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: IGAzE(
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CountBean.java i`OrMzL
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/* }o9Aa0$*$
* CountData.java ! ]Mc4!E
* \`,xgC9K
* Created on 2007年1月1日, 下午4:44 1:= `Y@.S
* w9#R'
* To change this template, choose Tools | Options and locate the template under xnq><4
* the Source Creation and Management node. Right-click the template and choose qA/bg
* Open. You can then make changes to the template in the Source Editor. YbMssd2Yg
*/ J%dJw}
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package com.tot.count; q3'o|pp
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/** j:1uP^.
* i!MwBYk
* @author c/u_KJFF-n
*/ }G1&]Wt_
public class CountBean { ;~sr$6
private String countType; y>(rZ^y&
int countId; PtKTm\,JL0
/** Creates a new instance of CountData */ Ws49ImCB
public CountBean() {} wy4q[$.4v
public void setCountType(String countTypes){ zb2K;%Qs+f
this.countType=countTypes; g*]E>SQ=
} \-.
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public void setCountId(int countIds){ J^I7BsZ
this.countId=countIds; amB@N6*
} \}inT_{g
public String getCountType(){ +|C[-W7Sw
return countType; :J(sXKr[C
} {&nV4c$v
public int getCountId(){ \/Ij7nD`l%
return countId; ZxS&4>.
} 3DoRE2}
} \].J-^=
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CountCache.java IG / $!*E
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/* ?TuI:dC
* CountCache.java "]]q} O?
* DcFCKji
* Created on 2007年1月1日, 下午5:01 R^Bk]
* *e<_; Kr?
* To change this template, choose Tools | Options and locate the template under _F8T\f|
* the Source Creation and Management node. Right-click the template and choose LC'2q*:'
* Open. You can then make changes to the template in the Source Editor. ( D}"&2
*/ U4_"aT>My
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package com.tot.count; 6f}e+ 80
import java.util.*; |R'i:=
/** ]M4NpUM
* ~Ob8i 1S>
* @author :k1$g+(lP
*/ Z! YpklZ?~
public class CountCache { iUNnPJh
public static LinkedList list=new LinkedList(); 5a$$95oL
/** Creates a new instance of CountCache */ #O</\|aH)i
public CountCache() {} !s-/0ugZ
public static void add(CountBean cb){ w<d*#$[,*
if(cb!=null){ &`PbO
list.add(cb); j+1KNH
} YkbO&~.
} L<@&nx
} YZ[%uArm
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CountControl.java ;?8Iys#
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/* ~N[|bPRmhE
* CountThread.java 3zb)"\(R
* ma7fDo0,`h
* Created on 2007年1月1日, 下午4:57 <R~KM=rL
* +{xG<Wkltz
* To change this template, choose Tools | Options and locate the template under FT_k^CC
* the Source Creation and Management node. Right-click the template and choose b]dxlj}
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* Open. You can then make changes to the template in the Source Editor. ^I./L)0=}
*/ |!5@xs*T
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package com.tot.count; Ai jUs*n 2
import tot.db.DBUtils; :bw6 k
import java.sql.*; 3"B+xbe=
/** '
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* U$$3'n
* @author 8DT@h8tA
*/
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public class CountControl{ AJWLEc4XK
private static long lastExecuteTime=0;//上次更新时间 !47A$sQ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 'WzUu MCx
/** Creates a new instance of CountThread */ Q=XA"R
public CountControl() {} $9m5bQcV
public synchronized void executeUpdate(){ U$EM.ot
Connection conn=null; <tQXK;
PreparedStatement ps=null; 83xd@-czgh
try{ TA9dkYlE/
conn = DBUtils.getConnection(); n8?KSQy$
conn.setAutoCommit(false); Hf.xd.Yw
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 7 FIFSt
for(int i=0;i<CountCache.list.size();i++){ ,^!Zm^4,
CountBean cb=(CountBean)CountCache.list.getFirst(); />!!ch
CountCache.list.removeFirst();
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ps.setInt(1, cb.getCountId()); Znq(R8BMW
ps.executeUpdate();⑴ )x9]xqoR
//ps.addBatch();⑵ U;>B7X;`E4
} >";%2u1
//int [] counts = ps.executeBatch();⑶ C[W5d~@;E
conn.commit(); YRu%j4Tx
}catch(Exception e){ ^~*8 @v""
e.printStackTrace(); FP@A;/c
} finally{ UR\ZN@O
try{ 1YFAr}M
if(ps!=null) { KY8^BjY@
ps.clearParameters(); Lo5Jb6nm
ps.close(); SZI7M"gf/+
ps=null; %8g$T6E[<2
} 0c-QIr}m
}catch(SQLException e){} 2:n|x5\H
DBUtils.closeConnection(conn); ,FS?"Ni
} )PHl>0i!
} ;_wMWl0F
public long getLast(){ ],$6&Cm
return lastExecuteTime; &?v#| qIh
} {z-NlH
public void run(){ }7&\eV{qU
long now = System.currentTimeMillis(); mf#fA2[
if ((now - lastExecuteTime) > executeSep) { f!^)!~
//System.out.print("lastExecuteTime:"+lastExecuteTime); MXh^dOWR
//System.out.print(" now:"+now+"\n"); l4DeX\ly7f
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); SUSc
lastExecuteTime=now; 0ZFB4GL
executeUpdate(); ^U"
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} vFR
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else{ #[C<
J#;
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); =sL(^UISl
} 9c:5t'Qt5.
} I S.F
} 4'_L W?DS
//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 s"#CkG
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类写好了,下面是在JSP中如下调用。 ]zX\8eHp!
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<% ^v#+PyW
CountBean cb=new CountBean(); kaV%0Of]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }t}38%1i
CountCache.add(cb); M2a}x+5'
out.print(CountCache.list.size()+"<br>"); [6oq##
CountControl c=new CountControl(); IBzHR[#,^
c.run(); O5c_\yv=
out.print(CountCache.list.size()+"<br>"); EP/&m|o|G
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