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: bqw/O`*wfN
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CountBean.java h/0<:eZ*
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/* X_-Hrp!h
* CountData.java
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* cM> G>Yzo
* Created on 2007年1月1日, 下午4:44 ! /|0:QQi
* @1pW!AdN
* To change this template, choose Tools | Options and locate the template under .RQ Xxw
* the Source Creation and Management node. Right-click the template and choose Ct =E;v7}
* Open. You can then make changes to the template in the Source Editor. _Ep{|]:gw
*/ ~>}dse
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package com.tot.count; c t2_N
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/** ++J Bbuzj!
* .XV]<)<K$
* @author dK0}% ]i3#
*/ 3X-{2R/ 3
public class CountBean { %KabyvOl)
private String countType; Xhq? 7P$3
int countId; KRnB[$3F1
/** Creates a new instance of CountData */
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public CountBean() {} 2R_opbw
public void setCountType(String countTypes){ C,OB3y
this.countType=countTypes; G<">/_jn
} z{D$~ ob
public void setCountId(int countIds){ \28b_,i+
this.countId=countIds; ~# h E&nq
} K^]?@oHO
public String getCountType(){ Mv7w5vTl
return countType; FT3,k&i
} ~n8Oyr
public int getCountId(){ PK.h E{R
return countId; {|Mxvp*Hg
} xoz*UA.
} 8^P2GG'+-
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CountCache.java =#POMK".6
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/* #whO2Mv
* CountCache.java fJF8/IQ4
* V\k5h
* Created on 2007年1月1日, 下午5:01 7)8rc(58
* np'M4^E;
* To change this template, choose Tools | Options and locate the template under {jx#^n&5R
* the Source Creation and Management node. Right-click the template and choose ;H m-,W
* Open. You can then make changes to the template in the Source Editor. &geOFe}R
*/ 5H'b4Cyi`
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package com.tot.count; Ru9pb~K
import java.util.*; 6?<`wGs(
/** , IMT '*
* :uT
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* @author T_(e(5
*/ .=b
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public class CountCache { #RLch
public static LinkedList list=new LinkedList(); Q8DQ .C
/** Creates a new instance of CountCache */ )'K!)?&d
public CountCache() {} d 40'3]/{
public static void add(CountBean cb){ vZ_DG}n11
if(cb!=null){ W)$|Hm:H
list.add(cb); 5x1%oC
} cOZajC<G
} 9|G=KN)P:
} "b1R5(Ar
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CountControl.java %`s9yRk9>E
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/* ',J%Mv>Yf
* CountThread.java -?%{A%'
* M$>WmG1~D
* Created on 2007年1月1日, 下午4:57 *xZQG9`kt
* &t.>^7ELF
* To change this template, choose Tools | Options and locate the template under 8&2gM
* the Source Creation and Management node. Right-click the template and choose _,K>u6N&
* Open. You can then make changes to the template in the Source Editor. H~_^w.P
*/ RqX4ep5j
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package com.tot.count; N8L)KgM5#7
import tot.db.DBUtils; V"2AN3~&
import java.sql.*; [hv3o0".
/** n_xQSVI0F
* .2(@jx,[
* @author >ihe|WN
*/ ZZFI\o
public class CountControl{ 9TXm Z
private static long lastExecuteTime=0;//上次更新时间 cVP49r}}v
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |$|n V^y
/** Creates a new instance of CountThread */ *2m&?,nJ
public CountControl() {} t#D\*:Xi
public synchronized void executeUpdate(){ %.6?\w1e
Connection conn=null; _>?8eC ]4a
PreparedStatement ps=null; /J9T=N
try{ "` ?Wu
conn = DBUtils.getConnection(); rfZj8R&
conn.setAutoCommit(false); RQK**
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); whg4o|p
for(int i=0;i<CountCache.list.size();i++){ bcx{_&1p
CountBean cb=(CountBean)CountCache.list.getFirst(); <1'X)n&Kw$
CountCache.list.removeFirst(); 5f`XFe$8
ps.setInt(1, cb.getCountId()); @=zBF'<.9
ps.executeUpdate();⑴ }~\].I6
//ps.addBatch();⑵ n'ca*E(
} 1^H<+0
//int [] counts = ps.executeBatch();⑶ ^)0{42!]
conn.commit(); {</$ObK
}catch(Exception e){ )S;Xy`vO
e.printStackTrace(); `w+9j-
} finally{ 3sg)]3jm2
try{ _I70qz8
if(ps!=null) { ?BWvF]p5/
ps.clearParameters(); _^2[(<Gmv
ps.close(); $85o%siS'
ps=null; M:Y!k<p
} YT 03>!B
}catch(SQLException e){} '`goy%Wd
DBUtils.closeConnection(conn); CK`3
} }yC,uEV
} ,w58n%)H
public long getLast(){ kV(DnZ#jq
return lastExecuteTime; I#6'
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} oWaIjU0
public void run(){ HS&uQc a
long now = System.currentTimeMillis(); uF.\dY\xv
if ((now - lastExecuteTime) > executeSep) { r0$9c
//System.out.print("lastExecuteTime:"+lastExecuteTime); T I7Ty+s
//System.out.print(" now:"+now+"\n"); /qQ2@k
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]#7Y@Yo
lastExecuteTime=now; 4[EO[x4C
executeUpdate(); Nxs%~wZ
} ThQEQ6y
else{ Ynh4oWUp
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {^19.F
} kA:;c}p
} L!8?2 \5
} W2.1xNWO
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 6pz:Lfd80
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类写好了,下面是在JSP中如下调用。 Ug'nr
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<% 0@/E%T1c"
CountBean cb=new CountBean(); m&z%kVsg]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 7;s0m0<%~
CountCache.add(cb); :)V0zHo&(
out.print(CountCache.list.size()+"<br>"); hG3$ ]i9
CountControl c=new CountControl(); ~i&< !O&
c.run(); ToXFMkwY
out.print(CountCache.list.size()+"<br>"); fD}]Mi:V
%>