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: =k!F`H`/%'
8rz,MsFR
CountBean.java @Js@\)P79
ufA0H
J)Yg
/* 7Z81+I|&8
* CountData.java G1,u{d-_
* |;C;d"JC2
* Created on 2007年1月1日, 下午4:44 THwq~c'
* PXDJ[Oj7(0
* To change this template, choose Tools | Options and locate the template under ,;=is.h9
* the Source Creation and Management node. Right-click the template and choose <z
wI@i
* Open. You can then make changes to the template in the Source Editor.
<j_
*/ gX5.u9%C\
[s-!tE3-
package com.tot.count; {]y!2r
#vcQ =%;O
/** SR/
"{\C
* s*>B"#En
* @author DK%@[D
*/ bde6
;=oM
public class CountBean { Y$ZDJNz
private String countType; m?1AgsBR
int countId; uKT\\1Jrq
/** Creates a new instance of CountData */ {~=gKZ:-@
public CountBean() {} D rouEm
public void setCountType(String countTypes){ yyjgPbLN=
this.countType=countTypes; 61z^(F$@
} z8PV&o
public void setCountId(int countIds){ W%#LHluP
this.countId=countIds; M;0\fUh;
} ':T"nORC
public String getCountType(){ ?=Mg"QU
return countType; M[=sQnnSFW
} G^\.xk]
public int getCountId(){ fd1z
XK#Z2
return countId; ;q2e[ y
} n{%[G2.A
} d]l(B+\vf
!R$t>X
CountCache.java 3.04Toq!
[sG!|@r
/* HD}3mP
* CountCache.java cvnRd.&
* ^0"[l {
* Created on 2007年1月1日, 下午5:01 Zu^J X/um
* EMS$?"K
* To change this template, choose Tools | Options and locate the template under Y&*nj`n
* the Source Creation and Management node. Right-click the template and choose `H|#l\
* Open. You can then make changes to the template in the Source Editor. [PU0!W;
*/ 'A#l$pJp7
#_fL[j&
package com.tot.count; ,09d"7`X
import java.util.*; =Wl}Pgo!
/** fh}j)*K8
* |uln<nM9
* @author izP>w*/nO
*/ qH*Fv:qnM
public class CountCache { ^:m7Qd?Z[
public static LinkedList list=new LinkedList(); \;Q:a
/ur9
/** Creates a new instance of CountCache */ #mc GT\tQ
public CountCache() {} q6N6QI8/
public static void add(CountBean cb){ 'Y-Y
By :
if(cb!=null){ 2NqO,B|R
list.add(cb); pGSS
} Y[alOJ
} ~@ hiLW
} }tH6E
GMoE,L
CountControl.java Nc[u?-
:+}Eo9
/* Jg%jmI;Y
* CountThread.java kT4Tb%7KM
* ;PX>] r5U0
* Created on 2007年1月1日, 下午4:57 lhx]r}@'MC
* A{QA0X!p
* To change this template, choose Tools | Options and locate the template under gLPgh%B4
* the Source Creation and Management node. Right-click the template and choose s4{ >7`N2
* Open. You can then make changes to the template in the Source Editor. +,ojlTVlt
*/ vBjrI*0
wO ?A/s
package com.tot.count; ,qO2D_
import tot.db.DBUtils; ^
Nm!b
import java.sql.*; r4Jc9Tvd
/** Y**|e4
* +`~6Weay
* @author y8=H+Y
*/ *Nh[T-y(s
public class CountControl{ -85W/%
private static long lastExecuteTime=0;//上次更新时间 xsdi\
j;n>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 +HNM$yp
/** Creates a new instance of CountThread */ $n@B:kv5p
public CountControl() {} L)j<;{J/Q0
public synchronized void executeUpdate(){ MFm2p?zPm
Connection conn=null; <ULydBom
PreparedStatement ps=null;
:Z5Twb3h
try{ ^N:bT;;$nZ
conn = DBUtils.getConnection(); Q !G^CG
conn.setAutoCommit(false); 6'1m3<G_
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); nf9NJ_8}4H
for(int i=0;i<CountCache.list.size();i++){ 16R0#Q/{+*
CountBean cb=(CountBean)CountCache.list.getFirst(); V'&`JZK6
CountCache.list.removeFirst(); ww$Ec
ps.setInt(1, cb.getCountId()); ua>YI
ps.executeUpdate();⑴ \J,pV
//ps.addBatch();⑵ H^C$2 f
} &S+ooj
//int [] counts = ps.executeBatch();⑶ Ow4H7sl
conn.commit(); ^26}j uQ
}catch(Exception e){ t bEJyA
e.printStackTrace(); %6@->c{
} finally{ JP*VR=0k?
try{ dw]jF=u
if(ps!=null) { ._IBO; *@
ps.clearParameters(); hTVA^j(w
ps.close(); r;cILS|Xr
ps=null; 79O'S du@
} j$Z:S~*
}catch(SQLException e){} `5CuH
DBUtils.closeConnection(conn); Tg~SGAc
} |#?:KvU97E
} #J09Eka;J
public long getLast(){ U[t/40W}P
return lastExecuteTime; xb~8uD5
} |Y&&g=7
public void run(){ j0+l-]F-
long now = System.currentTimeMillis(); E|v9khN(].
if ((now - lastExecuteTime) > executeSep) { #:LI,t
//System.out.print("lastExecuteTime:"+lastExecuteTime);
d|
OEZx
//System.out.print(" now:"+now+"\n"); %d"d<pvx
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); C6{\^kG^j2
lastExecuteTime=now; 5>u,Qh
executeUpdate(); )7s(]~z
} U/l3C(bc!
else{ %$CV?K$C
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 's_[#a;Vp
} @ UCr`>
} ;fGh]i
} '$\O*e'
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Vx*O^cM
].r~?9'/
类写好了,下面是在JSP中如下调用。 {IA3`y~
::R5F4
<% \qj(`0HG
CountBean cb=new CountBean(); SM8Wg>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0S71&I$u]
CountCache.add(cb); ~duF2m 72
out.print(CountCache.list.size()+"<br>"); !rZ r:@
CountControl c=new CountControl(); {~cM 6W]f
c.run(); :ExCGS[
out.print(CountCache.list.size()+"<br>"); NY3.?@Z
%>