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: RG1~)5AL~Y
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CountBean.java Ao~ZK[u
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/* a<9cj@h
* CountData.java WDc2Qt
* *&]x-p1m
* Created on 2007年1月1日, 下午4:44 b37P[Q3
* (,<&H;,8
* To change this template, choose Tools | Options and locate the template under {-;lcO D
* the Source Creation and Management node. Right-click the template and choose C50&SrnBU1
* Open. You can then make changes to the template in the Source Editor. oace!si
*/ ZWH?=Bk:
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package com.tot.count; s\A"B#9r
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/** |y=; #A
* HO%atE$>
* @author bkk1_X
*/ jkw:h0hX
public class CountBean { <+ 0cQq=2
private String countType; +Gv{Apd"
int countId; ,b!!h]t
/** Creates a new instance of CountData */ &(a#I]`9M
public CountBean() {} +^1E0@b%
public void setCountType(String countTypes){ 6yEYX'_
this.countType=countTypes; 7DaMuh~<
} tr3Rn :0]
public void setCountId(int countIds){ +rse,b&U(
this.countId=countIds; (GB2("p`
} MN1
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public String getCountType(){ Gu}
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return countType; _):V7Zv
} ~^jdiy5
public int getCountId(){ .1R:YNx{/
return countId; P9h]Bu
} rrBu6\D
} :l<)p;\
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CountCache.java f@U\2r
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/* CMI'y(GN
* CountCache.java -=_bXco}
* 5y]1v
* Created on 2007年1月1日, 下午5:01 vowU+Y
* wBlfQ
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* To change this template, choose Tools | Options and locate the template under {*WJ"9ujp]
* the Source Creation and Management node. Right-click the template and choose \z>Re$:
* Open. You can then make changes to the template in the Source Editor. q0|u vt"
*/ GCSR)i|
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package com.tot.count; R'bmE:nL
import java.util.*; ILdRN
/** +c&n7
* i
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* @author Fr{u=0 X
*/ Fl{:aq"3
public class CountCache { u;1/.`NPB
public static LinkedList list=new LinkedList(); P2J{Ml#
/** Creates a new instance of CountCache */ Exir?G} \
public CountCache() {} Cw`8[)=}o
public static void add(CountBean cb){ )X*?M?~\
if(cb!=null){ ~P&Brn"=Rs
list.add(cb); .KiJq:$H
} F\&Sn1>k
} =2&/Cn4
} S;a'@5
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CountControl.java _ 4:@+{
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/* [^wEKRt&
* CountThread.java fBCW/<Z
* E({+2}=1
* Created on 2007年1月1日, 下午4:57 u6&<Bv
* OU)~
02|\
* To change this template, choose Tools | Options and locate the template under ;A^0="x&
* the Source Creation and Management node. Right-click the template and choose e.pm`%5bO
* Open. You can then make changes to the template in the Source Editor. 1 o<l;:
*/ !:
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package com.tot.count; QoZ7l]^
import tot.db.DBUtils; -dX{ R_*
import java.sql.*; |Z%I3-z_DS
/** 3#fu;??1.
* 7P3PQ%:
* @author dD6I @N)X
*/ _isqk~ ul
public class CountControl{ 8#% Sq=/+M
private static long lastExecuteTime=0;//上次更新时间 Nxk3uF^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 zJ;K4)"j
/** Creates a new instance of CountThread */ HQi57QB
public CountControl() {} >7@kwj-f)
public synchronized void executeUpdate(){ =+um:*a.
Connection conn=null; a*4"j2j v
PreparedStatement ps=null; Lg[v-b=?I
try{ QF^ _4Yn
conn = DBUtils.getConnection(); YTBZklM
conn.setAutoCommit(false); 'qD5
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ogN/zIU+VA
for(int i=0;i<CountCache.list.size();i++){ cd8ZZ8L
CountBean cb=(CountBean)CountCache.list.getFirst(); Qd~M;L O"i
CountCache.list.removeFirst(); e">$[IhXtV
ps.setInt(1, cb.getCountId()); ;zy[xg.7
ps.executeUpdate();⑴ ejq2]^O4c
//ps.addBatch();⑵ J?/.|Y]e
} O6rrv,+_L
//int [] counts = ps.executeBatch();⑶ u<8 f;C_
conn.commit(); {"<6'2T3
}catch(Exception e){ ml7nt0{
e.printStackTrace(); B35zmFX|}N
} finally{ 9G8n'jWyY
try{ _4E .
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if(ps!=null) { W}+f}/&l
ps.clearParameters(); =GO/r;4
ps.close(); )c9]}:W&
ps=null; k<b`v&G
} U3SF'r8
}catch(SQLException e){} oicett=5
DBUtils.closeConnection(conn); P3[+c4
} HVb9YU+
} h&|wqna
public long getLast(){ iG<rB-"
return lastExecuteTime; HnvE\t9`
} RusC5\BUX
public void run(){ sA18f2
long now = System.currentTimeMillis(); tT7< V{i4
if ((now - lastExecuteTime) > executeSep) { 5j(3pV`_
//System.out.print("lastExecuteTime:"+lastExecuteTime); y w"Tw
//System.out.print(" now:"+now+"\n"); !\{&^,y
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 4Q0@\dR9
lastExecuteTime=now; X|.M9zIx
executeUpdate(); @g|Eb}t
} qwAN=3@
else{ nJ/ wtw
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); F?j;3@z[A
} 4m++>q
} r4Ygy/%
} ZdQm&?
//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 y^; =+Z
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类写好了,下面是在JSP中如下调用。 wK8/`{B9
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<% MWSx8R)PN
CountBean cb=new CountBean(); `!MyOI`qS
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Peha{]U
CountCache.add(cb); U_a)g
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out.print(CountCache.list.size()+"<br>"); %N)o*H&
CountControl c=new CountControl(); v4L#^Jw(^p
c.run(); j=v 1:E
out.print(CountCache.list.size()+"<br>"); '8~cf
%>