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: t0f7dU3e;L
KH,f'`
CountBean.java J299mgB
V%4P.y
/* v9 \n=Z
* CountData.java V<5. 4{[G
* %ap]\o$^4
* Created on 2007年1月1日, 下午4:44 $*eYiz3Ue
* [CEV&B
* To change this template, choose Tools | Options and locate the template under qoZi1,i'
* the Source Creation and Management node. Right-click the template and choose s O#cJAfuu
* Open. You can then make changes to the template in the Source Editor. bqH
[-mu6
*/ d3z nb@7
ovN3.0tAI
package com.tot.count; HsYzIQLL
|"K%Tvxe
/** Do(G;D`h+_
* '|gsmO
* @author 7l7VT?<:
*/ &/[MWQ
public class CountBean { T"P}` mT
private String countType; ~U w<e~
int countId; oQ,n?on
/** Creates a new instance of CountData */ KGOhoiR9:C
public CountBean() {} }-:B`:K&
public void setCountType(String countTypes){ [NE!
this.countType=countTypes; >h%>s4W
} U~=?I)Ni
public void setCountId(int countIds){ 2W0nA t
this.countId=countIds; hbYstK;]Z
} Mo@{1K/9
public String getCountType(){ hYyIC:PXR
return countType; K3vZ42n
} [GbrKq(
public int getCountId(){ /
xv5we~
return countId; 1
K}gX>F
} ~Q=;L>Qd
} 97 SS0J
5@l5exuG*m
CountCache.java {$EX :ID
s2L]H
/* 5 v.&|[\k
* CountCache.java A'CD,R+gR
* 3]1 !g6
* Created on 2007年1月1日, 下午5:01 '?$@hqQn
* |?jgjn&RQ
* To change this template, choose Tools | Options and locate the template under `<>#;%
* the Source Creation and Management node. Right-click the template and choose }o]}R#|
* Open. You can then make changes to the template in the Source Editor. A)~oD_ooQ
*/ ;F1y!h67<
xppnBnu$7
package com.tot.count; +8ib928E
import java.util.*; \
o2oQ3
/** KPy)%i
* (@NILK
* @author ,>#\aO1n
*/ rbOJ;CK
public class CountCache { j8M t"B
public static LinkedList list=new LinkedList(); `~\SQ EY$
/** Creates a new instance of CountCache */ +h-% {
public CountCache() {} d>#',C#;
public static void add(CountBean cb){ fwUvFK1G
if(cb!=null){ .]exY
i
list.add(cb); kj|Oj+&
} v1i-O'
} F
]X<q uuL
} ;4-$C =&
>#n"r1
CountControl.java $-^&AKc
#3ZAMV
/* cL .z{
* CountThread.java i'CK/l.H
* YL`ML t4MC
* Created on 2007年1月1日, 下午4:57 D|U bh ]
* 'O 7:=l
* To change this template, choose Tools | Options and locate the template under v2rzHzFU
* the Source Creation and Management node. Right-click the template and choose 5f_x.~ymA
* Open. You can then make changes to the template in the Source Editor. q8ZxeMqx%
*/ _=x*yDPG}
]Ls T
package com.tot.count; :)Es]wA#HZ
import tot.db.DBUtils; WyV,(~y
import java.sql.*; z z]~IxQ
/** A]Hz?i
* R%LFFMVn
* @author &b~X&{3,
*/ cb'Ya_
public class CountControl{ s8:epcL`A
private static long lastExecuteTime=0;//上次更新时间 Msvs98LvW
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ai/]E6r
/** Creates a new instance of CountThread */ i+QVs_jW
public CountControl() {} 'N6oXE
public synchronized void executeUpdate(){ 7gLk~*
Connection conn=null; vC&0UNe$
PreparedStatement ps=null; I`xC0ZUKj
try{ [x?9<#T
conn = DBUtils.getConnection(); ":e6s co
conn.setAutoCommit(false); '/D2d
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 8|=
c3Z
for(int i=0;i<CountCache.list.size();i++){ ?.ObHV*k
CountBean cb=(CountBean)CountCache.list.getFirst(); \aof
CountCache.list.removeFirst(); m{>"
ps.setInt(1, cb.getCountId()); x| D|d}
ps.executeUpdate();⑴
|,KsJ2hD
//ps.addBatch();⑵ ('%Y3z;
} 8d1qRCIz
//int [] counts = ps.executeBatch();⑶ yL<u>S0
conn.commit(); hG`@#9|f
}catch(Exception e){ }'{"P#e8"q
e.printStackTrace(); X9c<g;
} finally{ 731RqUR
try{ j+fF$6po#t
if(ps!=null) { DB|w&tygq
ps.clearParameters(); 0gOca +&
ps.close(); O|Vc
ps=null; D\ZH1C!d
} f3vl=EA4|
}catch(SQLException e){} z+M{zr
DBUtils.closeConnection(conn); l`6.(6
} 5`}za-
} O)R}|
public long getLast(){ Y]~-S
return lastExecuteTime;
;j~%11
} +p _?ekV\
public void run(){ EBWM8~Nm#
long now = System.currentTimeMillis(); _8SB+s*
if ((now - lastExecuteTime) > executeSep) { {{bwmNv"
//System.out.print("lastExecuteTime:"+lastExecuteTime); H#X*OJ
//System.out.print(" now:"+now+"\n"); v:!TqfI
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 3GL?&(eU;
lastExecuteTime=now; Y$,++wx
executeUpdate(); k!z.6di
} g>7i2
else{ }/tf^@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2>.b~q@
} mo
tW7|p.e
} ZLVgK@l
} "7fEL:|j
//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 sm?b,T/
M4;M.zxJv
类写好了,下面是在JSP中如下调用。 F;/^5T3wI
fGH)Fgo`
<% #u"@q< )
CountBean cb=new CountBean(); FP y}Wc*UA
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 6]GHCyo
CountCache.add(cb); st.{AEv@
out.print(CountCache.list.size()+"<br>"); (-;(wCEE
CountControl c=new CountControl(); 2u0B=0x
c.run(); ETX>wZ
out.print(CountCache.list.size()+"<br>"); AL&<SxuP
%>