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: B[xR-6phW
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CountBean.java "jZm0U$,*
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/* C;sgK
* CountData.java hswTn`f
* <FmBa4ONU
* Created on 2007年1月1日, 下午4:44 XS0V:<+,
* {~GR8
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* To change this template, choose Tools | Options and locate the template under GFR!n1Hv
* the Source Creation and Management node. Right-click the template and choose u;n(+8sz
* Open. You can then make changes to the template in the Source Editor. 1| xN%27>
*/ |ft:|/^F&
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package com.tot.count; /=
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/** _IYY08&(r
* t>U!Zal"
* @author gEKO128
*/ X7e/:._SAH
public class CountBean { sA_X<>vAKJ
private String countType;
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int countId; z
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/** Creates a new instance of CountData */ )bYez
public CountBean() {} H%Y%fQ~^
public void setCountType(String countTypes){ 5L&:_iQZy
this.countType=countTypes; IH3FK!>6
} <-|SIF
public void setCountId(int countIds){ BQ#jwu0e
this.countId=countIds; <"I?jgo
} >}F? <JB
public String getCountType(){ DM2Q1Dh3
return countType; $'$>UFR
} R|t;p!T
public int getCountId(){ # ,P(isEZ"
return countId; $GF&x>]]
} HIPL!ss]
} kGD|c=K}
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CountCache.java `D)S-7BR
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/* R ]=SWE}U
* CountCache.java MhH);fn
* Z1]"[U[;
* Created on 2007年1月1日, 下午5:01 q)Je.6$#X
* \UtS>4w\
* To change this template, choose Tools | Options and locate the template under l%bq2,-%
* the Source Creation and Management node. Right-click the template and choose fNEz
* Open. You can then make changes to the template in the Source Editor. |E|T%i^}./
*/ /'Bdq?!B&
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package com.tot.count; M,L@k
import java.util.*; +UaO<L
/** dP3VJ3+
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* @author oUS,+e
*/ nh|EZp]
public class CountCache { Spc&X72I
public static LinkedList list=new LinkedList(); W]~ZkQ|P
/** Creates a new instance of CountCache */ c'lIWuL)
public CountCache() {} B'/Icg.T
public static void add(CountBean cb){ Q=XA"R
if(cb!=null){ $9m5bQcV
list.add(cb); U$EM.ot
} <tQXK;
} 83xd@-czgh
} z9fNk%
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CountControl.java T`mEO\f
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/* ,^!Zm^4,
* CountThread.java />!!ch
*
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* Created on 2007年1月1日, 下午4:57 Znq(R8BMW
* )x9]xqoR
* To change this template, choose Tools | Options and locate the template under iDR6?f P
* the Source Creation and Management node. Right-click the template and choose >";%2u1
* Open. You can then make changes to the template in the Source Editor. "DzGBu\
*/ &}|0CR.(
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package com.tot.count; H>Sf[8w)%
import tot.db.DBUtils; UR\ZN@O
import java.sql.*; }9FD/
/** o5V`'[c
* x/[8Wi,yB
* @author K5+!(5V~
*/ &{hc
public class CountControl{ (mY(\mu}
private static long lastExecuteTime=0;//上次更新时间 -|$* l
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 e
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/** Creates a new instance of CountThread */ _AAx
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public CountControl() {} 3v G
public synchronized void executeUpdate(){ o[2Y;kP3*P
Connection conn=null; 1y(iE C
PreparedStatement ps=null; PgqECd)f
try{ |/2LWc?
conn = DBUtils.getConnection(); {!g?d<*
conn.setAutoCommit(false); Xv]*;Bq:SK
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); hX %s]"
for(int i=0;i<CountCache.list.size();i++){ TR|;,A[%v#
CountBean cb=(CountBean)CountCache.list.getFirst(); 4KZ SL:A
CountCache.list.removeFirst(); >5df@_'
ps.setInt(1, cb.getCountId()); )e#fj+>x)
ps.executeUpdate();⑴ `GP3D~
//ps.addBatch();⑵ 7ia"u+Y
} S{Rh'x\B
//int [] counts = ps.executeBatch();⑶ H.)fOctbO
conn.commit(); 8QPT\~
}catch(Exception e){ U=M#41J
e.printStackTrace(); UVnrDhd!0
} finally{ V~JBZ}`TG<
try{ 0\QYf0o
if(ps!=null) { |@OJ~5H/{
ps.clearParameters(); JPHUmv6
ps.close(); a{5H33JA
ps=null; .!!79 6hS
} \8
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}catch(SQLException e){} 1k0^6gE|
DBUtils.closeConnection(conn); ?V.ig
} W6hNJb
} 'wegipK~R
public long getLast(){ Bfu/9ad
return lastExecuteTime; T27:"LVw
} J,MT^ B
public void run(){ jg7d7{{SB
long now = System.currentTimeMillis(); R
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if ((now - lastExecuteTime) > executeSep) { }FuVY><l
//System.out.print("lastExecuteTime:"+lastExecuteTime); DI L)7K4
//System.out.print(" now:"+now+"\n"); "<7$2!
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ;CLR{t(N#V
lastExecuteTime=now; #}nBS-+
executeUpdate(); gCjH%=s
} @+[Y0_
else{ x|&[hFXD
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); zUvB0\{q
} L;
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} (D:KqGqoT
} Oz_b3r
//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 +>n.T
Iwnj'R7:
类写好了,下面是在JSP中如下调用。 DX]z=d)tc
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<% 4Sd+"3M
CountBean cb=new CountBean(); ABd153oW"
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $%lHj+(
CountCache.add(cb); VGq{y{(
out.print(CountCache.list.size()+"<br>"); cL-6M^!a
CountControl c=new CountControl(); X20<r?^,,
c.run(); ?z*W8b]'
out.print(CountCache.list.size()+"<br>"); BBaHMsr
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