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: FKox0Jmh=
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CountBean.java 4Oy.,MDQP
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/* *IWFeu7y
* CountData.java 6~ 7 ;o_>
* 3e%l8@R@
* Created on 2007年1月1日, 下午4:44 -XVEV
* U|J$?aFDr
* To change this template, choose Tools | Options and locate the template under LZr0]g{Pu/
* the Source Creation and Management node. Right-click the template and choose hza> jR
* Open. You can then make changes to the template in the Source Editor. 5L-lpT8P
*/ Q1`<fD
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package com.tot.count; Q(|PZng
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/** =.36y9Mfo
* !/Iq{2LX
* @author Z5G]p4
*/ YlswSQ
public class CountBean { Zc'|!pT _
private String countType; -)1-~7
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int countId; GilQtd3\
/** Creates a new instance of CountData */ )jyq{Jb
public CountBean() {} ~+O `9&
public void setCountType(String countTypes){ :}y9$p
this.countType=countTypes; d/D,P=j"
} _wf5%(~b
public void setCountId(int countIds){ D]IBB>F
this.countId=countIds; Fe!D%p Qv
} Bo`Tl1K#
public String getCountType(){ d<Ggw#}:m
return countType; q0,kDM66
} Q6"uK
public int getCountId(){ U|gpCy
return countId; G'
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} =p<?Hu
} x_*%*H
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CountCache.java *YWk1Cwjo
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/* 9O;cJ)tXY
* CountCache.java ^Ye\u1n4
* UMV)wy|j
* Created on 2007年1月1日, 下午5:01 .%=V">R
* /;?M?o"H
* To change this template, choose Tools | Options and locate the template under :Sr?6FPc
* the Source Creation and Management node. Right-click the template and choose .it#`Yz;
* Open. You can then make changes to the template in the Source Editor. [J^
*/ /<);=&[
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package com.tot.count; R}8XRe
import java.util.*; AS)UJ/lC
/** lbQQtpEKO
* :ygWNK[6D
* @author "(v%1tGk
*/ r9#
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public class CountCache { OS-sk!
public static LinkedList list=new LinkedList(); 0Vkl`DmeM.
/** Creates a new instance of CountCache */ Z$p0&~
public CountCache() {} V
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public static void add(CountBean cb){ +oI3I~
if(cb!=null){ T .REq4<
list.add(cb); glj7$
} w~z[wm Okp
} =pcF:D#+
} [}OgSP9i
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CountControl.java 5;\gJf
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/* -'`TL$
* CountThread.java mMSh2B
* &$'z
* Created on 2007年1月1日, 下午4:57 oRM)%N#
* +uo{ m~_4
* To change this template, choose Tools | Options and locate the template under J NVr
* the Source Creation and Management node. Right-click the template and choose &;E5[jO^D
* Open. You can then make changes to the template in the Source Editor. -#In;~
*/ YAVy9$N-
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package com.tot.count; %'
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import tot.db.DBUtils; ujFzJdp3k
import java.sql.*; s&a1y~rv
/** Aw5pd7qKL
* oR .cSGh
* @author b| M3`
*/ \25/$Ae}c
public class CountControl{ cc}Key@D
private static long lastExecuteTime=0;//上次更新时间 7a4o1;l
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 &Lm-()wb
/** Creates a new instance of CountThread */ 7y^%7U \
public CountControl() {} +JRF0T
public synchronized void executeUpdate(){ +k\Uf*wh
Connection conn=null; yNg9X(U
PreparedStatement ps=null; G(iJi
try{ q[3x2sR
conn = DBUtils.getConnection(); <eN_1NTH_
conn.setAutoCommit(false); 'sh~,+g
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); o:S0*
for(int i=0;i<CountCache.list.size();i++){ C NsNZJ
CountBean cb=(CountBean)CountCache.list.getFirst(); dq\FBwfe
CountCache.list.removeFirst(); 6at1bQ$
ps.setInt(1, cb.getCountId()); bWWXc[O2&(
ps.executeUpdate();⑴ vb
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//ps.addBatch();⑵ 6e,xDr
} =<}<Ny
//int [] counts = ps.executeBatch();⑶ K+*Q@R D
conn.commit(); 6$U]9D
}catch(Exception e){ m)v''`9LU
e.printStackTrace(); {q%Sx*k9[
} finally{ #KxbM-1=
try{ #[{3} %b
if(ps!=null) { r]@0eb
ps.clearParameters(); B* kcNlW
ps.close(); xu5ia|gYz7
ps=null; dU) ]:>Uz
} VKp*9%9
}catch(SQLException e){} pM;vH]|
DBUtils.closeConnection(conn); &H}r%%|A
} d^03"t0O]
} Vj<:GRNQ,d
public long getLast(){ uvDzKMw~R
return lastExecuteTime; ?eH&'m}-
} YHNR3
public void run(){ ;~fT,7qBah
long now = System.currentTimeMillis(); k.<]4iS
if ((now - lastExecuteTime) > executeSep) { q<y#pL=k"*
//System.out.print("lastExecuteTime:"+lastExecuteTime); dzLQI}89+k
//System.out.print(" now:"+now+"\n"); 9.'h^#C
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); x:-.+C%
lastExecuteTime=now; qm/Q65>E
executeUpdate(); _Zk{!
} -;f*VM.a
else{ *eI)Z=8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ;!:U((wv
} T134ZXqqz
} mxor1P#|
} Lg8nj< TF
//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 ^`un'5Vk
#/PA A
类写好了,下面是在JSP中如下调用。 U*90m~)
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<% HhO".GA
CountBean cb=new CountBean(); B8E'ddUw
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); (c0A.L)
CountCache.add(cb); h(WrL
out.print(CountCache.list.size()+"<br>"); r0p w_j
CountControl c=new CountControl(); [MuEoWrq(}
c.run(); hW{j\@R
out.print(CountCache.list.size()+"<br>"); U(~+o
%>