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: PN^1
_:=OHURc
CountBean.java <:;:*s3]
twHM~cTS
/* ~S=fMv^BR
* CountData.java [@)z $W
* H"RF[bX(
* Created on 2007年1月1日, 下午4:44 `:BQ&T%UQR
* ?eVuz x
* To change this template, choose Tools | Options and locate the template under k-DB~-L
* the Source Creation and Management node. Right-click the template and choose `# M.t);^
* Open. You can then make changes to the template in the Source Editor. U*fj5
*/ }!7DF
k$x
'v#
package com.tot.count; K\E]X\:
4C9"Q,o%&
/** :8|3V~%m
* *Qwhi&k
* @author 79B`w
#
*/ |`;1p@w"
public class CountBean { (xSi6EZ6;
private String countType; 8qYGlew,
int countId; %b%<g%@i
/** Creates a new instance of CountData */ f`]E]5?
public CountBean() {} mhkAI@)>
public void setCountType(String countTypes){ dVtLYx
this.countType=countTypes; qjEWk."
} k+GK1Yl
public void setCountId(int countIds){ 2#A9D.- h
this.countId=countIds; *7fPp8k+Z;
} [W\atmd"
public String getCountType(){ (Rg!km%2T
return countType; 2gR_1*|
} ~rJw$v
public int getCountId(){ 1;~ 1U9V
return countId; M j%|'dZz
} MG5Sn*(C
} OO+#KyU
j72]_G
CountCache.java +P)[|y +e
nV xMo_
/* ^8*SCM_A
* CountCache.java J8?6G&0H
* 'xXqEwi4
* Created on 2007年1月1日, 下午5:01 M "P
* Y+`-~ 88
* To change this template, choose Tools | Options and locate the template under BRzWZq%r3
* the Source Creation and Management node. Right-click the template and choose ggsi`Z{j?
* Open. You can then make changes to the template in the Source Editor. rxI&;F#
*/ tBI+uu aa2
s=Q*|
package com.tot.count; X*yp=qI
import java.util.*; HYnq x>L ~
/** +rpd0s49
* (tLQX~Ur
* @author [qMO7enu#
*/ 8=o5;]Cg
public class CountCache { [QN7+#K,
public static LinkedList list=new LinkedList(); eh/OCzWH
/** Creates a new instance of CountCache */ ]S aH/$
public CountCache() {} k3.p@8@:
public static void add(CountBean cb){ T9<nD"=:
if(cb!=null){ Zy3&Zt
list.add(cb); j!o3g;j
} "LIii1]k
} y-q?pqt
} o9d$
4s@/
s /q5o@b{
CountControl.java s@[t5R
U7%pOpO!
/* +4nR&1z$
* CountThread.java .EZ{d
* f\r4[gU@
* Created on 2007年1月1日, 下午4:57 Zt0%E<C{
* vFC=qLz:
* To change this template, choose Tools | Options and locate the template under M`fXH 3D
* the Source Creation and Management node. Right-click the template and choose /lQ0`^yB
* Open. You can then make changes to the template in the Source Editor. v/+}FS=
*/ (Tb0PzA
|ylTy B
package com.tot.count; m`q>_*
import tot.db.DBUtils; \.|A,G=
import java.sql.*; UKQ&TV}0
/** 2.2a2.I1
* ?q }wl\"8
* @author 3Wxtxk._E
*/ :bDn.`KG#
public class CountControl{ ^J~4~!
private static long lastExecuteTime=0;//上次更新时间 m$qC
8z]
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 A1}+j-D7!y
/** Creates a new instance of CountThread */ .FRF<_`^
public CountControl() {} fqs p1m$
public synchronized void executeUpdate(){ J15T!_AW<
Connection conn=null; PR6uw
PreparedStatement ps=null; "UnSZ[;t
try{ .ehvhMuG|
conn = DBUtils.getConnection(); Vy~$%H94
conn.setAutoCommit(false); fQ4$@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); <7]
Y\{+
for(int i=0;i<CountCache.list.size();i++){ ioCkPj
CountBean cb=(CountBean)CountCache.list.getFirst(); B2WX#/lgd
CountCache.list.removeFirst(); rh&Eu qE%
ps.setInt(1, cb.getCountId()); L;7mt
4H
ps.executeUpdate();⑴ nKkTnTSa
//ps.addBatch();⑵ Z M, ^R?e
} iB`]Z@ZC
//int [] counts = ps.executeBatch();⑶ ?yeC
j1X
conn.commit(); TN aff
}catch(Exception e){ eaP$/U
D?
e.printStackTrace(); gc[J.[
} finally{ uCS
try{ B4&pBiG&f6
if(ps!=null) { ;*H~Yb0
ps.clearParameters(); )'|W[Sh?
ps.close(); %GiO1:t
ps=null; ua-|4@YO
} |o)
_=Fx
}catch(SQLException e){} tKGsrgoV
DBUtils.closeConnection(conn); E9-'!I !
} $KHDS:&
} IjAity.Xrq
public long getLast(){ zNJyF;3
return lastExecuteTime; }AYSQ~:
} =Fl4tY#X
public void run(){ 5B/\vLHg4
long now = System.currentTimeMillis(); FY*0gp
if ((now - lastExecuteTime) > executeSep) { Jo+C!kc
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7N=VVD~!b
//System.out.print(" now:"+now+"\n"); Nj8)HR
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 'p]qN;`'O$
lastExecuteTime=now; 0\*<k`dY
executeUpdate(); %$?Q%
} ]%hI-
else{ vUeel%
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); xTm&`Xo
} gg_(%.>
} x[6Bc
} N6%q%7F.:
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 bkI A:2HX
/2cOZ1G;
类写好了,下面是在JSP中如下调用。 L-gF$it\*b
E|3aiC,5
<%
(9|K}IM:
CountBean cb=new CountBean(); ^IkMRlJh%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); h1)\.F4G
CountCache.add(cb); yo6IY
out.print(CountCache.list.size()+"<br>"); 7}.(EZ0
CountControl c=new CountControl(); Av]N.HB$
c.run(); 7z&u92dJI
out.print(CountCache.list.size()+"<br>"); `" Pd$jW
%>