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: ZMbv1*Vt
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CountBean.java `a]
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/* MwiT1sB~
* CountData.java #*5A]"k
* m,'u_yK
* Created on 2007年1月1日, 下午4:44 gQ&FO~cr
* w!h!%r
* To change this template, choose Tools | Options and locate the template under [ $B
* the Source Creation and Management node. Right-click the template and choose !}U&%2<69
* Open. You can then make changes to the template in the Source Editor. F e8xOo6
*/ 3rs=EMz:w
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package com.tot.count; -v`;^X
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/** k{uc%6s
* V0"UFy?i
* @author JWC{ "6
*/ !YCYmxw#
public class CountBean { L[D}pL=
private String countType; ZVViu4]?y
int countId; ^*RmT
/** Creates a new instance of CountData */ q_JES4ofx
public CountBean() {} Y8(g8RN
public void setCountType(String countTypes){ dKhDO`.s
this.countType=countTypes; D.X%wJ8
} _.zW[;84b
public void setCountId(int countIds){ wtaeF+u-R-
this.countId=countIds; *joM[ML` 6
} iN<Tn8-YH6
public String getCountType(){ a>6!?:Rj
return countType; *SLv$A
} 5s`NR<|2L
public int getCountId(){ m%ak ]rv([
return countId; a,!c6'QE
} d-lC|5U%
} p^^E(<2
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CountCache.java o^biO!4,
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/* (eFHMRMv~
* CountCache.java 5_#wOz0u$
* Y ~xcJH
* Created on 2007年1月1日, 下午5:01 ]=7}Y%6
* l\JoWL
* To change this template, choose Tools | Options and locate the template under )FYz*:f>&
* the Source Creation and Management node. Right-click the template and choose mKfT4t
* Open. You can then make changes to the template in the Source Editor.
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*/ =T!iM2
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package com.tot.count; 4cl}ouG
import java.util.*; ZF>zzi+@
/** b1R%JY7/S
* 6l<q
* @author ==~X8k|{E
*/ 9H`Q
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public class CountCache { gM '_1zs
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public static LinkedList list=new LinkedList(); _}8O15B|
/** Creates a new instance of CountCache */ PH^AT<U:T
public CountCache() {} !D!Q]M5oU
public static void add(CountBean cb){ eE '\h
if(cb!=null){ +m^ gj:yL
list.add(cb); QQj)"XJ29
} ?v\A&d
} K]1A,Q
} mY+Jju1
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CountControl.java ] K3^0S/
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/* n>"0y^v
* CountThread.java 5(]=?$$*t
* mR)Xq=
* Created on 2007年1月1日, 下午4:57 VE`5bD+%e
* nn5tOV}QE
* To change this template, choose Tools | Options and locate the template under eF823cH2x_
* the Source Creation and Management node. Right-click the template and choose *0^!%Y'/4
* Open. You can then make changes to the template in the Source Editor. T8bk \\Od
*/ /PafIq
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package com.tot.count; ~xerZQgc
import tot.db.DBUtils; [Abq("9p\
import java.sql.*; d,tGW
/** %wzDBsX
* 9nN$%(EO5;
* @author _0Qp[l-
*/ 2v\,sHw+-
public class CountControl{ wM9HZraB<
private static long lastExecuteTime=0;//上次更新时间 @GNNi?EY
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 i7_Nv
/** Creates a new instance of CountThread */ U-&dn%Sq
public CountControl() {} |3<tDq@+
public synchronized void executeUpdate(){ ]%>7OH'
Connection conn=null; ry)g<OA
PreparedStatement ps=null; ;x^WPYEj
try{ N_Q)AXr)
conn = DBUtils.getConnection(); P:,'
conn.setAutoCommit(false); >\6Tm
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); P/6$T2k_
for(int i=0;i<CountCache.list.size();i++){ SVB> 1s9F
CountBean cb=(CountBean)CountCache.list.getFirst(); q~ ]S5
CountCache.list.removeFirst(); ux`)jOQ`Y]
ps.setInt(1, cb.getCountId()); <&^P1x<x
ps.executeUpdate();⑴ |Ii[WfFA|J
//ps.addBatch();⑵ R9@Dd
} E%8Op{zv_
//int [] counts = ps.executeBatch();⑶ v'na{"
conn.commit(); GrPKJ~{6
}catch(Exception e){
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e.printStackTrace(); {Rc mjI7
} finally{ o
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try{ X67^@~l
if(ps!=null) { R-QSv$
ps.clearParameters(); Yz7H@Y2i
ps.close(); cetHpU,
ps=null; UVa:~c$U4
} H2[VZ&Pg
}catch(SQLException e){} 7~&
DBUtils.closeConnection(conn); r*_z<^d
} goBl~fqy0
} IC"lsNq52
public long getLast(){ {x_SnZz &
return lastExecuteTime; #@%DY*w]v
} iXLODuI
public void run(){ a4{~.Mp
long now = System.currentTimeMillis(); sT8(f=^)8F
if ((now - lastExecuteTime) > executeSep) { T6mbGE*IeE
//System.out.print("lastExecuteTime:"+lastExecuteTime); Uao8#<CkvJ
//System.out.print(" now:"+now+"\n"); 0i/!by{@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); jEU`ko_
lastExecuteTime=now; Xf
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executeUpdate(); v3\
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} 3<F\5|
else{ .Z?@;2<l
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); T<XGG_NOl
} 3mef;!q
} 8[v9|r
} y950Q%B]
//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 GO&~)Vh&7
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类写好了,下面是在JSP中如下调用。 >I*)0tE
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<% oW
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CountBean cb=new CountBean(); f
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); z3-A2#c
CountCache.add(cb); j}s<Pn%4
out.print(CountCache.list.size()+"<br>"); : ;l9to
CountControl c=new CountControl(); AUk-[i
c.run(); ~V34j:
out.print(CountCache.list.size()+"<br>"); _L8|ZV./
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