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: .4^+q9M
;Va(l$zD
CountBean.java 5NZuaN
%]}JWXof
/* C33Jzn's
* CountData.java r1< 'l
* kMCP .D45;
* Created on 2007年1月1日, 下午4:44 pF8$83S
* _y[C52,
* To change this template, choose Tools | Options and locate the template under 9Of;8R
* the Source Creation and Management node. Right-click the template and choose 1"Oe*@`pV
* Open. You can then make changes to the template in the Source Editor. SX"|~Pi(
*/ n#x_da-m]
9JP:wE~y
package com.tot.count; x
t-s"A
y\^zxG*]'
/** K9EHT-
* *fc8M(]&d
* @author 1ARtFR2C{b
*/ qI9j=4s.
public class CountBean { ;SU<T^a
private String countType; ;)FvTm'"\.
int countId; 8_!qoW@B
/** Creates a new instance of CountData */ 5%\K
public CountBean() {} h@R n)D
public void setCountType(String countTypes){ +:@^nPfHy
this.countType=countTypes; M,JwoKyg
} N9 M}H#
public void setCountId(int countIds){ P1[.[q/-e
this.countId=countIds; DGGySO6=$e
} 5go)D+6s
public String getCountType(){ I[&x-}w
return countType; 8(4!x$,Z5
} |iUF3s|?
public int getCountId(){ 9ia&/BT7"z
return countId; [8za=B/
} kEq~M10
} 2?%*UxcO
.\oW@2,RA9
CountCache.java V]--d33/a
U>*@VOgB
/* I*TTD]e'X
* CountCache.java \m|5Aqs
* vxPE=!|
* Created on 2007年1月1日, 下午5:01 ?VotIruR
* /E<Q_/'Z
* To change this template, choose Tools | Options and locate the template under 9e`};DE
* the Source Creation and Management node. Right-click the template and choose ,]0BmlD
* Open. You can then make changes to the template in the Source Editor. d3rjj4N"z
*/ aU;X&g+_)
_UTN4z2aTG
package com.tot.count;
dHx4yFS
import java.util.*; [xM&Jdf8
/** ,M`1 k
* #9(+)~irz`
* @author {D8opepO)
*/ |Jx:#OM
public class CountCache { 25Z}.))
public static LinkedList list=new LinkedList(); W]Xwt'ABz
/** Creates a new instance of CountCache */ %R4 \[e
public CountCache() {} DtBvfYO8)>
public static void add(CountBean cb){ HR?T
if(cb!=null){ OiAuL:D
list.add(cb); !q$VnqFk
} &w^9#L
} vGsAM*vw6
} eMdP4<u
Os[z>H?
CountControl.java m<j;f
3L==p`
/* ?wkT=mv
* CountThread.java ILDO/>n
* &V
axv$v}
* Created on 2007年1月1日, 下午4:57 !j7mY9x+
* p,z>:3M
* To change this template, choose Tools | Options and locate the template under uzQj+Po
* the Source Creation and Management node. Right-click the template and choose VOj7Tz9UD
* Open. You can then make changes to the template in the Source Editor. 5GAW3j{
*/
P'B|s/)
bJPKe]spJ=
package com.tot.count; r Yt|[Pk
import tot.db.DBUtils; kO`!!M[Oo
import java.sql.*; v @M6D}
/** }~LGq.H
* N}/V2K]Q
* @author lPz`?Hn
*/ ]lKUpsQI
public class CountControl{ pvsY
0a@4
private static long lastExecuteTime=0;//上次更新时间 L %ac sb}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 =),ZZD#J
/** Creates a new instance of CountThread */ nnhI]#,a{
public CountControl() {} Y*9vR~#H
public synchronized void executeUpdate(){ 3>3t(M|
Connection conn=null; rhOxyY0
PreparedStatement ps=null; =g6~2p=H
try{ yD\Kn{
conn = DBUtils.getConnection(); &^&0,g?To
conn.setAutoCommit(false); p&\QkI=
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); l@w\
Vxr
for(int i=0;i<CountCache.list.size();i++){ ?r|iZKa
CountBean cb=(CountBean)CountCache.list.getFirst(); U&(gNuR>J
CountCache.list.removeFirst(); :s+?"'DP
ps.setInt(1, cb.getCountId()); k {{eyC
ps.executeUpdate();⑴ 93Gj#Mk
//ps.addBatch();⑵ IIMf\JdM
} < (9
BO &
//int [] counts = ps.executeBatch();⑶ 'S}3lsIE
conn.commit(); hB<(~L?A]
}catch(Exception e){ ghW`xm87
e.printStackTrace(); _)pOkS
} finally{ +Goh`!$Rj9
try{ |#t^D.j
if(ps!=null) { !ck luj
ps.clearParameters(); 4J'0k<5S
ps.close(); (ZF~
ps=null; 3`D*AFQc
} _~1O #*|4
}catch(SQLException e){} Jon3ywd1Y
DBUtils.closeConnection(conn); EpACd8Fb
} $[HCetaqV
} Y[b08{/
public long getLast(){ xv>8rW(Np5
return lastExecuteTime; P;XA|`&
} kn$SG
public void run(){ Ot=nKdP}D
long now = System.currentTimeMillis(); 1M)88&
if ((now - lastExecuteTime) > executeSep) { )X *_oH=
//System.out.print("lastExecuteTime:"+lastExecuteTime); f[NxqNn
//System.out.print(" now:"+now+"\n"); G?~Yw'R^8
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); #Q_Scxf
lastExecuteTime=now; rUV'DC?eE
executeUpdate(); Qg1kF^=
} Iw] ylp
else{ =saRh)EM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); fZap\
} =j w?*
} d+h~4'ebv
} +`S_Gy
//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 GRj [2I7:
]n1#8T&<*z
类写好了,下面是在JSP中如下调用。 3&[ d.,/
_W Hi<,-
<% ;O>zA]Z8r
CountBean cb=new CountBean(); V@z/%=PJ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9.
FXbNYg
CountCache.add(cb); (O:&RAkk7
out.print(CountCache.list.size()+"<br>"); v8\_6}*I
CountControl c=new CountControl(); | LZ+_
c.run(); G a$2o6
out.print(CountCache.list.size()+"<br>"); .pxUO3g
%>