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: t3>$|}O]t
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CountBean.java 7P*Z0%Q
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/* lD3)TAW@o
* CountData.java _z]v<,=3M
* I4~^TrznRa
* Created on 2007年1月1日, 下午4:44 }e2F{pQ
* WsB3SFNG
* To change this template, choose Tools | Options and locate the template under ^1VbH3M
* the Source Creation and Management node. Right-click the template and choose e1uMR-Q
* Open. You can then make changes to the template in the Source Editor. Pb4q`!
*/ &I)\*Ue2t
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package com.tot.count; }p*?1N
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/** h.^o)T
* uP6-cs
* @author TPK@*9rI
*/ SUu >6'LN
public class CountBean { TvM24Orct
private String countType; Sn ^Aud
int countId; jsZY{s=
/** Creates a new instance of CountData */ pl\b-
public CountBean() {} 4>k
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public void setCountType(String countTypes){ -[$&s FD
this.countType=countTypes; JY@X2'>v/
} g@u;Y5
public void setCountId(int countIds){ O<`,,^4w/
this.countId=countIds; -l JYr/MSL
} xFwXW)
public String getCountType(){ 27iy4(4
return countType; @h(!<Ux_
} w[sR7T9*
public int getCountId(){ kwF] TO
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return countId; [>p6
} b0YNac.l
} ~p^7X2% !
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CountCache.java )E~_rDTl
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/* Ut_mrb+W
* CountCache.java nsl*Dm"*F
* 9A+M|;O
* Created on 2007年1月1日, 下午5:01 9GPb$gtx
* j{"[Ec
* To change this template, choose Tools | Options and locate the template under "Z~`e]>
* the Source Creation and Management node. Right-click the template and choose Pw
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* Open. You can then make changes to the template in the Source Editor. o&,Y<$!:VH
*/ R9vY:oN%
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package com.tot.count; 0I^Eo|
import java.util.*; cAibB&`~
/** ~bGnq,
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* `M)E* G
* @author ns26$bU
*/ gQR1$n0
public class CountCache { 9FNwpL'C
public static LinkedList list=new LinkedList(); @>:i-5
/** Creates a new instance of CountCache */ df
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public CountCache() {} OHhs y|W
public static void add(CountBean cb){ I+~bCcgPi
if(cb!=null){ 9`INC~h
list.add(cb); z5 pc3:
} OAVQ`ek
} E*^9|Y[
} SUc6/'Rdr
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CountControl.java ]ViOr8u
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/* HL8(lPgS
* CountThread.java ]738Z/)^
* 3cHtf
* Created on 2007年1月1日, 下午4:57 uP Rl[tS0
* /n8psj
* To change this template, choose Tools | Options and locate the template under pg!`SxFD
* the Source Creation and Management node. Right-click the template and choose 1I
\tu
* Open. You can then make changes to the template in the Source Editor. yLB~P7K
*/ `oVB!eapl
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package com.tot.count; ]?#
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import tot.db.DBUtils; gDv$DB8-
import java.sql.*; - `4Ty*K
/** \n;g2/VjO
* mmcdtVe
* @author _4!{IdR
*/ &SrGh$:X
public class CountControl{ UM`nq;>
private static long lastExecuteTime=0;//上次更新时间 .HCaXFW
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 R=Ymo.zs6
/** Creates a new instance of CountThread */ 5v3RVaqZ
public CountControl() {} O8[k_0@
public synchronized void executeUpdate(){ 6y9C@5p}B
Connection conn=null; &N9IcNP
PreparedStatement ps=null; 9N1#V
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try{ [9HYO
conn = DBUtils.getConnection(); 117c,yM0
conn.setAutoCommit(false); 8H_l[/
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $W*|~}F/Ap
for(int i=0;i<CountCache.list.size();i++){ F"v:}Vy|
CountBean cb=(CountBean)CountCache.list.getFirst(); 9M]^l,
CountCache.list.removeFirst(); |=u96G~N
ps.setInt(1, cb.getCountId()); 6+)x7g1PL
ps.executeUpdate();⑴ shNE~TA
//ps.addBatch();⑵ k{{hZ/om
} p_9g|B0D
//int [] counts = ps.executeBatch();⑶ lZvS0JS
conn.commit(); C/y(E|zC$
}catch(Exception e){ %i3{TL
e.printStackTrace(); Zd+>
} finally{ c(E,&{+E
try{ /:KQAM0
if(ps!=null) { 1I
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ps.clearParameters(); B#:E?a;{
ps.close(); L&'l3|
ps=null; L:i+}F;M)s
} gZ*hkKN6
}catch(SQLException e){} DU`v J2
DBUtils.closeConnection(conn); 'QnW9EHLF
} *73AAA5LKa
} Y!it!9
public long getLast(){ Pr2;Kp
return lastExecuteTime; I5Q~T5Ar
} 5v+L';wx[T
public void run(){ ?eVj8 $BQo
long now = System.currentTimeMillis(); %!yxC
if ((now - lastExecuteTime) > executeSep) { %b9fW
//System.out.print("lastExecuteTime:"+lastExecuteTime); Zsgi{
//System.out.print(" now:"+now+"\n"); 716hpj#*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); OiF ]_"
lastExecuteTime=now; RJLFj
executeUpdate(); A-;^~I
} ^F&A6{9f/h
else{ Op90NZI#K
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); );!dg\U
} `^zQ$au'u
} FTbtAlqh<
} 4]]b1^vVj
//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 jP7w6sk
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类写好了,下面是在JSP中如下调用。 Wkww&Y
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<% w0X$rl1
CountBean cb=new CountBean(); >R#9\/s
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Stt* 1gT
CountCache.add(cb); MorW\7-}
out.print(CountCache.list.size()+"<br>"); I X?@~'
CountControl c=new CountControl(); n{3|E3
c.run(); L*v93;|s
out.print(CountCache.list.size()+"<br>"); 9[Y*k^.!
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