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: 9+1{a.JO
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CountBean.java {>ba7-Cy+y
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/* R{@saa5I(>
* CountData.java UdO8KD#r3
* SP%X@~d
* Created on 2007年1月1日, 下午4:44 AIHH@z
* [PIMG2"G
* To change this template, choose Tools | Options and locate the template under i<ES/U\
* the Source Creation and Management node. Right-click the template and choose UPfE\KN+p#
* Open. You can then make changes to the template in the Source Editor. M}|(:o3Yo
*/ 07.p
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package com.tot.count; 2y!n c%
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/** e)e(f"t6Q
* qR@ESJ_
* @author TZgtu+&
*/ E^-c,4'F
public class CountBean { "uBnK!
private String countType; Oa/^A-'Q
int countId; +p\E%<uQ
/** Creates a new instance of CountData */ ;?Pz0,{h
public CountBean() {} >|SIqB<%:
public void setCountType(String countTypes){ -m`|S q
this.countType=countTypes; Km5_P##
} 8>C4w 5kF
public void setCountId(int countIds){ H9T~7e+
this.countId=countIds; v^&HZk=(
} #ZZe*B!s_
public String getCountType(){ =IL\T8y09
return countType; 1GN^uia7
} [Hx}#Kds
public int getCountId(){ !RKuEg4hQ
return countId; u#ya
8
} gT8(LDJ
} MD[hqshoh
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CountCache.java gN/!w:
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/* /O[6PG
* CountCache.java 2c Xae
* VN)WBv
* Created on 2007年1月1日, 下午5:01 oCCtjr
* ROkwjw
* To change this template, choose Tools | Options and locate the template under qJ;~ANwt
* the Source Creation and Management node. Right-click the template and choose sV"tN2W@
* Open. You can then make changes to the template in the Source Editor. %wbdg&^
*/ u(Mbp$R'?
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package com.tot.count; }%XB*pzQ
import java.util.*; \6
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/** L\4rvZa
* 8O^x~[sQ
* @author [+WsVwyf?
*/ mu
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public class CountCache { ^y>V-R/N
public static LinkedList list=new LinkedList(); `he# !"
/** Creates a new instance of CountCache */ Qh@Q6
public CountCache() {} XGZZKvp
public static void add(CountBean cb){ `ulQ C
if(cb!=null){ ~?NCmU=3
list.add(cb); :3M,]W]
} UA.Tp [u
} _&=`vv'
} yD<#Q\,
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CountControl.java 91z=ou
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/*
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* CountThread.java q;AD#A|\
* ~T}D#}
* Created on 2007年1月1日, 下午4:57 }P2*MrkcHB
* Q^{TcL8
* To change this template, choose Tools | Options and locate the template under S[y'{;
* the Source Creation and Management node. Right-click the template and choose 2@(+l*.Q
* Open. You can then make changes to the template in the Source Editor. `
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*/ U,b80%k:
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package com.tot.count; (B\Kb4m
import tot.db.DBUtils; JSg=9p$
import java.sql.*; nIH(2j
/** ,U9j7E<4
* 6%EpF;T`
* @author 4"PA7
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*/ <w&'E6mU
public class CountControl{ A#$l;M.3R
private static long lastExecuteTime=0;//上次更新时间 fPJc
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 di_N}x*
/** Creates a new instance of CountThread */ -AnJLFY
public CountControl() {} _Nh])p-
public synchronized void executeUpdate(){ oxFd@WV5
Connection conn=null; ~/4j&IG
PreparedStatement ps=null; ~JZLWTEe
try{ J*g<]P&p0
conn = DBUtils.getConnection(); O#tmB?n*
conn.setAutoCommit(false); tln}jpCw
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); <c@dE
for(int i=0;i<CountCache.list.size();i++){ em'3 8L|(
CountBean cb=(CountBean)CountCache.list.getFirst(); Q-,
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CountCache.list.removeFirst(); k&yBB%g
ps.setInt(1, cb.getCountId()); W[QgddR
ps.executeUpdate();⑴ tQj=m_
//ps.addBatch();⑵ <> =(BAw
} 9on$0
//int [] counts = ps.executeBatch();⑶ >o"s1*
{
conn.commit(); v*excl~
}catch(Exception e){ KXTk.\c
e.printStackTrace(); L^^f.w#m
} finally{ G}
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try{ G]l/L\{
if(ps!=null) { 1
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ps.clearParameters(); d>M 0:
ps.close(); H"+|n2E^
ps=null;
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} W*H %\Y:N
}catch(SQLException e){} 6jr}l
DBUtils.closeConnection(conn); =[4C[s
} z@[n?t!7k
} lS;S:-
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public long getLast(){ \U]<HEc^
return lastExecuteTime; [HXd|,~_j-
} -{3^~vW|<
public void run(){ $LR~c)}1I
long now = System.currentTimeMillis(); #\~m}O,
if ((now - lastExecuteTime) > executeSep) { D6_#r=08
//System.out.print("lastExecuteTime:"+lastExecuteTime); 5'Mw{`
//System.out.print(" now:"+now+"\n"); %Y`)ZKh
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Mn\L55?E(
lastExecuteTime=now; ke*&*mx"L
executeUpdate(); @6 jKjI
} #SLiv
else{ `5t~
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1%.CtTi
} ~O;?;@
} cCtd\/ \
} MMRO@MdfV
//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 i+-Y"vRi
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类写好了,下面是在JSP中如下调用。 I~
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<% AxJf\B8
CountBean cb=new CountBean(); 0} \;R5a<
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 1
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CountCache.add(cb); G* mLb1
out.print(CountCache.list.size()+"<br>"); c_?!V
CountControl c=new CountControl(); S r7EcT-
c.run(); (>D{"}
out.print(CountCache.list.size()+"<br>"); ;f3))x
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