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: =*7K_M&
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CountBean.java ES[H^}|Gi
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/* 'M>QA"*48E
* CountData.java LeDty_
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* Created on 2007年1月1日, 下午4:44 MaDdiyeC
* 68
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* To change this template, choose Tools | Options and locate the template under 8"L#5MO t
* the Source Creation and Management node. Right-click the template and choose 4}@J]_]Z
* Open. You can then make changes to the template in the Source Editor. wQ
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*/ 'thWo wE
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package com.tot.count; Q>Rjv.1
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/** 5+*MqO>
* o$]wd*+
* @author (_h<<`@B
*/
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public class CountBean { )[&'\SOO
private String countType; ocCq$%Ka
int countId; #@s[!4)_I
/** Creates a new instance of CountData */ lXH?*
public CountBean() {} e P]L
public void setCountType(String countTypes){ #=mLQSiQ
this.countType=countTypes; yd#SB) &
} P_S^)Yo
public void setCountId(int countIds){ %5#ts/f
this.countId=countIds; ~NT2QY5!K
} LpwjP4vWJ
public String getCountType(){ ZbVo<p5* ]
return countType; 77D>;90>?
} jFbj)!;
public int getCountId(){ H9}z0VI
return countId; ;}v#hKC~
} "M#A `b
} jdz]+Q`jq
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CountCache.java }+/j /es{]
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/* jcrLUs+\
* CountCache.java Jg} w{,
* 'sb&xj`d
* Created on 2007年1月1日, 下午5:01 O# n<`;W
* !C13E lf
* To change this template, choose Tools | Options and locate the template under ZfM DyS$.
* the Source Creation and Management node. Right-click the template and choose MIa#\tJj
* Open. You can then make changes to the template in the Source Editor. {k
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*/ T<:mG%Is
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package com.tot.count; HK_Vk\e
import java.util.*; = BcKWC
/** []^fb,5a
* <'WS -P%U
* @author M_
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*/ O5X@'.#rU
public class CountCache { 8EbJ5wu/%S
public static LinkedList list=new LinkedList(); ?|4Y(0N
/** Creates a new instance of CountCache */ JZ=ahSi
public CountCache() {} gY!+x=cx0
public static void add(CountBean cb){ P){b"`f
if(cb!=null){ dsJMhB_41U
list.add(cb); :g&9v_}&K{
} s{g^K#BoFi
} R( 2,1f=d
} 7]\_7L|>]
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CountControl.java g$X4ZRSel
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/* 8v{0=9,Z
* CountThread.java 'PO+P~|oa&
* }4$k-,1S
* Created on 2007年1月1日, 下午4:57 'Cr2&
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* w3hG\2)[HS
* To change this template, choose Tools | Options and locate the template under dgbqMu"
* the Source Creation and Management node. Right-click the template and choose -hy`Np
* Open. You can then make changes to the template in the Source Editor. %=w@c
*/ o2'^MxKb T
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package com.tot.count; {&u`d.Lk2p
import tot.db.DBUtils; 2!@ER i
import java.sql.*; hYvWD.c}
/** W20qn>{z
* n1Ic[cM}
* @author #_(t46
*/ tJ3Hg8;
public class CountControl{ 3lh^maQ]
private static long lastExecuteTime=0;//上次更新时间 L0^rw|Z%'
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Nw3K@Ge
/** Creates a new instance of CountThread */ FdwlRu G
public CountControl() {} T)CEcz
public synchronized void executeUpdate(){ 5~ip N/)E
Connection conn=null; -F->l5
PreparedStatement ps=null; s?Wkh`b
try{ N6R0$Br
conn = DBUtils.getConnection(); itU
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conn.setAutoCommit(false); y [jck:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !3*:6
for(int i=0;i<CountCache.list.size();i++){ }c]u'a!4
CountBean cb=(CountBean)CountCache.list.getFirst(); P<E!ix
CountCache.list.removeFirst(); =|j~*6Hd
ps.setInt(1, cb.getCountId()); ta
ps.executeUpdate();⑴ b^s>yN
//ps.addBatch();⑵ tNbL)
} A_pcv7=@
//int [] counts = ps.executeBatch();⑶ sKCfI]
conn.commit(); <>l!
}catch(Exception e){ g&]n:qx
e.printStackTrace(); -a+oQP]O
} finally{ R?Ys%~5
try{ jhx @6[
if(ps!=null) { 6s<w}O
ps.clearParameters(); 5Sh.4A\
ps.close(); %^qf0d*
ps=null; m[w 8|[
} EJByYk
}catch(SQLException e){} M[:},?ah0
DBUtils.closeConnection(conn); [&MhAzF
} hLo'q^mGr
} B[IqLD'6
public long getLast(){ Z*Lv!6WS
return lastExecuteTime; h*lU&8)m\
} uP.[,V0@^
public void run(){ HYcwtw6
long now = System.currentTimeMillis(); i_'u:P<t
if ((now - lastExecuteTime) > executeSep) { KQulz
//System.out.print("lastExecuteTime:"+lastExecuteTime); IpYw<2'
//System.out.print(" now:"+now+"\n"); 1)N~0)dO
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); u^X,ASkQ
lastExecuteTime=now; -.
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executeUpdate(); 2;`F`}BA
} \L]T|]}(
else{ y%Wbm&h
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} #U?=D/
} U#gv ~)\k
} D//uwom
//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 gZ 6Hj62D
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类写好了,下面是在JSP中如下调用。 Y(97},
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<% g@s'-8}X^
CountBean cb=new CountBean(); ,/1[(^e
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); iosL&*'8
CountCache.add(cb); :G/.h[\R|
out.print(CountCache.list.size()+"<br>"); Op
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CountControl c=new CountControl(); HLYo+;j3|
c.run(); N1l&$#Fr!s
out.print(CountCache.list.size()+"<br>"); *{%d{x}l
%>