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: R {HV]o|qk
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CountBean.java 3gAR4
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/* \[yr=X
* CountData.java j&5G\6:
* >c<pDNt?
* Created on 2007年1月1日, 下午4:44 [F+(^- (
* ~g6"'Cya?k
* To change this template, choose Tools | Options and locate the template under e}c&LDgU
* the Source Creation and Management node. Right-click the template and choose `ncNEHh7K
* Open. You can then make changes to the template in the Source Editor. \)OEBN`9#
*/ !xu9+{-
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package com.tot.count; bNGCOj
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/** B
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* T-'~? [v
* @author ow$q7uf
*/ kY"KD22a
public class CountBean { F$Hx`hoy
private String countType; 69-:]7.g
int countId; #)o7"PW:
/** Creates a new instance of CountData */ CK0l9#g
public CountBean() {} 3X;{vO\a1
public void setCountType(String countTypes){ Zb(E:~h\
this.countType=countTypes; AEY$@!8
} [ $pmPr2
public void setCountId(int countIds){ j(iuz^I
this.countId=countIds; ~:4~2d|
} =. *98
public String getCountType(){ t6+YXjXK
return countType; B:<
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} y`yZR
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public int getCountId(){ kbYeV_OwM
return countId; Bq@zaMv
} iib
} LvcuZZ`1a
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CountCache.java ]ab#q=
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/* Tkw;pb
* CountCache.java LH2PTW\b!6
* }u%"$[I}
* Created on 2007年1月1日, 下午5:01 sYqgXE.
* y500Xs[c
* To change this template, choose Tools | Options and locate the template under i0:>Nk
* the Source Creation and Management node. Right-click the template and choose UL(
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* Open. You can then make changes to the template in the Source Editor. j?6X1cM q
*/ 2C$R4:Ssw)
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package com.tot.count; 06 i;T~Y
import java.util.*; o%`Xa#*Ly
/** im]g(#GnKh
* G,XPT,:%
* @author d;7uFh|o
*/ m}3gZu]
public class CountCache { s
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public static LinkedList list=new LinkedList(); ?<U{{C
/** Creates a new instance of CountCache */ =Q<L
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public CountCache() {} kkS~4?-*
public static void add(CountBean cb){ @%hCAm
if(cb!=null){ .&1C:>
list.add(cb); QJn`WSw$_-
} C3XmK}h
} &H||&Z[pk
} M6rc!K
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CountControl.java 9MY7a=5E~
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/* \(
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* CountThread.java [8XLK 4e
* ?kTWpXx"=
* Created on 2007年1月1日, 下午4:57 $s\UL}Gc
* ;@3FF
* To change this template, choose Tools | Options and locate the template under FS"eM"z
* the Source Creation and Management node. Right-click the template and choose wW 2d\Zd&
* Open. You can then make changes to the template in the Source Editor. 4/e60jA
*/ egk7O4zwP
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package com.tot.count; _Ov;4nt!
import tot.db.DBUtils; &QNY,Pj
import java.sql.*; ;sPoUn
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/** e`K)_>^n#
* ]Mi.f3QlO6
* @author "*z_O
*/ @U{<a#
public class CountControl{ ,=QM#l]
private static long lastExecuteTime=0;//上次更新时间 Ju2l?RrX
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 8RW&r
/** Creates a new instance of CountThread */ V\]" }V)"
public CountControl() {} p(F " /
public synchronized void executeUpdate(){ /9pM>Cd*Z
Connection conn=null; $ ((6=39s
PreparedStatement ps=null; (ljF{)Ml+=
try{ I$t3qd{H&
conn = DBUtils.getConnection(); _>m-AI4^
conn.setAutoCommit(false); 44ed79ly0)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); q.#[TI ^
for(int i=0;i<CountCache.list.size();i++){ ccFn.($p?,
CountBean cb=(CountBean)CountCache.list.getFirst(); .w?(NZ2~
CountCache.list.removeFirst(); 69K{+|
ps.setInt(1, cb.getCountId()); ->^~KVh&
ps.executeUpdate();⑴ N|g;W
//ps.addBatch();⑵ )~J>X{hy
} !7bw5H
//int [] counts = ps.executeBatch();⑶ ~EzaC?fQ
conn.commit(); GoM
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}catch(Exception e){ !y:%0{l
e.printStackTrace(); @|}BXQNd
} finally{ +|iYg/2
try{ Q/ms]Du
if(ps!=null) { N6OMYP1
ps.clearParameters(); /93l74.w
ps.close(); wC_l@7t
ps=null; epHJ@ W@#
} #H?t!DU
}catch(SQLException e){} !$;a[Te
DBUtils.closeConnection(conn); I04jjr:<
} gi/@j
} $2^`Uca
public long getLast(){ + @9.$6N
return lastExecuteTime;
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} j%u-dr
public void run(){ N,dT3we
long now = System.currentTimeMillis(); M 3 '$[
if ((now - lastExecuteTime) > executeSep) { f/,>%j=Ms
//System.out.print("lastExecuteTime:"+lastExecuteTime); _@mRb^
//System.out.print(" now:"+now+"\n"); CT9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); xT&(n/
lastExecuteTime=now; 2T@GA1G
executeUpdate(); kd`0E-QU
}
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else{ 7?8wyk|x
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {5r0v#;
} >T2LEW
} E/&Rb*3
} Migd(uw'
//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 FWue;pw3
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类写好了,下面是在JSP中如下调用。 =*qD4qYA
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<% DS-0gVYeDW
CountBean cb=new CountBean(); ?[<Tx-L
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); tM-^<V&
CountCache.add(cb); VErv;GyV
out.print(CountCache.list.size()+"<br>"); h&.wo !
CountControl c=new CountControl(); {>LIMG-f
c.run(); D4eTTfQ
out.print(CountCache.list.size()+"<br>"); tWTKgbj(
%>