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: g|_-O"l
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CountBean.java \A'MEd-
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/* xFcJyjo^z
* CountData.java S;[g0j
* i_8q!CL@{
* Created on 2007年1月1日, 下午4:44 8*yhx
* %|md0
* To change this template, choose Tools | Options and locate the template under .} <$2.
* the Source Creation and Management node. Right-click the template and choose </0@7
* Open. You can then make changes to the template in the Source Editor. !IlsKMZ
*/ a!YpSFr
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package com.tot.count; *ZP$dQ
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/** '&4W@lvyz
* I\J^@&JE
* @author ;~Y0H9`
*/ P wL]v. :
public class CountBean { d>@&[C!28
private String countType; @MMk=/WDw
int countId; DEEQ/B{
/** Creates a new instance of CountData */ p<IMWe'tP
public CountBean() {} 7,U^v}$
public void setCountType(String countTypes){ ?:F#WDD
this.countType=countTypes; Iqe=)
} U6V+jD}L]
public void setCountId(int countIds){ ``bIqY
this.countId=countIds; #`R`!4
} )=6|G^
public String getCountType(){ $OMTk
return countType; k fS44NV
} 0 =#)-n
public int getCountId(){ /Zs;dam
return countId; 1s5FjD?M
} lJHV c"*/
} WO{V,<;
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CountCache.java Cisv**9
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/* 6}bUX_!&s
* CountCache.java b
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* P)bS ;w\(Y
* Created on 2007年1月1日, 下午5:01 f4Aevh:
* 63R?=u@
* To change this template, choose Tools | Options and locate the template under OrN>4S
* the Source Creation and Management node. Right-click the template and choose (}1 gO
* Open. You can then make changes to the template in the Source Editor. .9X, )^D
*/ &c<0g`x
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package com.tot.count; KICy!
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import java.util.*; aq/'2U 7
/** oGz-lO{lt
* b?Dhhf
* @author =?fxPT[1K
*/
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public class CountCache { QR4!r@*=
public static LinkedList list=new LinkedList(); o'nju.'
/** Creates a new instance of CountCache */ Y]
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public CountCache() {} B?d^JWTZ
public static void add(CountBean cb){ R:49Gn:F
if(cb!=null){ HmxA2 ~C
list.add(cb); ;{@ [ek6
} HPM
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} y"4Nw]kU
} ;Y<Hi\2oy
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CountControl.java YCJc Dab
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/* s~OGlPK
* CountThread.java uA]Z"
* yk
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* Created on 2007年1月1日, 下午4:57 1&\ A#
* Fy(-.S1
* To change this template, choose Tools | Options and locate the template under iU3GUsPy
* the Source Creation and Management node. Right-click the template and choose GF(<!PC
* Open. You can then make changes to the template in the Source Editor. @lvvI<U
*/ I9JiH,+
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package com.tot.count; ?"oW1a\
import tot.db.DBUtils; ;2lKo ="
import java.sql.*; f0UB?
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/** mI5BJ
* QU0FeGtz
* @author ]&l.-0jt
*/ J=QuZwt
public class CountControl{ 2M`]nAk2a
private static long lastExecuteTime=0;//上次更新时间 ?LE\pk
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %6-5hBzZN
/** Creates a new instance of CountThread */ b5r.N1ms
public CountControl() {} %"#%/>U4
public synchronized void executeUpdate(){ v X=zqV
Connection conn=null; 6:Eu[PE~w
PreparedStatement ps=null; VRr_s:CWK
try{ .9r+LA{
conn = DBUtils.getConnection(); Skm$:`u;
conn.setAutoCommit(false); H oA[UT
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); rof&O
for(int i=0;i<CountCache.list.size();i++){ >kK!/#ZA
CountBean cb=(CountBean)CountCache.list.getFirst(); Co`O{|NS}!
CountCache.list.removeFirst(); IB~`Ht8
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ps.setInt(1, cb.getCountId()); uL`6}0
ps.executeUpdate();⑴ Cso!VdCX
//ps.addBatch();⑵ s{IXth6
} (;1rM}B;1
//int [] counts = ps.executeBatch();⑶ `U-i{i
conn.commit(); 3aMfZa<=
}catch(Exception e){ j+B+>r^
e.printStackTrace(); g.3 .
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} finally{ xc|pl!ns
try{ qIm?F>>@
if(ps!=null) { (?luV#{5
ps.clearParameters(); vAeh#V~#
ps.close(); wD(1Sr5n
ps=null; <Uz~V;
} *Ru@F:
}catch(SQLException e){} IP)?dnwG
DBUtils.closeConnection(conn); ^;on
} rgth2y]
} Iud]*5W
public long getLast(){ )TYrb:M'm
return lastExecuteTime; ^Rgm3?7
} "S#}iYp
public void run(){ R~9\mi5^UH
long now = System.currentTimeMillis(); :` FL95
if ((now - lastExecuteTime) > executeSep) { iF.eBL%
//System.out.print("lastExecuteTime:"+lastExecuteTime); /]0-|Kg+R
//System.out.print(" now:"+now+"\n"); #.
mc+n:I
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [(%6]L}
lastExecuteTime=now; >FrF"u:kM
executeUpdate(); +f#oij
} p#-;u1-B
else{ h>s|MZQ:*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 41\r7
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} j/I^\Ms
} *hJ&7w ~
} #X~{p4Lr
//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 Kk?]z7s-4
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类写好了,下面是在JSP中如下调用。 xR9<I:^&
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<% ^F5Q(A
CountBean cb=new CountBean(); #Y)Gos
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Z^Y_+)=s
CountCache.add(cb); /CpU.^V
out.print(CountCache.list.size()+"<br>"); DA>_9o/l
CountControl c=new CountControl(); L;wfTZa
c.run(); SZGeF;N
out.print(CountCache.list.size()+"<br>"); ;.%Ii
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%>