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: Q&wBX%@^L
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CountBean.java ?
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/* cLamqZf3
* CountData.java MECR0S9
* 7 0KZXgBy_
* Created on 2007年1月1日, 下午4:44 rsrv1A=t?
* O#9Q+BD
* To change this template, choose Tools | Options and locate the template under jk) U~KGcg
* the Source Creation and Management node. Right-click the template and choose xU)~)eK
* Open. You can then make changes to the template in the Source Editor. P||u{]vU
*/ brZ3T`p+.P
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package com.tot.count; Ey)ox$
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/** y![h
* W&GDE
* @author x'}{^'}/
*/ m`n51i{U
public class CountBean { 0\u_\%[
private String countType; WpRi+NC}ln
int countId; CKj3-rcF(
/** Creates a new instance of CountData */ A*W QdY
public CountBean() {} IhUuL0
public void setCountType(String countTypes){ a]75z)XR
this.countType=countTypes; wtMS<$
} !! #\P7P
public void setCountId(int countIds){ 8iq~ha$]|
this.countId=countIds; jt?R
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} z^~fVl
public String getCountType(){ Zuwd(q
return countType; BC&Et62*
} g~N)~]0{
public int getCountId(){ ~KEnZa0
return countId; U edh4qa
} >C@fSmnOM
} a ipvG
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CountCache.java gn7pIoN
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/* 3vDV
* CountCache.java ;9d(GP}eE
* V.;0F%zks5
* Created on 2007年1月1日, 下午5:01 `Q}.9s_ri
* julAN$2
* To change this template, choose Tools | Options and locate the template under {_PV~8u
* the Source Creation and Management node. Right-click the template and choose VAV@Qn
* Open. You can then make changes to the template in the Source Editor. Wu%;{y~#}
*/ (,HAOs
}?"f#bI
package com.tot.count; Dr<% Lr
import java.util.*; 90M:0SH
/** ]oZ$,2#;~
* h|_G2p^J+"
* @author M`AbH19
*/ 1 BVivEG
public class CountCache { ;z!~-ByzL
public static LinkedList list=new LinkedList(); 2x'JR yef
/** Creates a new instance of CountCache */ (iH5F9WO
public CountCache() {} $O7>E!uVD
public static void add(CountBean cb){ (]'4_~e
if(cb!=null){ O]i}r`E8,
list.add(cb); eRC@b^~
}
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} IN),Lu0K
} {U7j
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CountControl.java XW`&1qx
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/* QfRt3\^`
* CountThread.java \Ui8Sgeei
* v:<u0B-)$
* Created on 2007年1月1日, 下午4:57 j =[Td
* (~,Q-w"
* To change this template, choose Tools | Options and locate the template under D6c4tA^EO
* the Source Creation and Management node. Right-click the template and choose 8V.x%T
* Open. You can then make changes to the template in the Source Editor. 4e1Zyi!
*/ d(42ob.Tr
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package com.tot.count; P#"vlNa
import tot.db.DBUtils; Qq^>7OU>Co
import java.sql.*; m`E8gVC
/** ]@>bz
* Uo5l
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* @author b'uH4[zX%
*/ kQwBrb4
public class CountControl{ EVrOu""
private static long lastExecuteTime=0;//上次更新时间 #W'jNX,h
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 >=[w{Vn'Mf
/** Creates a new instance of CountThread */ ,]1K^UeZ
public CountControl() {} h,0mJj-ma
public synchronized void executeUpdate(){ `QAotSO+
Connection conn=null; jcv3ES^
PreparedStatement ps=null; :1=mNrg
try{ E.4`aJ@>d
conn = DBUtils.getConnection(); Q_qc_IcM y
conn.setAutoCommit(false); mp%i(Y"vp
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); o1-Zh!*a*
for(int i=0;i<CountCache.list.size();i++){ <JDkvpckx.
CountBean cb=(CountBean)CountCache.list.getFirst(); zr2%|YF
CountCache.list.removeFirst(); a*KB'u6&
ps.setInt(1, cb.getCountId()); cPkN)+K
ps.executeUpdate();⑴ dy#dug6j
//ps.addBatch();⑵ qP *$wKY,
} :1s6h%evrT
//int [] counts = ps.executeBatch();⑶ "PLZZL$+
conn.commit(); qGr(MDLc
}catch(Exception e){ KKl8tI\u~
e.printStackTrace(); 0:Ak4L6k
} finally{ 9^3y\@ m
try{ aZ@Ke$jD
if(ps!=null) { n<y!@p^X
ps.clearParameters(); I(
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ps.close(); \{P(s:
ps=null; S_ e }>-
} 7Oru{BQ">
}catch(SQLException e){} sq\oatMw[
DBUtils.closeConnection(conn); j^ex5A.&
&
} /@Y/(+DE
} J$v0
public long getLast(){ wYOSaGyZ0I
return lastExecuteTime; [D^KM|I%+
} }| (KI
public void run(){ KPs5? X
long now = System.currentTimeMillis(); jx+%X\zokA
if ((now - lastExecuteTime) > executeSep) { A#f@0W:
//System.out.print("lastExecuteTime:"+lastExecuteTime); Tr-gdX ;
//System.out.print(" now:"+now+"\n"); VD<W
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9Psy$
lastExecuteTime=now;
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executeUpdate(); PGOi#x
} )CSb\
else{ AFF7fK
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /t01z~_
} e{>X2UNW
} Wx;:_F7'\
} .3t[M0sd
//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 vLXN{ ]
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类写好了,下面是在JSP中如下调用。 tz6d}$
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<% 8~u#?xs6
CountBean cb=new CountBean(); gV91=Pj
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); C;y3?+6P$
CountCache.add(cb); O)kC[e4
out.print(CountCache.list.size()+"<br>"); kViX FPW
CountControl c=new CountControl(); CZS{^6Ye
c.run(); )K4 |-<i
out.print(CountCache.list.size()+"<br>"); ,9`sC8w|
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