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: 1tr>D:c\
2?r8>#_*
CountBean.java kCwTv:)
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/* :te xl
* CountData.java 6m.Ku13;
* Zn/9BO5
* Created on 2007年1月1日, 下午4:44 z1FbW&V
* Qr<%rU^{.
* To change this template, choose Tools | Options and locate the template under I|j tpv}
* the Source Creation and Management node. Right-click the template and choose n% `r
* Open. You can then make changes to the template in the Source Editor. (O-)uC
*/ ~c="<xBE
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package com.tot.count; .3U[@ *b(
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/** %'t~e?d!
* XF7W'^
* @author :HE]P)wz-
*/ `;_tt_
public class CountBean { t@u\ 4bv
private String countType; cV{ZDq
int countId; y{{EC#
/** Creates a new instance of CountData */ n>E*g|a
public CountBean() {} eb/V}%
public void setCountType(String countTypes){ fD~!t 8J
this.countType=countTypes; @1@q6@9Tu
} 0`P]fL+&
public void setCountId(int countIds){ a`-hLX)~Z
this.countId=countIds; ];I| _fXo%
} &V?q d{39
public String getCountType(){ Ij#a
return countType; >Y/[zfI2
} y\_S11{v
public int getCountId(){ S[a5k;8GL
return countId; O|>1~^w
} da2[
} ILi5WuOYX
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CountCache.java w}.'Tebu
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/* I:e2sE
":
* CountCache.java f)zg&Ib
* ?:?4rIZ<
* Created on 2007年1月1日, 下午5:01 @"I#b99
* ;ULC|7rL
* To change this template, choose Tools | Options and locate the template under }91mQ`3
* the Source Creation and Management node. Right-click the template and choose H< ;Fb;b
* Open. You can then make changes to the template in the Source Editor. *!'&:
*/ f^)uK+:.
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package com.tot.count; O&,O:b:@
import java.util.*; xploFw~
/** 9 <KtI7
* O$Vm#|$sq
* @author Su"_1~/2S
*/ lkfFAwnc
public class CountCache { k,7+=.6
public static LinkedList list=new LinkedList(); <!9fJFE
/** Creates a new instance of CountCache */ \ZFQ?e,d
public CountCache() {} s3-ktZ@
public static void add(CountBean cb){ >fye^Tx
if(cb!=null){ }iSakq'
list.add(cb); |"yf@^kdC
} z9ShP&^4[
} 8sIrG
} JQ_gM._3
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CountControl.java CjQ"o Qw
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/* v1C.\fL
* CountThread.java nr>{ uTa
* @LKG\zYBu
* Created on 2007年1月1日, 下午4:57 H\I!J@6g
* <8)s
* To change this template, choose Tools | Options and locate the template under RW7oL:$dt
* the Source Creation and Management node. Right-click the template and choose c[ony:6
* Open. You can then make changes to the template in the Source Editor. "F"_G
*/ EyPJvs
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package com.tot.count; tin|,jA =
import tot.db.DBUtils; b#g
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import java.sql.*; P!y`$Ky&
/** >C3NtGvy
* atf%7}2
* @author A$~xG(
*/ =u8D!AxT
public class CountControl{ $W$# CTM
private static long lastExecuteTime=0;//上次更新时间 ZB[(Tv1
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 T@|l@xm~L
/** Creates a new instance of CountThread */ +oy&OKCa
public CountControl() {} |WAD $3
public synchronized void executeUpdate(){ V+qJrZ,i
Connection conn=null; g6g$nY@Jm
PreparedStatement ps=null; lmQ 6X
try{ #jZ@l3
conn = DBUtils.getConnection(); 5ttMua <G?
conn.setAutoCommit(false); KO|pJ3
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); k=7Gr;;l=p
for(int i=0;i<CountCache.list.size();i++){ C,r`I/;
CountBean cb=(CountBean)CountCache.list.getFirst(); /u)Rppu
CountCache.list.removeFirst(); :B=8_M
ps.setInt(1, cb.getCountId()); R|1xXDLm*E
ps.executeUpdate();⑴ 0HR|aqPo
//ps.addBatch();⑵ ^5]uBOv
} gKN}Of@^1
//int [] counts = ps.executeBatch();⑶ iS"8X#[]N
conn.commit(); XY{:tR_al
}catch(Exception e){ Vd+Q:L
e.printStackTrace(); <'[Ku;m
} finally{ d;~ 3P
try{ =dM.7$6) R
if(ps!=null) { voV:H[RD9
ps.clearParameters(); -+}5ma
ps.close(); jJVT_8J
ps=null; &$c5~9p\B
} 7':f_]
}catch(SQLException e){} h}|6VJ@.
DBUtils.closeConnection(conn); |qlS6Aln
} 8lOI\-
} e8WEz
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public long getLast(){ kT^*>=1
return lastExecuteTime; )4ilCS&
} nlzW.OLM
public void run(){ ALd]1a&
long now = System.currentTimeMillis(); \2Og>{"U
if ((now - lastExecuteTime) > executeSep) { Xlv#=@;O]
//System.out.print("lastExecuteTime:"+lastExecuteTime); -\kXH"%
//System.out.print(" now:"+now+"\n"); e40udLH~x
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); @Y
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lastExecuteTime=now; $J"%I$%X=
executeUpdate(); EqnpMHF
} {pDTy7!Hs
else{ 'Y!pY]Z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); A XBkJ'jd
} hOPe^e"
} hCM8/Vvx6
} CE#\Roi x)
//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 cJ(BiL-uF
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类写好了,下面是在JSP中如下调用。 )nwZ/&@
H&X:!xa5
<% AJyq>0p
CountBean cb=new CountBean(); F>dwL bnb
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :N@U[Wx0A
CountCache.add(cb); %bP~wl~
out.print(CountCache.list.size()+"<br>"); MZ|\S/
CountControl c=new CountControl(); Yb[n{.%/g
c.run(); d/{Q
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out.print(CountCache.list.size()+"<br>"); \=!H 2M
%>