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: w?Cho</Xu
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CountBean.java >X=V Ph8
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/* 7 ;2>kgf~
* CountData.java $6 4{Ff
* 0w vAtK|Q
* Created on 2007年1月1日, 下午4:44 *&V"x=ba,
* cyh;1Q
* To change this template, choose Tools | Options and locate the template under Z&7Yl(|
* the Source Creation and Management node. Right-click the template and choose !Fs<r)j
* Open. You can then make changes to the template in the Source Editor. ,8cVv->u/
*/ Y@ vC!C
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package com.tot.count; ,F+,A].wG
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/** j9-.bGtm?.
* BA8!NR|
* @author =F5zU5`i
*/ Tr;&bX5]H
public class CountBean { 7g%\+%F
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private String countType; nHU}OGzW
int countId; -<e_^
/** Creates a new instance of CountData */ /"^XrVi-
public CountBean() {} +k0UVZZX?
public void setCountType(String countTypes){ ?30pNF|
this.countType=countTypes; ,D&-.`'E
} D z[,;
public void setCountId(int countIds){ Ylgr]?Db*
this.countId=countIds; j+>N&.zs
} .B'ws/%5\
public String getCountType(){ m/< @Qw
return countType; lsgZ
} z f>(Y7M
public int getCountId(){ o|_9%o52'
return countId; _BvGEM`o
} $bN_0s0:'
} IGlM}
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CountCache.java EoS6t
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/* 5,\|XQA5!
* CountCache.java PWO5R]
* Q9Go}}n
* Created on 2007年1月1日, 下午5:01 m6Qm }""
* Z|A+\#'
* To change this template, choose Tools | Options and locate the template under M<Y{Cs
* the Source Creation and Management node. Right-click the template and choose p<y\^a
* Open. You can then make changes to the template in the Source Editor. RcZ&/MY
*/ g!z &lQnZ
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package com.tot.count; pIKfTkSqH
import java.util.*; E
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/** >4Qj+ou
* Nk1p)V SC
* @author PO|gM8E1x?
*/ cE?p~fq<
public class CountCache { r[#*..Y
public static LinkedList list=new LinkedList(); ?KE:KV[Y
/** Creates a new instance of CountCache */ @ 0/EKWF
public CountCache() {} GC(QV}9z"
public static void add(CountBean cb){ sHOBT,B
if(cb!=null){ "s@q(J
list.add(cb); ;{0%Vp{
} 8?w#=@ s
} "#h/sAIs
} `1#Z9&bO
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CountControl.java o
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/* $2a_!/
* CountThread.java 6zGeGW
* ]H<}6}Gd
* Created on 2007年1月1日, 下午4:57 V|/N-3M
* ?.c:k;j
* To change this template, choose Tools | Options and locate the template under 6w_TL<S
* the Source Creation and Management node. Right-click the template and choose =%B}8$.|
* Open. You can then make changes to the template in the Source Editor. *o<|^,R
*/ Cn_r?1{W
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package com.tot.count; 2;w> w#}>
import tot.db.DBUtils; iT+t
import java.sql.*; AdzdYZiM_
/** s=Kz9WLy
* &3itBQF
* @author E#cu}zi
*/ Bp4#"y2
public class CountControl{ S$a.8Xh
private static long lastExecuteTime=0;//上次更新时间 ET%F+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 R''2o_F6
/** Creates a new instance of CountThread */ )r(e\_n
public CountControl() {} s~c cx"HH
public synchronized void executeUpdate(){ KbH|'/w
Connection conn=null; 8k_hX^
PreparedStatement ps=null; Un&rP70
try{ Dw,LB>Eq,
conn = DBUtils.getConnection(); n>)h9q S
conn.setAutoCommit(false); v7f[$s$m
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); hb>uHUb&
for(int i=0;i<CountCache.list.size();i++){ m]}EVa_I`/
CountBean cb=(CountBean)CountCache.list.getFirst(); pezfB{x?
CountCache.list.removeFirst(); {J/+KK
ps.setInt(1, cb.getCountId()); 7'ws: #pC
ps.executeUpdate();⑴ 7UUu1"|a|
//ps.addBatch();⑵ \vuWypo
} .s|5AC[
//int [] counts = ps.executeBatch();⑶ q77Iq0VR
conn.commit(); Pu'lp
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}catch(Exception e){ 6H0aHCM
e.printStackTrace(); V8Z@y&ny
} finally{ ZbH_h]1$D
try{ j_b/66JyN
if(ps!=null) { Zj0h0Vt
ps.clearParameters(); 7>EMr}f C
ps.close(); rAD4}A_w
ps=null; ('.I)n
} g9IIC5
}catch(SQLException e){} jPg[LZQ'
DBUtils.closeConnection(conn); J@J`)
} }Q-Tw,j
} c57`mOe/b
public long getLast(){ xX8c>p
return lastExecuteTime; @2>ce2+
} ]#r Nz"
public void run(){ ^GiWU +`
long now = System.currentTimeMillis(); 'G`xD3 E3,
if ((now - lastExecuteTime) > executeSep) { yz)Nco]
//System.out.print("lastExecuteTime:"+lastExecuteTime); ler$HA%F]
//System.out.print(" now:"+now+"\n"); W~s:SN
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); dE3M
lastExecuteTime=now; y4H/CH$%
executeUpdate(); upq3)t_
} T`c:16I
else{ 8 v da"
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2Ic)]6z
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} 'yh)6mid
} +u
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} %iZ~RTY6 !
//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 qr~zTBT]
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类写好了,下面是在JSP中如下调用。 gmOP8.g
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<% <W*6=HZ'
CountBean cb=new CountBean(); C k/DV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); WJ\,Y} J
CountCache.add(cb); 52r\Q}v$
out.print(CountCache.list.size()+"<br>"); \8k4v#wH
CountControl c=new CountControl(); C]3^:b+
c.run(); 5{-54mwo
out.print(CountCache.list.size()+"<br>"); &0+Ba[Z ^
%>