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: m=%W <8[V
Z.YsxbH3
CountBean.java TXrC5AJx
](8XC_-U'
/* Uv%"45&7
* CountData.java p8F|]6Z
* NPf,9c;
* Created on 2007年1月1日, 下午4:44 >@ EQarD
* _Zb_9&
* To change this template, choose Tools | Options and locate the template under '| Ag,x[
* the Source Creation and Management node. Right-click the template and choose sy>P n
* Open. You can then make changes to the template in the Source Editor. q$EVd9aN
*/ q8[Nr3.
xES+m/?KlZ
package com.tot.count; 6EPC$*Xp!
/md`tqI>i<
/** u6 B (f;
* Zc%S`zK`7
* @author urtcSq&H'
*/ CWC*bkd5a
public class CountBean { UbMcXH8=F
private String countType; xFyMg&
int countId; !q7M+j4
/** Creates a new instance of CountData */ li; P,kg$
public CountBean() {} )Hev-C"
public void setCountType(String countTypes){ IXzad
this.countType=countTypes; ,QKG$F
} $F/&/Aa
public void setCountId(int countIds){ QP\vN|r
this.countId=countIds; X)nOY*
} nq6]?ZJ
public String getCountType(){ lXB_HDY
return countType; Tri.>@-u
} L;BYPZR
public int getCountId(){ YW/<. 0rI
return countId; IM
+Dm
} VN$#y4
} @br%:Nt
L^ +0K}eD
CountCache.java sPd5f2'
gHox{*hb[
/* mZq*o<kTA
* CountCache.java =8tduB
* W^yF5
* Created on 2007年1月1日, 下午5:01 L`"cu.l
* OgOu$.
* To change this template, choose Tools | Options and locate the template under t^h>~o'\
* the Source Creation and Management node. Right-click the template and choose VfZ/SByh7p
* Open. You can then make changes to the template in the Source Editor. 2\s-4H|
q
*/ yn%w'
tX)]ZuEi$
package com.tot.count; QQrvT,]
import java.util.*; YY]LK%-
/** i]1[eGF
* )<3WVvB
* @author 3>S.wyMR4
*/ -Mv`|odY/
public class CountCache { 5[Q44$a{
public static LinkedList list=new LinkedList(); B}?/oZW4
/** Creates a new instance of CountCache */ &/7GhZRt
public CountCache() {} k+s<;{
public static void add(CountBean cb){ Mq*Sp
UR
if(cb!=null){
!N)oi$T%
list.add(cb); Qh{=Z^r
} gu"Agct4
} VvoJ85
} aC%0jJ<eo
2b3*zB*@V
CountControl.java *nH ?o* #
Zj}DlNkVu
/* |d,1mmv@K
* CountThread.java ^ro?.,c T
* S++}kR);
* Created on 2007年1月1日, 下午4:57 ZZeqOu7^
* u\Xi]pZ@X]
* To change this template, choose Tools | Options and locate the template under "M? (Ax
* the Source Creation and Management node. Right-click the template and choose NtA}I)'SWU
* Open. You can then make changes to the template in the Source Editor. lhxhAe
*/ sL!6-[N
rc;| ,\
package com.tot.count; @l@lE0
import tot.db.DBUtils; UO!OO&l!
import java.sql.*; AE<AEq
/** hl# 9a?
* nbOMtK
* @author &Nec(q<
*/ QDgOprha
public class CountControl{ _`;6'}]s
private static long lastExecuteTime=0;//上次更新时间 QY{f=
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 b [u_r,b
/** Creates a new instance of CountThread */ ,:,c
kul
public CountControl() {} ,q:6[~n
public synchronized void executeUpdate(){ : ;d&m
Connection conn=null; #s]]\
PreparedStatement ps=null; #}B~V3UD
try{ KIuYWr7&
conn = DBUtils.getConnection(); rW1>t+
conn.setAutoCommit(false); \!631FcQ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); :jUd?(
for(int i=0;i<CountCache.list.size();i++){ %n-LDn
CountBean cb=(CountBean)CountCache.list.getFirst(); yyiZV\ /
CountCache.list.removeFirst(); zlXkD~GV
ps.setInt(1, cb.getCountId()); 3z5,4ps
ps.executeUpdate();⑴ /,B"H@J
//ps.addBatch();⑵ 0dnm/'L
} no; Yu
//int [] counts = ps.executeBatch();⑶ 9|OQHy
conn.commit(); S :oZ&
}catch(Exception e){ P}aJvFlmP
e.printStackTrace(); T!/$@]%\7
} finally{ =fRP9`y
try{ H,\c"
if(ps!=null) { X}?cAo2N
ps.clearParameters(); op"Cc
ps.close(); AWf zMJ;VS
ps=null; SmtH2%y I
} MiRMjQ2
}catch(SQLException e){} ^ ]`<nO
DBUtils.closeConnection(conn); qdcCX:Z<
} d/* [t!
} x9@%L{*
public long getLast(){ (j cLzq
return lastExecuteTime; `@`Q"J
} |7f}icXKur
public void run(){ "e(OO/EZS
long now = System.currentTimeMillis(); ss-Be
if ((now - lastExecuteTime) > executeSep) { Q[g%((DL
//System.out.print("lastExecuteTime:"+lastExecuteTime); @gTpiV2
//System.out.print(" now:"+now+"\n"); ,Q}/#/
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 7OW;omT`
lastExecuteTime=now; N;ssO,
executeUpdate(); X|8Yz3:o
} w0Us8JNGz
else{ Gb8LW,$IT-
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); e[{LNM{/#
} C\}m_`MR
} ty7a&>G
} 4; j#7
//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 yqB{QFXO
op}x}Ioz
类写好了,下面是在JSP中如下调用。 KiCZEA
VQLo
vt"
<% =D3Y
q?
CountBean cb=new CountBean(); 3`="4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); g]d@X_ &D
CountCache.add(cb); I.\u2B/?
out.print(CountCache.list.size()+"<br>"); \yM[?/<
CountControl c=new CountControl(); o_={xrmIA
c.run(); qWr`cO~hc
out.print(CountCache.list.size()+"<br>"); dqG+hh^
%>