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: [L(hG a
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CountBean.java ig+4S[L~n
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/* +TJEG?o
* CountData.java igC_)C^i>
* c#cx>wq9
* Created on 2007年1月1日, 下午4:44 EWjgI_-
* KbW9s,:p
* To change this template, choose Tools | Options and locate the template under _[h8P9YI4
* the Source Creation and Management node. Right-click the template and choose Z(GfK0vU
* Open. You can then make changes to the template in the Source Editor. W|5_$p
*/ w$ fJ4+
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package com.tot.count; {38bv.3'
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/**
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* F]+~x/!
* @author j/!H$0PN
*/ <AoXEuD
public class CountBean {
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private String countType; #,NvO!j<4
int countId; mUoIJ3fv_,
/** Creates a new instance of CountData */ .uz|/Zy
public CountBean() {} vbG]mMJ
public void setCountType(String countTypes){ |j~lkzPnV
this.countType=countTypes; B.dT)@Lx0
} ('[TLHP
public void setCountId(int countIds){ vVxD!EL
this.countId=countIds; s1j{x&OSq
} g(E"4M@t!
public String getCountType(){ v|';!p|
return countType; ^Q}eatEn
} gl%`qf6:O
public int getCountId(){ B&?sF" Y
return countId; v6=-g$FG
} R[B?C;+(O
} EnVuD
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CountCache.java (5Nv8H8|
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/* 9 ;i\g=
* CountCache.java 2f~($}+*
* %;xOB^H^
* Created on 2007年1月1日, 下午5:01 ~@W*r5/
* p{$p
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* To change this template, choose Tools | Options and locate the template under F>hZ{
* the Source Creation and Management node. Right-click the template and choose +-?/e-z")
* Open. You can then make changes to the template in the Source Editor. yYZxLJ='
*/ x.mrCJn)
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package com.tot.count; w n|]{Ww35
import java.util.*; ""iaGH+Cxw
/** Vr.Y/3N&'
* zg)sd1@
* @author x2Lq=zwJ
*/ &HZmQ>!R D
public class CountCache { s%4M$e
public static LinkedList list=new LinkedList(); RW'nUL?_\
/** Creates a new instance of CountCache */ 07v!Zj
public CountCache() {} 5*g]qJF
public static void add(CountBean cb){ 9LC&6Q5O&
if(cb!=null){ i5}4(sV
list.add(cb); ),}AI/j;zY
} rVnd0K
} yR5XJ;Tct
} ne}+E
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CountControl.java Dh4
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/* iUk-'
* CountThread.java W i.5Y{
* t<iEj"5
* Created on 2007年1月1日, 下午4:57 )FN;+"IJ
* KJn!Ap
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose bpAv1udX-W
* Open. You can then make changes to the template in the Source Editor. nAJdr*`a,5
*/ V N{NA+I
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package com.tot.count; 1Tp/MV/>
import tot.db.DBUtils; K>:]Bx#F7
import java.sql.*; k;W@LfP
/** cf_|nL#9
* x3+oAb@o/
* @author I?#85l{>
*/ Hy:V`>
public class CountControl{ B5%n(,Lx
private static long lastExecuteTime=0;//上次更新时间 72uz<i!&$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 {V19Zv"j
/** Creates a new instance of CountThread */ q/9H..6
public CountControl() {} T=f|,sK +7
public synchronized void executeUpdate(){ Jb_1LZ)]
Connection conn=null; `O?T.p)
PreparedStatement ps=null; @&F@I3`{
try{ oTjyN\?H
conn = DBUtils.getConnection(); 2NGeC0=
conn.setAutoCommit(false); E_z;s3AXQ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); uQ$^;Pr
for(int i=0;i<CountCache.list.size();i++){ #65^w=Sp}
CountBean cb=(CountBean)CountCache.list.getFirst(); ?
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CountCache.list.removeFirst(); B_`y|sn
ps.setInt(1, cb.getCountId()); ~T7B$$
ps.executeUpdate();⑴ WUc#)EEM)
//ps.addBatch();⑵ NH<gU_s8{9
} ./vZe_o)j$
//int [] counts = ps.executeBatch();⑶ AFvgbn8Qh
conn.commit(); 4LcX<BU9
}catch(Exception e){ RprKm'b8x`
e.printStackTrace(); 2zSG&",2D
} finally{ ) /vhclkb
try{ 8F(h*e_?
if(ps!=null) { ZIR0PQh\
ps.clearParameters(); 1F8 W9b^D
ps.close(); -Y#sI3o*R8
ps=null; 8M,9kXq{L
} }TQ{`a@
}catch(SQLException e){} #eZ6)i<
DBUtils.closeConnection(conn); >Hb^P)3
} KOq;jH{$
} moj]j`P5a
public long getLast(){ n]_[NR) i
return lastExecuteTime; UV
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} 63|+2-E2Q
public void run(){ BcjP+$k4_
long now = System.currentTimeMillis(); ^mWybPqx
if ((now - lastExecuteTime) > executeSep) { d,vNem-Z*L
//System.out.print("lastExecuteTime:"+lastExecuteTime); h}_~y'^!
//System.out.print(" now:"+now+"\n"); ?<&O0'Q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); kqYa*| l
lastExecuteTime=now; c
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executeUpdate(); yq-=],h
} HW4.zw
else{ >Iewx
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,Y?sfp
} =\#%j|9N9
} {gA\ph%s
} LTV{{Z+
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 }eQRN<}P
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类写好了,下面是在JSP中如下调用。 W%2
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<% &c(WE
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CountBean cb=new CountBean(); /iNa'W5\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >SN|?|2U/
CountCache.add(cb); -4w=s|#.\
out.print(CountCache.list.size()+"<br>"); PjT=$]
CountControl c=new CountControl(); .roqEasu8
c.run(); H7Uli]e3
out.print(CountCache.list.size()+"<br>"); p^nL&yIW,%
%>