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: K%3{a=1
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CountBean.java 2_CJV
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/* mE"},ksg
* CountData.java #mW#K
* f<Xi/(
* Created on 2007年1月1日, 下午4:44 ?f4jqF~Fh
* J:G~9~V^
* To change this template, choose Tools | Options and locate the template under !z|a+{
* the Source Creation and Management node. Right-click the template and choose r"x/,!_E
* Open. You can then make changes to the template in the Source Editor. $uCY\xqZ
*/ w/Y6m.i1
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package com.tot.count; |>jlmaV
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/** T56%3i
* Y!fgc<]'&
* @author ILMXWw
*/ 5<mGG;F
public class CountBean { F8>J(7On
private String countType; qN(,8P\90
int countId; uYAMW{AT
/** Creates a new instance of CountData */ SZL('x,"^
public CountBean() {} GOj<>h}r
public void setCountType(String countTypes){ 6/l{e)rX2o
this.countType=countTypes; aT20FEZ;
} 7f#r&~=
public void setCountId(int countIds){ hVdPO
this.countId=countIds; #*x8)6Ct
} G_)(?
public String getCountType(){ ]}s'`44J9e
return countType; ]97`=,OUg
} mxkv{;ad
public int getCountId(){ Bxs0m]
return countId; g"|Z1iy|9
} |!\5nix3A>
} H3Sfz'
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CountCache.java \p{$9e;8yT
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/* t+%tN^87:
* CountCache.java ;.#l[
* 6qq{JbK
* Created on 2007年1月1日, 下午5:01 I>(-&YbC
* #Oq~ZV|<l
* To change this template, choose Tools | Options and locate the template under tk~<tqMq
* the Source Creation and Management node. Right-click the template and choose #SIIhpjA(
* Open. You can then make changes to the template in the Source Editor. 4I7;/ZgALQ
*/ #F25,:hY
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package com.tot.count; sB'Z9
import java.util.*; w;8VD`>[|
/** IPEJ7n49
* E6_.Q `!ll
* @author 9w08)2$Na
*/ ?0VETa ~m
public class CountCache { g*[DyIm
public static LinkedList list=new LinkedList(); NkL>ru!b9
/** Creates a new instance of CountCache */ o%V%@q H
public CountCache() {} z57|9$h}w
public static void add(CountBean cb){ 3_cZaru
if(cb!=null){ +y\mlfJ.-b
list.add(cb); J6W"t
} {((|IvP`
} V/CZcMY_
} #oQDt'
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CountControl.java 4M{]YZMw8
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/* H;=++Dh
* CountThread.java aH+n]J]
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* M<VZISu)dy
* Created on 2007年1月1日, 下午4:57 G@I/Dy
* O0cKmh6=
* To change this template, choose Tools | Options and locate the template under 4E~!$Ustx
* the Source Creation and Management node. Right-click the template and choose `(6g87h
* Open. You can then make changes to the template in the Source Editor. \Czuf
*/ ds|L'7
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package com.tot.count; p5PTuJ>q
import tot.db.DBUtils; 'awZ-$#
import java.sql.*; "5@k\?x"
/** V-.Nc#
* b am*&E%0K
* @author WEVV2BJ
*/
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public class CountControl{ :jUu_s}
private static long lastExecuteTime=0;//上次更新时间 ,8/Con|o
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 )mvD2]fK
/** Creates a new instance of CountThread */ %}x$YDO
public CountControl() {} .X)TRD#MW
public synchronized void executeUpdate(){ p:@JC sH=
Connection conn=null; R}VEq gq
PreparedStatement ps=null; oA'LQ
try{ 6y
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conn = DBUtils.getConnection(); ^ua8Ya
conn.setAutoCommit(false); r"aJ&~8::W
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @h$4M t7N
for(int i=0;i<CountCache.list.size();i++){ D^jyG6Ch
CountBean cb=(CountBean)CountCache.list.getFirst(); xY,W[?3CY
CountCache.list.removeFirst(); Y]-7T-*+t
ps.setInt(1, cb.getCountId()); bQelU
ps.executeUpdate();⑴ z=/xv},
//ps.addBatch();⑵ g (:%E
} x8q3 Njr
//int [] counts = ps.executeBatch();⑶ oM4Q_A n
conn.commit(); =n73bm
}catch(Exception e){ 5(V'<
e.printStackTrace(); e"]*^Q
} finally{ ?O!'ZZX
try{ }'.k
if(ps!=null) { vbT,!
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ps.clearParameters(); ZN]LJ4|xu
ps.close(); 1deNrmp%
ps=null; _J+p[=[L
} Pk6l*+"r<
}catch(SQLException e){} +o7Np|Ou
DBUtils.closeConnection(conn); ~Vf+@_G8`
} P.Uz[_&l6
} E"{2R>mU~
public long getLast(){ :6}y gL*i
return lastExecuteTime; aHzS>
} L
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public void run(){ EX.`6,:+2
long now = System.currentTimeMillis(); /y~ "n4CK~
if ((now - lastExecuteTime) > executeSep) { >lg-j-pV
//System.out.print("lastExecuteTime:"+lastExecuteTime); eGi[LJ)np
//System.out.print(" now:"+now+"\n"); t:?8I9d
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); FBCi,_
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lastExecuteTime=now; UNB'Xjp}@
executeUpdate(); Spt]<~
} 6IyD7PQ
else{ ~c*$w O\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); MsL*\)*s
} ;Fi(zl
} O%KP,q&}Y
} xct{Tv[FO
//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 ]*M-8_D
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类写好了,下面是在JSP中如下调用。 2V*<HlqOif
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<% Cb5Rr+K=
CountBean cb=new CountBean(); j$TTLFK1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); t"]+}]O
CountCache.add(cb); >hcze<^S
out.print(CountCache.list.size()+"<br>"); $aFCe}3b<
CountControl c=new CountControl(); :"pA0oB
c.run(); Qq. ht
out.print(CountCache.list.size()+"<br>"); ?k*%r;e>
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