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: dP"cm0
@6-3D/=
CountBean.java =@nW;PUZ
G0Z$p6z
/* s !II}'Je
* CountData.java s"~,Zzy@j
* 4C3i
* Created on 2007年1月1日, 下午4:44 u,~+ho@
* ^ '_Fd
* To change this template, choose Tools | Options and locate the template under a(uQGyr[k1
* the Source Creation and Management node. Right-click the template and choose ?OGs+G
* Open. You can then make changes to the template in the Source Editor. IvI;Q0E-3
*/ Z/:W.*u
$4kbOqn4
package com.tot.count; ^P`I"T
d
<
B!f;
/** waG &3m
* DLO#_t^v.
* @author )i:"cyoE
*/ y,c\'}*H
public class CountBean { ZIc-^&`r=
private String countType; g^U-^f
int countId; ]SN5&S
/** Creates a new instance of CountData */ K3&k+~$
public CountBean() {} 8jiBLZkRf
public void setCountType(String countTypes){ k8cR`5@PK
this.countType=countTypes; 5nK|0vv%2
} 89W8cJ$yW
public void setCountId(int countIds){ h}}7_I9
this.countId=countIds; "o@R}_4]q
} -*2b/=$u
public String getCountType(){ 3Qp6$m
return countType; c~6ywuq+M`
} {@s6ly].
public int getCountId(){ $>Gf;k
return countId; [3qJUJM
} >f;oY9 {m
} lxBcO/
|r4&@)
CountCache.java [mF=<G"
{@Z*.G^
/* $$R->
* CountCache.java 8:]5H}Hi
* lg@q}
]1
* Created on 2007年1月1日, 下午5:01 5^Lbc.h
* Q?'Ax"$D
* To change this template, choose Tools | Options and locate the template under bf[l4$3k
* the Source Creation and Management node. Right-click the template and choose MN>U jFA
* Open. You can then make changes to the template in the Source Editor. rWBgYh
*/ $<f+CtD4
ePxf.U
package com.tot.count; zj=F4]w
import java.util.*; 'NnmLM(oh
/** T n,Ifo3
* C%P.`Nx A
* @author 7f~7vydZ}
*/ MF$NcU
public class CountCache { P[e#j
public static LinkedList list=new LinkedList(); 5=!aq\
5
/** Creates a new instance of CountCache */ `$/M\aM%
public CountCache() {} u;8bbv4
public static void add(CountBean cb){ U*T :p>&
if(cb!=null){ Kn\$\?u
list.add(cb); ,- _ReL
} J^Wqa$<;"
} OW8TiM
mK
} ; d}
;bq
EfV0`2
CountControl.java |G)bnmi7
;=8@@9
/* &<C&(g{Z
* CountThread.java uJ,I6P~9
* WW~QK2o-@
* Created on 2007年1月1日, 下午4:57 b~K-mjJI
* ET3+07
* To change this template, choose Tools | Options and locate the template under KpO%)M!/Z#
* the Source Creation and Management node. Right-click the template and choose mPi{:
* Open. You can then make changes to the template in the Source Editor. eBW]hwhKzM
*/ `=8G?3
U9R pHh`
package com.tot.count; ~ o5h}OU"
import tot.db.DBUtils; `]<~lf
import java.sql.*; );^{;fLy%
/** ralU9MN.
* hPUYq7B
* @author 3[To"You
*/ &MP8.(u `
public class CountControl{ ~I%JVX%
private static long lastExecuteTime=0;//上次更新时间 }iR!uhi#
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 H3S u'3
/** Creates a new instance of CountThread */ *Rj*%S
public CountControl() {} a#,lf9M
public synchronized void executeUpdate(){ 3.
g-V
Connection conn=null; H, O_l%
PreparedStatement ps=null; pB,@<\l %
try{ ' :,p6
conn = DBUtils.getConnection(); 3a,7lTUuB
conn.setAutoCommit(false); hfQ^C6yR
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); wW^3/
for(int i=0;i<CountCache.list.size();i++){ .fS1
CountBean cb=(CountBean)CountCache.list.getFirst(); Lmyw[s\U
CountCache.list.removeFirst(); 6z+*H7Qz
ps.setInt(1, cb.getCountId()); No)@#^
ps.executeUpdate();⑴ f@IL2DL}\
//ps.addBatch();⑵ $ZE"o`=7
} :*lB86Ly
//int [] counts = ps.executeBatch();⑶ -Cf<
#'x_
conn.commit(); YZ+<+`Mz<
}catch(Exception e){ rjT!S1Hs
e.printStackTrace(); 4_?*@L1
} finally{ j'FBt8P'
try{ skfFj&_T
if(ps!=null) { )TgjaR9G
ps.clearParameters(); ZlYb8+rW
ps.close(); 3)qtz_,H/g
ps=null; <}Rr C#uiA
} ed7Hz#Qc
}catch(SQLException e){} -"3<Ll
DBUtils.closeConnection(conn); N/mC,7Q
} A*hc
w
} {-\VX2:;[9
public long getLast(){ 2<5s0GT'/
return lastExecuteTime; NU|T`gP
} "@E(}z'sM
public void run(){ =nN&8vRH
long now = System.currentTimeMillis(); |70Lh+
if ((now - lastExecuteTime) > executeSep) { v\ Xk6k
//System.out.print("lastExecuteTime:"+lastExecuteTime); <lVW;l7
//System.out.print(" now:"+now+"\n"); i6h , Aw3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); E@\bFy_!>b
lastExecuteTime=now; ]#x?[F
executeUpdate(); B(dq$+4
} *Z"(K\1TH
else{ !/MHD
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); m.N/g,
} 0sKY;(
} Z"G@I= Q(
} KA$l.6&d
//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 NFcMh+qnK
Y vjRJ
类写好了,下面是在JSP中如下调用。 bi[gyl#
lTpmoDa%
<% ~*h` ?A0
CountBean cb=new CountBean(); h+h`0(z
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); iw^(3FcP@C
CountCache.add(cb); bPtbU:G
out.print(CountCache.list.size()+"<br>"); $ OMGo`z
CountControl c=new CountControl(); co!#.
c.run(); ByPzA\;e
out.print(CountCache.list.size()+"<br>"); &U8W(NxN
%>