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: b~:)d>s8wY
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CountBean.java {.AN4
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/* _.V5-iN
* CountData.java ~5%3]
* JZ`h+fAt
* Created on 2007年1月1日, 下午4:44 g=Xy{Vm
* UCfouQ Cj
* To change this template, choose Tools | Options and locate the template under W}TP(~x'N
* the Source Creation and Management node. Right-click the template and choose (?R!y -
* Open. You can then make changes to the template in the Source Editor. M(K7xx+G
*/ .\ fpjQW
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package com.tot.count; *nJ,|T
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/** >4Tk#+%Jj
* _v 0iH
* @author E] /2u3p
*/ .x,y[/[[)
public class CountBean { y,|2hrj/0E
private String countType; s9CmR]C
int countId; CZu=/8?
/** Creates a new instance of CountData */ wzju)q S
public CountBean() {} XF)N_}X^
public void setCountType(String countTypes){ 1~K'r&
this.countType=countTypes; Bt}90#
} jIe
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public void setCountId(int countIds){ ~ E6e~
this.countId=countIds; n:/!{.
} N WF h<
public String getCountType(){ =KOi#;1
return countType; v/rBjUc+X
} dt"/4wCO
public int getCountId(){ lqmQQ*Z
return countId; 2{~`q
} >\<eR]12
} Y`]P&y
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CountCache.java Y=G`~2Pr=
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/* {!wW,3|Pu
* CountCache.java HYGd
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* }#ta3 x
* Created on 2007年1月1日, 下午5:01 IS(F_< .
* qm><}N7f
* To change this template, choose Tools | Options and locate the template under GLecBF+>F
* the Source Creation and Management node. Right-click the template and choose ;xz_H$g
* Open. You can then make changes to the template in the Source Editor. lkTA"8d
*/ 1 mJUlx
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package com.tot.count; sYDav)L.
import java.util.*; ;k `51=Wi
/** !;*flr`/
* mih}?oi
* @author ,:L^vG@*
*/ Lr:n
public class CountCache { B//*hH >F
public static LinkedList list=new LinkedList(); -+1O*L!
/** Creates a new instance of CountCache */ )SJM:E
public CountCache() {} 3 5.&!4}
public static void add(CountBean cb){ ( `bb1gz
if(cb!=null){ $%DoLpE>
list.add(cb); j]kgdAq>
} )GVTa4}p
} [T =>QS@g
} NN'pBUR
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CountControl.java l3 F$5n
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/* 'pIrwA^6N
* CountThread.java \ . #Y
* N7lg6$s Aj
* Created on 2007年1月1日, 下午4:57 Ro9:kEG$
* 6Y]P7j
* To change this template, choose Tools | Options and locate the template under ,.ivdg(/
* the Source Creation and Management node. Right-click the template and choose &nr{-][
* Open. You can then make changes to the template in the Source Editor. ^P~,bO&H.Z
*/ vi^YtA
_";w*lg}
package com.tot.count; PVlCj
import tot.db.DBUtils; o5&b'WUJ=
import java.sql.*; K1J |\!o
/** <lIm==U<-
* e16H@
* @author fT Pm
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*/ tkk8b6%h?p
public class CountControl{ pp(09y`]
private static long lastExecuteTime=0;//上次更新时间 q&>fKS nKs
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1O0. CC,p
/** Creates a new instance of CountThread */ G) KI{D
public CountControl() {} >qNpY(Ql
public synchronized void executeUpdate(){ XV%R Mr6
Connection conn=null; 59 g//;35@
PreparedStatement ps=null; @, fvWNI
try{ 80lhhqRC
conn = DBUtils.getConnection(); 2qE_SSXn
conn.setAutoCommit(false); O D N_i
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Yz0fOX
for(int i=0;i<CountCache.list.size();i++){ R_/;U&R
CountBean cb=(CountBean)CountCache.list.getFirst(); :$u[1&6
CountCache.list.removeFirst(); 6~0kb_td
ps.setInt(1, cb.getCountId()); <bhGpLh-E
ps.executeUpdate();⑴ s(Gs?6}>T
//ps.addBatch();⑵ +d=f_@i
} cS YCMQ1ro
//int [] counts = ps.executeBatch();⑶ "1Hn?4nz5
conn.commit(); lG0CCOdQ
}catch(Exception e){ PZ6R+n8
e.printStackTrace(); :n13v@q
} finally{ [Lji LKW
try{ Xykoq"dbb
if(ps!=null) { ^"|q~2
ps.clearParameters(); #KoI8U"
ps.close(); |g}r
ps=null; AFL'Ox]0
} LqD7SJ}/f
}catch(SQLException e){} W"@'}y
DBUtils.closeConnection(conn); ~fD\=- S1
} DTA$,1JuD
} x f{`uHa8
public long getLast(){ 9O&gR46.
return lastExecuteTime; R[\1Kk(Zo
} y lczM^@
public void run(){ 6BA$v-VVU
long now = System.currentTimeMillis(); ?`xF>P]M
if ((now - lastExecuteTime) > executeSep) { N,XjZ26
//System.out.print("lastExecuteTime:"+lastExecuteTime); @Hp%4$=
//System.out.print(" now:"+now+"\n"); x[TLlV:{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); WxYEu+_
lastExecuteTime=now; Y J,"@n_
executeUpdate(); iNkN'("
} ~
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else{ QlB9m2XB
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); )=gU~UV
} nU{Qi;0
} ?0dmw?i
} }[|9vF"g.y
//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 [g}#R#Y)
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类写好了,下面是在JSP中如下调用。 ^"I@ 8 k
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<% hC"'cUrcN
CountBean cb=new CountBean(); bR~Xog
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); F;`c0ja]
CountCache.add(cb); HFjSM~
out.print(CountCache.list.size()+"<br>"); 8*b{8%<K
CountControl c=new CountControl(); T&/n.-@nk
c.run(); cz/E
out.print(CountCache.list.size()+"<br>"); Q{S{|.w-
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