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: 3G;#QK-c
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CountBean.java 8}^R jMgI
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/* e[:i`J2
* CountData.java DC-tBbQkk
* x e!([^l&
* Created on 2007年1月1日, 下午4:44 k|SywATr
* W{1"
* To change this template, choose Tools | Options and locate the template under bRhc8#kw)
* the Source Creation and Management node. Right-click the template and choose >p[skN
* Open. You can then make changes to the template in the Source Editor. 0[O ."9
*/ BKfkB[*F
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package com.tot.count; 3rUuRsXn
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/** gpe/ dfyJ9
* ]c=nkS
* @author z87_/(nu
*/ NQdz]o
public class CountBean { #3h~Z)+y
private String countType; q5UD!&W
int countId; .Z0$KQ'iy
/** Creates a new instance of CountData */ Z.iQm{bI
public CountBean() {} 6
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public void setCountType(String countTypes){ !/qQ:k-.
this.countType=countTypes; 'WC>
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} G)S(a4
public void setCountId(int countIds){ %^?yI
this.countId=countIds; ylo/]pVs
} !SxZN d v
public String getCountType(){ '20S oVp
return countType; .GM}3(1fX`
} A;'*>NS
public int getCountId(){ 9!kH:Az[p
return countId; VOY#Y*)g
} M`=bJO:
} l?rT_uO 4
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CountCache.java p#
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/* "+@>!U
* CountCache.java XoZw8cY
* D rMG{Yiu
* Created on 2007年1月1日, 下午5:01 l[cBDNlrC;
* ifYC&5}SI
* To change this template, choose Tools | Options and locate the template under rRK^vfoJ`
* the Source Creation and Management node. Right-click the template and choose 4P(ysTuM
* Open. You can then make changes to the template in the Source Editor. <8SRt-Cr
*/ DsI{*#
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package com.tot.count; bTrQ(qp
import java.util.*; IdzrQP
/** `O'@TrI
* M
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* @author UojHlTg#bT
*/ H)Kt!v8
public class CountCache { |K jy4.2
public static LinkedList list=new LinkedList(); ENEn Hu^
/** Creates a new instance of CountCache */ 0nDlqy6b1b
public CountCache() {} WL6p+sN'
public static void add(CountBean cb){ :AzP3~BI
if(cb!=null){ gEBwn2
list.add(cb); {Y p;R
} 7H=^~J
} tK$x=9M
} R[/]iK+!&
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CountControl.java 2S{IZ]
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/* j$f `:A
* CountThread.java G]T A7~VT
* FQ72VY
* Created on 2007年1月1日, 下午4:57 bN',-[E
* s)e' }y
* To change this template, choose Tools | Options and locate the template under ~5f|L(ODX
* the Source Creation and Management node. Right-click the template and choose 6kc/
* Open. You can then make changes to the template in the Source Editor. \qU .?V[2
*/ 3cp"UU}.
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package com.tot.count; }: W6Bo-|
import tot.db.DBUtils; 9kkYD
import java.sql.*; nKoc%TNqe
/** :<`hsKy&
* g@ ZZcBx
* @author lk5}bnd5
*/ vT7ei"~&u
public class CountControl{ HKr6h?Si^
private static long lastExecuteTime=0;//上次更新时间
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~TGk`cAM>
/** Creates a new instance of CountThread */ tvC7LL NP<
public CountControl() {} g!k'tizYD
public synchronized void executeUpdate(){ r}gp{Pf7e
Connection conn=null; <( 0TK5
PreparedStatement ps=null; ^<@9ph
try{ p:,(r{*?
conn = DBUtils.getConnection(); 9J$z/j;X
conn.setAutoCommit(false);
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); #hBDOXHPf
for(int i=0;i<CountCache.list.size();i++){ a*8^M\>m4
CountBean cb=(CountBean)CountCache.list.getFirst(); z]NN ^pIa
CountCache.list.removeFirst(); D;VFMP
ps.setInt(1, cb.getCountId()); LZ@4,Uj
ps.executeUpdate();⑴ @nJ#kd[
//ps.addBatch();⑵ FuYV}C
} {$<X\\&r
//int [] counts = ps.executeBatch();⑶ C?FUc cI
conn.commit(); d.7pc
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}catch(Exception e){ J%
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e.printStackTrace(); sQT0y(FW
} finally{ 0!n6tz lT
try{ !/w<F{cl
if(ps!=null) { <tEN1i
ps.clearParameters(); /CtR|~w L
ps.close(); |WiK*
ps=null; crJyk #_
} 3
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}catch(SQLException e){} W@^O'&3d
DBUtils.closeConnection(conn); Y%UfwbX!g
} N'fE^jqU
} r )cGee
public long getLast(){ +3
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return lastExecuteTime; ^G,]("di`
} xQ
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public void run(){ O)'Bx=S4Ke
long now = System.currentTimeMillis(); NU*6MT4
if ((now - lastExecuteTime) > executeSep) { `N~;X~XFk
//System.out.print("lastExecuteTime:"+lastExecuteTime); oEE*H2l\
//System.out.print(" now:"+now+"\n"); 1{oq8LB
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
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lastExecuteTime=now; i#t)tM"
executeUpdate(); Uk u~"OGC
} \c&%F=1+*
else{ P9/5M4]tt
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} Y~T;{&wi
} 'IweN
} C@` eYi
//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 Uhc2`r#q
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类写好了,下面是在JSP中如下调用。 igp[cFN
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<% I3QK~ V*j)
CountBean cb=new CountBean(); 6mJa
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); MfhJb_q`
CountCache.add(cb); Kb~s'cTxIO
out.print(CountCache.list.size()+"<br>"); !5Ko^: +Y
CountControl c=new CountControl(); LL+ROX^M
c.run(); [kx_Izi/T
out.print(CountCache.list.size()+"<br>"); nz:I\yA
%>