JSP中如下调用。 IputF<p
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<% 72oWhX=M%
CountBean cb=new CountBean(); JHn*->m
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )4Q?aMm
CountCache.add(cb); 5__+_hO
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out.print(CountCache.list.size()+"<br>"); |Yi)"-
CountControl c=new CountControl(); Fr?z"
c.run(); J<j&;:IRd
out.print(CountCache.list.size()+"<br>"); 4_M>OD/"
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