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: '7O{*=`oj
Cr
V2 V)|G
CountBean.java @6i8RmOu}
&=6cz$]z
/* UVoLHd
* CountData.java 23u1nU[0
* 4MF}FS2)
* Created on 2007年1月1日, 下午4:44 b/n8UxA
* n[MIa]dK
* To change this template, choose Tools | Options and locate the template under o,''f_tRQ|
* the Source Creation and Management node. Right-click the template and choose VATXsD
* Open. You can then make changes to the template in the Source Editor. ^b|Nw:
*/ =Zb"T5E
3qxG?G N
package com.tot.count; jFPE>F7-M
}JpslY*aS
/** Edn$0D68u_
* hOrk^iYN=
* @author +k(3+b$S-
*/ 9^
*ZH1
public class CountBean { ~a8G 5M
private String countType; 5S-o
2a
int countId; YL&b9e4
/** Creates a new instance of CountData */ ixJ20A7
public CountBean() {} +v[$lh+
public void setCountType(String countTypes){ Oz9Mqcx
this.countType=countTypes; eI=Y~jy
} ?C>VB+X}y
public void setCountId(int countIds){ m^oi4mV
this.countId=countIds; ?o(X0
} \|>`z,;
public String getCountType(){ a^}P_hg}-
return countType; J0*]6oD!
} A*;^F]~'
public int getCountId(){ g;Sg
2
return countId; )6R#k8'ERr
} ^(m6g &$(
} [?f.0q
g
/ @yK
CountCache.java UG?C=Tf
N5an9r&z(1
/* (7jB_ p%
* CountCache.java n\ ',F
* io33+/
* Created on 2007年1月1日, 下午5:01 GqD!W8+
* Lvj5<4h;
* To change this template, choose Tools | Options and locate the template under m<'xlF
* the Source Creation and Management node. Right-click the template and choose Md?bAMnG+}
* Open. You can then make changes to the template in the Source Editor. .8PO7#
*/ 't%%hw-m}
%WT:RT_
package com.tot.count; $J0~2TV<
import java.util.*; Gx* 0$4xJ3
/** [.Wt,zrE
* cxJK>%84
* @author M^JZ]W(
*/ dVGUhXN6
public class CountCache { ,t&-`U]AX
public static LinkedList list=new LinkedList(); ~md|k
/** Creates a new instance of CountCache */ ^FMa8;'o
public CountCache() {} .rB;zA;4S)
public static void add(CountBean cb){ n
ua8y(W
if(cb!=null){ I~]mX;
list.add(cb); MbF e1U]B
} #|_UA}Y
} AW;)_|xM
} F#bo4'&>@
68GGS`&
CountControl.java lgqL)^8A
E!~2\qKT
/* `8.32@rUB.
* CountThread.java 42LXL*-4
* j.N\U#3KK
* Created on 2007年1月1日, 下午4:57 8*PAgPj a
* wfTv<WG,.E
* To change this template, choose Tools | Options and locate the template under ?uX6X'-
* the Source Creation and Management node. Right-click the template and choose U9[A(
* Open. You can then make changes to the template in the Source Editor. ec[[OIO
*/ /\$|D&e
tKsM}+fq
package com.tot.count; SF7b1jr
import tot.db.DBUtils; g2>u]3&W
import java.sql.*; wJR i;fvi
/** _
*s
* qe"6#@b *|
* @author ;AB ,:*
*/ rJQ|Oi&1i
public class CountControl{ GJt9hDM$0
private static long lastExecuteTime=0;//上次更新时间 3N*C]
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 NE%yv,B
/** Creates a new instance of CountThread */ (Dh;=xG
public CountControl() {} S!!\!w>N
public synchronized void executeUpdate(){ 2/4x]i
H*
Connection conn=null; ts\>_/
PreparedStatement ps=null; S,9WMti4x
try{ 14YV#o:
conn = DBUtils.getConnection(); -x\l<\*
conn.setAutoCommit(false); [*ovYpj^
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); V//q$/&8(
for(int i=0;i<CountCache.list.size();i++){ d?y\~<
CountBean cb=(CountBean)CountCache.list.getFirst(); `"mK\M
CountCache.list.removeFirst(); SWO!E
ps.setInt(1, cb.getCountId()); Afhx`J1KO
ps.executeUpdate();⑴ :XZom+>2n
//ps.addBatch();⑵ UkbQ'P+oS
} R/cq00g
//int [] counts = ps.executeBatch();⑶ +pViHOJu&V
conn.commit(); IeI%X\G
}catch(Exception e){ NWwtq&pz2
e.printStackTrace(); |Pl{Oo+
} finally{ [Q_|6Di
try{ Ul0<Zxv
if(ps!=null) { UZ3Aq12U}a
ps.clearParameters(); HtYR 0J
ps.close(); 4m!3P"$
ps=null; cE>/iZc
} pz}hh^]t
}catch(SQLException e){} tUF]f6
DBUtils.closeConnection(conn); Zw
8b
-_
} J7^T!7V.
} xQ
3u
public long getLast(){ t\d;}@bl
return lastExecuteTime; M]TVaN$v#
} c
O>:n
public void run(){ uOqDJM'RM
long now = System.currentTimeMillis(); vS__*}^
if ((now - lastExecuteTime) > executeSep) { |F{E4mg(o
//System.out.print("lastExecuteTime:"+lastExecuteTime); rPvX8*)tV
//System.out.print(" now:"+now+"\n"); ,;pX.Ob U
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 'wV26Dm
lastExecuteTime=now; V="f)'S$
executeUpdate(); *LdH/C.LIf
} \#7%%>p=O'
else{ Riuv@i^6K
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); TFNU+
} y/VmjsN}
} 7$P(1D4
} M|=$~@9#X
//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 Nh/ArugP5P
9],"AjD
类写好了,下面是在JSP中如下调用。 vbh#[,lh
NfN6KDd]2L
<% i j;'4GzQL
CountBean cb=new CountBean(); z( [ $,e\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ,8?*U]}
CountCache.add(cb); 2czL 1Ci
out.print(CountCache.list.size()+"<br>"); abP?Dj&
CountControl c=new CountControl(); t1g%o5?;
c.run(); ui0(#2'h%
out.print(CountCache.list.size()+"<br>"); @5GP;3T
%>