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: M}>q>
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CountBean.java %M`&}'6'
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/* !8$}]uWP
* CountData.java moGbBkO
* {)M4h?.2
* Created on 2007年1月1日, 下午4:44 }`(kX] ][
* =|V3cM4'
* To change this template, choose Tools | Options and locate the template under ~Y(M>u.+!
* the Source Creation and Management node. Right-click the template and choose @?U5t1O<
* Open. You can then make changes to the template in the Source Editor. @tA.^k0`
*/ =[,adB
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package com.tot.count; VO9<:R
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/** !Zrvko
* a5iMCmL+
* @author SV~xNzo~
*/ y-U(`{[nM
public class CountBean { ,rKN/{M!
private String countType; DuWP)#kg
int countId; M\%{!Wzo8
/** Creates a new instance of CountData */ ocMf}"
public CountBean() {} ,#A,+!4
public void setCountType(String countTypes){ >h9U~#G=
this.countType=countTypes; tv0xfAV
} g 0L 4
public void setCountId(int countIds){ O]>Or3oO
this.countId=countIds; km^AX:r1
} z(ajR*\#
public String getCountType(){ khR3[ju {^
return countType; I'gnw~
} MG6Tk(3S
public int getCountId(){ \yqiv"'
return countId; |lv4X}H
} >@X=E3
} cA*%K[9
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CountCache.java E*%{Nn
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/* !\m.&lk'^
* CountCache.java d09GD[5
* dx~Wm1
* Created on 2007年1月1日, 下午5:01 Kk,->q<1
* 9T]]T Ev4
* To change this template, choose Tools | Options and locate the template under +0OQ"2^&
* the Source Creation and Management node. Right-click the template and choose {`'b+0[;@
* Open. You can then make changes to the template in the Source Editor. 5q<kt{06\
*/ rk~/^(!
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package com.tot.count; }XUHP%
import java.util.*; ?:ZH%R_`a
/** u32<=Q[
* zb<+x(0y"
* @author &$=F$
*/ WM#!X!Vo
public class CountCache { AIeYy-f
public static LinkedList list=new LinkedList(); 0C7"*H0R
/** Creates a new instance of CountCache */ bhI8b/
public CountCache() {} S$#Awen"@
public static void add(CountBean cb){ ;#+#W+0
if(cb!=null){ [kXe)dMX8
list.add(cb); = FE,G*
} $$4% .J26Z
}
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} X>CYKRtb
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CountControl.java 5u&jNU5m_
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/* u,C-U!A
* CountThread.java b&ADj8cKC
* bIH2cJ
* Created on 2007年1月1日, 下午4:57 1{wy%|H\
* 5xiYCOy
* To change this template, choose Tools | Options and locate the template under y`N1I
* the Source Creation and Management node. Right-click the template and choose Z`
Aiw."|
* Open. You can then make changes to the template in the Source Editor. (*EN! -/
*/ Ii9vA ^53
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package com.tot.count; #8`G&S*
import tot.db.DBUtils; R'F|z{8
import java.sql.*; cr!I"kTgD
/** QEVjXJOt0
* R =jK3yfw
* @author AkF1Hj
*/ )KNFS,5
public class CountControl{ !xlVyt5e
private static long lastExecuteTime=0;//上次更新时间 $OJ*Kul
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 o%dtf5}(,
/** Creates a new instance of CountThread */ >ko;CQR
public CountControl() {} /i]Gg
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public synchronized void executeUpdate(){ eI[z%j[Y*
Connection conn=null; NZ_45/(dx
PreparedStatement ps=null; 4M:oa#gh@
try{ a}fW3+>
conn = DBUtils.getConnection(); <sTaXaq?
conn.setAutoCommit(false); T4UY%E!0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Y}Ov`ZM!r
for(int i=0;i<CountCache.list.size();i++){ &8 (2U-
CountBean cb=(CountBean)CountCache.list.getFirst(); N5s_o0K4TU
CountCache.list.removeFirst(); G6
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ps.setInt(1, cb.getCountId()); _E~uuFMn*R
ps.executeUpdate();⑴ OS!47Z /q
//ps.addBatch();⑵ ]/a?:24 [
} ^cY5!W.q8
//int [] counts = ps.executeBatch();⑶ DJ\lvT#j
conn.commit(); ~(^[TuJC
}catch(Exception e){ HiWZ?G
e.printStackTrace(); cx$Oh`-Car
} finally{ vb%\q sf
try{ tpVtbh1)u
if(ps!=null) { .-r
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ps.clearParameters(); }vL[N~5\
ps.close(); =gj]R
ps=null; c{E-4PYbah
} 4Qw!YI#40$
}catch(SQLException e){} Jn&(v"_
DBUtils.closeConnection(conn); |k^X!C 0
} ^!}lA9\gY
} Ug9o/I@}C
public long getLast(){ &K7g8x"x.
return lastExecuteTime; Lt*H|9
} *Vc}W
public void run(){ j/W#=\xz
long now = System.currentTimeMillis(); f(3#5288
if ((now - lastExecuteTime) > executeSep) { 2Zl65
//System.out.print("lastExecuteTime:"+lastExecuteTime); !~RD>N&n
//System.out.print(" now:"+now+"\n"); wU=(_S,c
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); J3$ihH.
lastExecuteTime=now; OLiYjYd
executeUpdate(); ;[|x5o/<
} gcz1*3)
else{ j;'NJ~NZ$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~v5tx
} gh~C.>W}q+
} lr|-_snx2
} F'"-4YV>&
//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 bkY7]'.bz&
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类写好了,下面是在JSP中如下调用。 ?=\h/C
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<% Ar\`OhR
CountBean cb=new CountBean(); #3qkG)
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); IX3r$}4
CountCache.add(cb); gU8'7H2
out.print(CountCache.list.size()+"<br>"); ^EB}e15"
CountControl c=new CountControl(); 5tf/VT
c.run(); m7eO T
out.print(CountCache.list.size()+"<br>"); DZ EA*E >
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