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: lr&a;aZp
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CountBean.java %E;'ln4h&,
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/* buHJB*?9
* CountData.java $3kH~3{]
* 7F~X,Dk_
* Created on 2007年1月1日, 下午4:44 9}
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* es0hm2HT3
* To change this template, choose Tools | Options and locate the template under sV*H`N')S
* the Source Creation and Management node. Right-click the template and choose hOK8(U0
* Open. You can then make changes to the template in the Source Editor. n~Lt\K:
*/ )D%~`,#pQ
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package com.tot.count; z` b,h\
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/** j![\& z
* ql~J8G9
* @author u_Z+;{]Pj
*/ e&>2
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public class CountBean { F_P~x(X
private String countType; 3o/[t
int countId; O^rD HFj,
/** Creates a new instance of CountData */ b|(:[nB
public CountBean() {} |JsZJ9W+J
public void setCountType(String countTypes){ _,*r_D61S
this.countType=countTypes; KqP#6^ _
} 4Wp=y
public void setCountId(int countIds){ ;mi%F3
this.countId=countIds; bcz:q/f}@
} 9:lFo=
public String getCountType(){ -trkA'ewZ
return countType; F((4U"
} _)iCa3z
public int getCountId(){ An0GPhC
return countId; yaX
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} cm+P]8o%{
} i"=\d
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CountCache.java NwfVL4Xg
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/* pQQH)`J|t
* CountCache.java gnHbb-<i,
* |5 ]X| v
* Created on 2007年1月1日, 下午5:01 cidP|ie^
* f%8C!W]Dm
* To change this template, choose Tools | Options and locate the template under "ocyK}l.?
* the Source Creation and Management node. Right-click the template and choose zKK9r~ M
* Open. You can then make changes to the template in the Source Editor. b~cZS[S
*/ l%=;
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package com.tot.count; V]?R>qhgu
import java.util.*; l}P=/#</T
/** u$`a7Lp,n
* lk =<A"^S
* @author !PE]C!*gv&
*/ 1AFA=t:]p
public class CountCache { NCD04U5y
public static LinkedList list=new LinkedList(); dgP3@`YS
/** Creates a new instance of CountCache */ #p{4^
public CountCache() {} c[s4EUG
public static void add(CountBean cb){ (w zQ2Dk
if(cb!=null){ ?r!o~|9|
list.add(cb); [<TrS/,)>
} "EJ~QCW*Yh
} -ze J#B)C
} x|29L7i
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CountControl.java 51.%;aY~z
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/* :fJN->wY^s
* CountThread.java /Gfw8g\}
* q0\6F^;M
* Created on 2007年1月1日, 下午4:57 Zgb!E]V[
* N)Z?Z+}h
* To change this template, choose Tools | Options and locate the template under OB}Ib]
* the Source Creation and Management node. Right-click the template and choose yF/j Fn
* Open. You can then make changes to the template in the Source Editor. aQI(Y^&%3
*/ BLJj(-
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package com.tot.count; -DAlRz#d,
import tot.db.DBUtils; 9Gz=lc[!7
import java.sql.*; =?`c=z3~i$
/** ]]Ufas9
* i{qgn%#}Y
* @author Yoll?_k+
*/ x$(f7?s] 1
public class CountControl{ 8a"%0d#
private static long lastExecuteTime=0;//上次更新时间 xe$_aBU
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ft
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/** Creates a new instance of CountThread */ EB|}fz
public CountControl() {} S5EK~#-L[
public synchronized void executeUpdate(){ ?Ss!e$jf
Connection conn=null; ]J]h#ZHx
PreparedStatement ps=null; {(?4!rh
try{ pmYHUj
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conn = DBUtils.getConnection(); !Xw5<J3L-
conn.setAutoCommit(false); (C)p9-,
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); |sZHUf_
for(int i=0;i<CountCache.list.size();i++){ eJ81-!)
CountBean cb=(CountBean)CountCache.list.getFirst(); j*m%*_kO
CountCache.list.removeFirst(); 9(<@O%YU
ps.setInt(1, cb.getCountId()); YZJyk:H\
ps.executeUpdate();⑴ 9-m=*|p
//ps.addBatch();⑵ GsM<2@?
} 0C,`h`
//int [] counts = ps.executeBatch();⑶ ,MIV=*
conn.commit(); 7 Fsay+a
}catch(Exception e){ @9|hMo
e.printStackTrace(); PeEj&4k
} finally{ U,1-A=Og{o
try{ ={Qi0Pvt
if(ps!=null) { |
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ps.clearParameters(); IO:G1;[/2L
ps.close(); Y\'}a+:@Ph
ps=null; +x}<IS8
} Fv`,3aNB
}catch(SQLException e){} 6;5Ss?ep
DBUtils.closeConnection(conn); iDrZc
} Q=yg8CQ
} [)X\|pO&
public long getLast(){ Z;)%%V%o
return lastExecuteTime; h2J
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} eh#(eua0/
public void run(){ vs{s_T7Mz]
long now = System.currentTimeMillis(); S:ztXhif>
if ((now - lastExecuteTime) > executeSep) { sdmT
//System.out.print("lastExecuteTime:"+lastExecuteTime); b5n'=doR/I
//System.out.print(" now:"+now+"\n"); lsNd_7k
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); iO;
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lastExecuteTime=now; ,~W|]/b<q
executeUpdate(); FJ?IUy 6
} Q#zmf24W
else{ _v]MsT-q
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); \xoP)Ub>
} 0#^v{DC
} <1M-Ro?5k
} ;t`&n['N>
//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 U:_^#\p
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类写好了,下面是在JSP中如下调用。 r",GC]
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<% NQ2E
CountBean cb=new CountBean(); D.XvG _
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $ L]lHji
CountCache.add(cb); ~61v5@
out.print(CountCache.list.size()+"<br>"); ~W]TD@w
CountControl c=new CountControl(); +=8VTCn?
c.run(); l1Fc>:o{
out.print(CountCache.list.size()+"<br>");
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