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: yCt,-mz!z
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CountBean.java k_$9cVA
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/* miCW(mbO8
* CountData.java )4@La&
* |4lrVYG^K
* Created on 2007年1月1日, 下午4:44 V <;vy&&
* H)u<$y!8
* To change this template, choose Tools | Options and locate the template under Frxim
* the Source Creation and Management node. Right-click the template and choose h0v4!`PQ-
* Open. You can then make changes to the template in the Source Editor. XC NM
*/ ]z{f)`;I
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package com.tot.count; IC[iCrB
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/** h9J%NH
* Ny
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* @author F9Y/Z5 Ea
*/ SA1|7
public class CountBean { pl.D
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private String countType; cI
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int countId; q)Uh_l.Cj
/** Creates a new instance of CountData */ [`'[)B
public CountBean() {} L4w KG&
public void setCountType(String countTypes){ %?`TyVt&0
this.countType=countTypes; `tZ-8f
} _t+.I9kQ
public void setCountId(int countIds){ h4\j=Np
this.countId=countIds; O
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} =5PNH 2
public String getCountType(){ f-M 9OI
return countType; D. _*p
} iCK p"(kf
public int getCountId(){ >AsrPU[
return countId; 9~FB^3Nz_
} ,m^@S
} e,0y+~
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CountCache.java FSp57W$
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/* m:{ws~
* CountCache.java TAl#V7PF}
* *;]j#0
* Created on 2007年1月1日, 下午5:01 pjI<
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* Fo0dz
* To change this template, choose Tools | Options and locate the template under /6$8djw
* the Source Creation and Management node. Right-click the template and choose `!t+sX-n
* Open. You can then make changes to the template in the Source Editor. = @UgCu>=
*/ N8s2v W
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package com.tot.count; No1*~EQ
import java.util.*; MK*WStY
/** ^71!.b%
* /1Q
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* @author 4kZ9]5#.
*/ X 9lh@`3
public class CountCache { f T&>L
public static LinkedList list=new LinkedList(); RkW)B^#
/** Creates a new instance of CountCache */ %#^)hX,+Q
public CountCache() {} p%_m!
public static void add(CountBean cb){ Ul41RNy)
if(cb!=null){ c,\!<4
list.add(cb); HalkNR-eEm
} ?[|T"bE5[
} #t^y$9^
} <Fc @T4Q,
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CountControl.java ^JKV~+ Q
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/* JDIQpO"Qji
* CountThread.java cc"L> XoK
* w,'"2^Cwy
* Created on 2007年1月1日, 下午4:57 "gR W91
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* 3*DwXH +
* To change this template, choose Tools | Options and locate the template under BV9%|
* the Source Creation and Management node. Right-click the template and choose f8m%T%]f
* Open. You can then make changes to the template in the Source Editor. `(RQh@H
*/ RH=Tu6i
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package com.tot.count; c|s*(WljY
import tot.db.DBUtils; ?4]#gCks
import java.sql.*; x9c/;Q&m
/** :Y{aa1
* D~< 3
* @author N0D)d
*/ <}^W9>u<
public class CountControl{ C#y[UM5\k;
private static long lastExecuteTime=0;//上次更新时间 ikSm;.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 E903T' 's
/** Creates a new instance of CountThread */ S @EkrC\4n
public CountControl() {} .>K):|Opv
public synchronized void executeUpdate(){ P[.BK
Connection conn=null; v0ngM)^q
PreparedStatement ps=null; b0~AN#Es
try{ _-vf<QO]
conn = DBUtils.getConnection(); /p=9"?
conn.setAutoCommit(false); !+E|{Zj
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~}c`r 4
for(int i=0;i<CountCache.list.size();i++){ 2(,
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CountBean cb=(CountBean)CountCache.list.getFirst(); E%f;Z7G
CountCache.list.removeFirst(); rY
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ps.setInt(1, cb.getCountId()); ; U)a)l'y
ps.executeUpdate();⑴ 1lxsj{>U
//ps.addBatch();⑵ tPT\uD#t
} GQNs :oRJ'
//int [] counts = ps.executeBatch();⑶ ^Ms)T3dM
conn.commit(); m]1=o7
}catch(Exception e){ S<hj6A
e.printStackTrace(); rb/m;8v>
} finally{ 0]F'k8yLN
try{ C3Hq&TVf/
if(ps!=null) { :?Xd&u0){
ps.clearParameters(); 5 W<\J
ps.close(); x<0-'EF/S
ps=null; 3lyk/',
} N}Ol`@@#h
}catch(SQLException e){} JY\8^}'9
DBUtils.closeConnection(conn); P(_wT:8C?
} FN#6pM']|
} x4PH-f-7
public long getLast(){ n\nC.|_G@
return lastExecuteTime; "%c\i-&t
}
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public void run(){ I[~EQ{Iz
long now = System.currentTimeMillis(); 6AZJ,Q\E@
if ((now - lastExecuteTime) > executeSep) { ]7QRelMiz+
//System.out.print("lastExecuteTime:"+lastExecuteTime); B%v2)+?@
//System.out.print(" now:"+now+"\n"); X(-e-:B4;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Y *
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lastExecuteTime=now; kAbkhZ1^
executeUpdate(); z2m%L0
} %SRUHx[D
else{ 1PMBo=SUe8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); d9zI
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} >uok\sX
} @#T*OH
} ~~?4w.k
//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 k)W8%=R
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类写好了,下面是在JSP中如下调用。
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<% 8{5Y%InL
CountBean cb=new CountBean(); Hev S}L
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); &%~2Wm
CountCache.add(cb); {iP^51fy
out.print(CountCache.list.size()+"<br>"); |~mi6 lJ6
CountControl c=new CountControl(); M DnT
c.run(); ZQT14. $L
out.print(CountCache.list.size()+"<br>"); m6aq_u{W
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