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: C,Q>OkSc
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CountBean.java <43O,Kx'Su
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/* v8W .84e-
* CountData.java @
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* [KMW*pA7
* Created on 2007年1月1日, 下午4:44 *,q ?mO
* C;];4[XR
* To change this template, choose Tools | Options and locate the template under d5T M_C
* the Source Creation and Management node. Right-click the template and choose b1JXC=*@
* Open. You can then make changes to the template in the Source Editor. p;zV4uSv
*/ 0eUK'
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package com.tot.count; eG*<=.E
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/** q}p&<k
* yaza
* @author A-x; ai]
*/ $OB 2ZS"
public class CountBean { 1`J-|eH=Q
private String countType; XFKe6:
int countId; 3cfW|J
/** Creates a new instance of CountData */ w=H
public CountBean() {} GcaLP*%>B
public void setCountType(String countTypes){ 35;|r
this.countType=countTypes; }7&.FV"
} W{:^P0l
public void setCountId(int countIds){ 89o&KF]
this.countId=countIds; i#]}k
} PKFjM~J
public String getCountType(){ Evu`e=LaG
return countType; ,|6O}E&
} FFX-kS
public int getCountId(){ 0=O(+
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return countId; U27YH1OK
} + 2v6fan
} "`HkAW4GZa
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CountCache.java 2-=Ov@y2k!
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/* 3kfrOf.4h
* CountCache.java S"hA@j
* IlN: NS
* Created on 2007年1月1日, 下午5:01 xe?!UCUb@
* /2z, ?,jL
* To change this template, choose Tools | Options and locate the template under c
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* the Source Creation and Management node. Right-click the template and choose Io_bS+
* Open. You can then make changes to the template in the Source Editor. `R[cM; c2
*/ 1%Hc/N-
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package com.tot.count; h; " 9.
import java.util.*; 3
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/** s1
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* F(h
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* @author EPeKg{w
*/ rnAQwm-8O%
public class CountCache { 7slpj8
public static LinkedList list=new LinkedList(); g{ ()
/** Creates a new instance of CountCache */ }jE[vVlRw
public CountCache() {} 7:/gO~gI
public static void add(CountBean cb){ ;Aqj$ x
if(cb!=null){ tKS'#y!R
list.add(cb); a4d7;~tZ
} _:+hB9n s
} vJ,r}$H3
} c'|](vOd]
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CountControl.java ^(F@ #zN}
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/* >U\1*F,Om,
* CountThread.java .9NYa |+0
* 8
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* Created on 2007年1月1日, 下午4:57 wn-1fz<d
* &9Kni/
* To change this template, choose Tools | Options and locate the template under -UB XWl
* the Source Creation and Management node. Right-click the template and choose ;cEoc(<?
* Open. You can then make changes to the template in the Source Editor. G!T_X*^q2U
*/ ,>p1:pga
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package com.tot.count; !i>d04u`%
import tot.db.DBUtils; LWdA3%
import java.sql.*; -DuI
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/** 'fjouO
* [s{ B vn
* @author <N{wFvF
*/ XCyU)[wY
public class CountControl{ vSnGPLl
private static long lastExecuteTime=0;//上次更新时间 (S~kNbIa
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 r03%+:
/** Creates a new instance of CountThread */ @}\i`H1s
public CountControl() {} <k?pnBI_
public synchronized void executeUpdate(){ AqiH1LAE
Connection conn=null; d{J@A;da
PreparedStatement ps=null; KAJR.YNm
try{ p'`?CJq8
conn = DBUtils.getConnection(); riZ :#I
conn.setAutoCommit(false); 9OYyR
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); S6g_$Q7
for(int i=0;i<CountCache.list.size();i++){ eDsB.^|l
CountBean cb=(CountBean)CountCache.list.getFirst(); S]&:R)#@
CountCache.list.removeFirst(); B*(BsXQLY
ps.setInt(1, cb.getCountId()); IeZ9 "o h
ps.executeUpdate();⑴ n)0M1o#
//ps.addBatch();⑵ |}? H$d
} D 0Mxl?S?
//int [] counts = ps.executeBatch();⑶ ~&aULY?)]
conn.commit(); k Nvb>v
}catch(Exception e){ [D+,I1u2h
e.printStackTrace(); z/]]u.UP
} finally{ g< xE}[gF
try{ -2[#1S*
if(ps!=null) { ]$uC~b
ps.clearParameters(); C
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ps.close(); riL|B3
ps=null; &) 64:l&
} 0l3[?YtXc
}catch(SQLException e){} tI@aRF=p]2
DBUtils.closeConnection(conn); A=0{}B#
} #M||t|9iu?
} J'ZC5Xr
public long getLast(){ #UE}JR3g
return lastExecuteTime; 'ieTt_1.G
} !Rc
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public void run(){ jEE!H/
long now = System.currentTimeMillis(); 8_E(.]U
if ((now - lastExecuteTime) > executeSep) { b}DC|?~M
//System.out.print("lastExecuteTime:"+lastExecuteTime); -u(,*9]cJ*
//System.out.print(" now:"+now+"\n"); zYP6m3n
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }SC&6B?G
lastExecuteTime=now; `KtP;nG
executeUpdate(); )Q62 I\
} n"`V|
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else{ Qd~z<U l
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); gs3c1Qa3b
} 3"zPG~fY{
} EjFn\|VK
} c9G%;U)
//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 H[nco#
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类写好了,下面是在JSP中如下调用。 @dk-+YxG
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<% I-/>M/66
CountBean cb=new CountBean(); er5!ne
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 4D2U,Ds
CountCache.add(cb); \i/HHP[%
out.print(CountCache.list.size()+"<br>"); <{k`K[)
CountControl c=new CountControl(); EcL6lNTR+
c.run(); yuy\T(7BN
out.print(CountCache.list.size()+"<br>"); :'B(DzUR
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