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: .RpWE.C
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CountBean.java y]}N[l
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/* scPvuHzl
* CountData.java =kb/4eRg
* ^+}~"nvD
* Created on 2007年1月1日, 下午4:44 y3ST0=>j}
* +J3Y}A4W3X
* To change this template, choose Tools | Options and locate the template under xTy)qN]P
* the Source Creation and Management node. Right-click the template and choose H^XTzE
* Open. You can then make changes to the template in the Source Editor. lz4M)pL^
*/ ^L-; S
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package com.tot.count; ]Cp`qayct
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/** q>m[vvt"
* A\v]ZN4
* @author >NZJ-:t
*/ MPMAFs
public class CountBean { >2mV{i&
private String countType; 7)*QX,4C
int countId; ^TT_BAI
/** Creates a new instance of CountData */ Hlz$@[$
public CountBean() {} $$eBr8
public void setCountType(String countTypes){ 0}q*s!
this.countType=countTypes; kyL]4:@W`
} %JuT'7VB
public void setCountId(int countIds){ XhmUtbs
this.countId=countIds; lL*"N|Y
} CK8!7=>}^
public String getCountType(){ MS& 'Nj
return countType; k<
} ZL'krV
public int getCountId(){ ~N8$abQJV
return countId; yK0iW
} ycrM8Mu
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} Hu"TEhW(2
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CountCache.java c"pu"t@/Z
beFD}`
/* k;
ned
* CountCache.java sfs2ki H
* a7"Aq:IjU
* Created on 2007年1月1日, 下午5:01 {Z#=ppvs
* < mp_[-c
* To change this template, choose Tools | Options and locate the template under ;+rcT;_^/
* the Source Creation and Management node. Right-click the template and choose m:c .dei5
* Open. You can then make changes to the template in the Source Editor. Ly]J-BTe
*/ 7Jn%c<s
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package com.tot.count; rVB\\
import java.util.*; a&<_M$J&
/** 7,FhKTV1/
* MGH2z:
* @author xo#K_"E
*/ wpcqgc
public class CountCache { 9S8V`aC
public static LinkedList list=new LinkedList(); R,m|+[sl
/** Creates a new instance of CountCache */ VTK +aI
public CountCache() {} $8>II0C.
public static void add(CountBean cb){ i)7B :uA
if(cb!=null){ 7|(o=+Bt
list.add(cb); d bHxc@H
} Uac.8wQh
} ))E| SAr
} v>sjS3
fiW2m=h_
CountControl.java w6|l ~.$=
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/* 'LC0hoV
* CountThread.java !nTI(--
* \ `|
* Created on 2007年1月1日, 下午4:57 g:Ry.=F7W
* rtz ]PH
* To change this template, choose Tools | Options and locate the template under -AwkP
* the Source Creation and Management node. Right-click the template and choose \Yr&vX/[p
* Open. You can then make changes to the template in the Source Editor. :]9CdkaU
*/ r)oR`\7
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package com.tot.count; r}-vOPn`E
import tot.db.DBUtils; A}_0iwG
import java.sql.*; synueg
/** ;OSEMgB1
* C#P7@ JE
* @author t""d^a#Dp
*/ [@/s! i @
public class CountControl{ yHn8t]{
private static long lastExecuteTime=0;//上次更新时间 5W(`lgVs,
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 petq6)g?
/** Creates a new instance of CountThread */ lfqsoIn;
public CountControl() {} $'COsiK7
public synchronized void executeUpdate(){ 9b)'vr*Hy7
Connection conn=null; {0L)B{|
PreparedStatement ps=null; gQuU_dbXSB
try{ Vn?|\3KY
conn = DBUtils.getConnection(); cpM]APF-
conn.setAutoCommit(false); '}E"Mdb
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Pa"[&{ :
for(int i=0;i<CountCache.list.size();i++){ ;$FMOMR
CountBean cb=(CountBean)CountCache.list.getFirst(); (>`S{L
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CountCache.list.removeFirst(); 8$38>cGY^
ps.setInt(1, cb.getCountId()); X)S4vqf}
ps.executeUpdate();⑴ :b<<
//ps.addBatch();⑵ 6o~g3{Ow
} [9\Mf4lh#
//int [] counts = ps.executeBatch();⑶ }UqL2KXi4
conn.commit(); ja^
}catch(Exception e){ 8r48+_y3u
e.printStackTrace();
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} finally{ Aq_?8 Cd
try{ )zu m.6pT
if(ps!=null) { +HoCG;C{
ps.clearParameters(); p?sFX$S
ps.close(); *ch7z|wo.
ps=null; wPaMYxO/
} 8^hbS%s!
}catch(SQLException e){} 'S6JpWG1
DBUtils.closeConnection(conn); #ib?6=sPC
} h&x;#.SYK
} +d=8 /3O%
public long getLast(){ a~F\2`Q
return lastExecuteTime; K'b #}N\
} Z%QU5.
public void run(){ OD).kP}s^
long now = System.currentTimeMillis(); FH7l6b,^
if ((now - lastExecuteTime) > executeSep) { o=
&/;X
//System.out.print("lastExecuteTime:"+lastExecuteTime); `9nk{!X\
//System.out.print(" now:"+now+"\n"); ef:YYt{|q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `\Te,
lastExecuteTime=now; \8/$ZEom
executeUpdate(); ||'A9
} eV(
else{ 7$7#z\VWu
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); #=czqZw
} jB3Rue:+g
} "T~A*a^
} "2hs=^&8
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Y
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类写好了,下面是在JSP中如下调用。 #F ;@Qi3z
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<% lj@ibA]
CountBean cb=new CountBean(); uw{K&Hxw
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); M`,`2I A
CountCache.add(cb); u9G
out.print(CountCache.list.size()+"<br>"); h8:5[;e
CountControl c=new CountControl(); ? ;$f"Wl
c.run(); )CG,Udu
out.print(CountCache.list.size()+"<br>"); lnt}l
%>