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: ,a gc
4#ug]X4Y')
CountBean.java 8)O[Aq::
c\iA89msp
/* =; ^%(%Y{m
* CountData.java gXYI\.
* T.@aep\"
* Created on 2007年1月1日, 下午4:44 WX=Jl<
* '$|[R98
* To change this template, choose Tools | Options and locate the template under *+-}P|S:
* the Source Creation and Management node. Right-click the template and choose X *&[u7No
* Open. You can then make changes to the template in the Source Editor. E_k$W5
*/ 'SCidN(n
~Q?a|mV,
package com.tot.count; WOQP$D9
K <pV
/** hCCiD9gz
* }2(,K[?
* @author JQV%fTH S
*/ LA@w:Fg
public class CountBean { "]z-: \ V
private String countType; <%maDM^_\(
int countId; 1abtgDL
/** Creates a new instance of CountData */ h(M#f7'~&
public CountBean() {} cc#gEm)3C
public void setCountType(String countTypes){ .#1~Rz1r
this.countType=countTypes; 9A}# 6
} 0/!dUWdKH
public void setCountId(int countIds){ 6,d@p
this.countId=countIds; 2Tfz=7h$
} *$p2*%7Ne
public String getCountType(){ 7bk%mQk
return countType; u:[vaBh91
} V\u>"3BQw
public int getCountId(){ MO&}r7qq
return countId; h v8P4"i v
} %%NlTE8*
} -sw
.
\<y`!"c
CountCache.java Fe]B&n
W.dt:_
/* Rn{iaM2Y<
* CountCache.java : y5<go8e
* kBYNf =
* Created on 2007年1月1日, 下午5:01 Hj:r[/
* oN{Z+T :
* To change this template, choose Tools | Options and locate the template under L1ieaKw
* the Source Creation and Management node. Right-click the template and choose lmfi
* Open. You can then make changes to the template in the Source Editor. I3,= 0z
*/ !OA]s%u
;\lW5ZX
package com.tot.count; et,f_fd7v
import java.util.*; sYjpU
/** O>^C4c!
* {)
Q@c)'
* @author R,F[XI+=N
*/ q>mE<
(-M
public class CountCache {
0BH_'ZW
public static LinkedList list=new LinkedList(); KcK>%%
/** Creates a new instance of CountCache */ VwOW=4`6
public CountCache() {} Svc|0Ad&
public static void add(CountBean cb){ SILQ
if(cb!=null){ c3:,Ab|
list.add(cb); UVw~8o9s
} PNaay:a|
} BO~PT,QrF
} EX?MA6U
^1Zeb$Nw'
CountControl.java
/o[?D
wQwQXNG
/* 6`v7c!7
* CountThread.java \RvvHty-V
* jFA{+Yr1
* Created on 2007年1月1日, 下午4:57
"Qja1TQ
* CAcS~ "
* To change this template, choose Tools | Options and locate the template under "\}@gV#r$A
* the Source Creation and Management node. Right-click the template and choose xER\ZpA:,
* Open. You can then make changes to the template in the Source Editor. rb1`UG"h$
*/ >TQH|}|6(y
+m8!U=Zi
package com.tot.count; ))&;}2{
import tot.db.DBUtils; m|=H#
import java.sql.*; q{t*34R
/** NX|v=
* [k6nW:C
* @author d/bEt&
*/ mnmP<<8C,
public class CountControl{ =$nB/K,8AX
private static long lastExecuteTime=0;//上次更新时间 h"_~7jq"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AwslWkd=
/** Creates a new instance of CountThread */ \/1<E?Q
f
public CountControl() {} Td G!&:>
public synchronized void executeUpdate(){ /c2w/+ _
Connection conn=null; d4nH_?
PreparedStatement ps=null; L
]w/P|
try{ GDD '[;
conn = DBUtils.getConnection(); .h9l7
nZt
conn.setAutoCommit(false); " )V130<
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); b|+wc6
for(int i=0;i<CountCache.list.size();i++){ 2Z3('?\z~
CountBean cb=(CountBean)CountCache.list.getFirst(); U2`'qsR1
CountCache.list.removeFirst(); S(uf(q|{
ps.setInt(1, cb.getCountId()); 'UMXq~RMe
ps.executeUpdate();⑴ wg0 \_@3
//ps.addBatch();⑵ rMU T_^
} xfb]b2
//int [] counts = ps.executeBatch();⑶ 4dhvFGlW
conn.commit(); `67[O4$<
}catch(Exception e){ 6IWxPt~
e.printStackTrace(); {%IE xPJ
} finally{ r=6v`)Qr
try{ /)dFK~
if(ps!=null) { >2]JXLq
ps.clearParameters(); 'A:x/iv}^
ps.close(); DqX{'jj
ps=null; [o.B
} 3bDQk
:L
}catch(SQLException e){} Fd#m<"
DBUtils.closeConnection(conn); oI.G-ChP
} l'\pk<V
} lKlU-4
public long getLast(){ PSPmO'C+
return lastExecuteTime; wlEdt1G
} \[jq4`\$
public void run(){ D5:{fWVsV/
long now = System.currentTimeMillis(); 7}vg.hmZ
if ((now - lastExecuteTime) > executeSep) { @DZB9DDR
//System.out.print("lastExecuteTime:"+lastExecuteTime); CT1ja.\;
//System.out.print(" now:"+now+"\n"); 2AtLyN'.
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6%fKuMpK(
lastExecuteTime=now; (4\d]*u5-c
executeUpdate(); [-)r5Dsdq
} i} N8(B(
else{ Z7RiPSdxp
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); m+#iR}*1L
} 1P(|[W1
} ,}:G\u*Fu
} wbe<'/X+
//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 2 ho>eRX
)=-0M9e.{
类写好了,下面是在JSP中如下调用。 6<$Odd
Vo7dAHHL
<% %s&ChM?8F
CountBean cb=new CountBean(); >P/][MT
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); xY$iz)^0&
CountCache.add(cb); Y}[ c^$S
out.print(CountCache.list.size()+"<br>"); <}sq?Sfq!
CountControl c=new CountControl(); ;>AL`M+
c.run(); 6<' 21
out.print(CountCache.list.size()+"<br>"); HgBGV0
%>