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: ud`.}H~aB
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CountBean.java OwQ 9y<v
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/* OX?9 3AlG
* CountData.java >29eu^~nh
* Z<|caT]Q(
* Created on 2007年1月1日, 下午4:44 P$)9osr
* x
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* To change this template, choose Tools | Options and locate the template under |Js96>B:
* the Source Creation and Management node. Right-click the template and choose ~} mX#,
* Open. You can then make changes to the template in the Source Editor. t?v0ylN
*/ 3Nh;^
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package com.tot.count; flLC\
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/** cmu5KeH
* ~S
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* @author XQk9 U
*/ 0X)'8N
public class CountBean { %+G/oF|
private String countType; hSD)|
int countId; {
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/** Creates a new instance of CountData */ fj 19U9R
public CountBean() {} r&\}E+
public void setCountType(String countTypes){ +gOCl*L
this.countType=countTypes; *kxk@(lT?
} 6yF4%Sz9
public void setCountId(int countIds){ "_C^Bc
this.countId=countIds; yi7-[W}
} >;QkV6i7
public String getCountType(){ -)?~5Z
return countType; u9>.x
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} "wxs
public int getCountId(){ q]5"V>D \
return countId; FI~)ZhE)]
} vdNh25a<h
} HF5aU:M
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CountCache.java
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/* e9q/[xMi
* CountCache.java iYv6B6o/99
* P7E}^y`e
* Created on 2007年1月1日, 下午5:01 5gV8=Ml"V
* ag?@5q3J}
* To change this template, choose Tools | Options and locate the template under L"tj DAV
* the Source Creation and Management node. Right-click the template and choose ^?toTU
* Open. You can then make changes to the template in the Source Editor. _q=$L
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*/ /Yx 1S'5
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package com.tot.count; s+^o[R
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import java.util.*; >lyUr*4PX
/** X<(h)&E
* k KL^U
* @author (J<@e!@NE
*/ )u]<8
public class CountCache { Tc\^=e^N?
public static LinkedList list=new LinkedList(); S_6`.@B}
/** Creates a new instance of CountCache */ 7esG$sVj(
public CountCache() {} tZU"Ud
public static void add(CountBean cb){ 2X)E3V/*
if(cb!=null){ Z[AJat@H
list.add(cb); E] t:_v
} J(M0t~RZ
} ez86+
} T[<llh'+
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CountControl.java QhZ!A?':U
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/* ssi{(}H/Jv
* CountThread.java cWp
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* Iu(T@",Q#
* Created on 2007年1月1日, 下午4:57 YT,1E>rd
* >H5BY9]I
* To change this template, choose Tools | Options and locate the template under v>)[NAY9
* the Source Creation and Management node. Right-click the template and choose +tkd($//
* Open. You can then make changes to the template in the Source Editor. m3 (fr
*/ .K}u`v T
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package com.tot.count; g;v{JB
import tot.db.DBUtils; zG@9-s* L
import java.sql.*; F>n<;<
/** Si*Pi
* xHykU;p@
* @author .m/Lon E
*/ 0'BR Sa<
public class CountControl{ 2{XQDOyA
private static long lastExecuteTime=0;//上次更新时间 U`<EpO{j|
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 G~a/g6M4
/** Creates a new instance of CountThread */ yKOf]m>#
public CountControl() {} YcRjbF,|6
public synchronized void executeUpdate(){ ?8! 4!P%n
Connection conn=null; '/;#{("
PreparedStatement ps=null; *-_` xe
try{ ):LJ {.0R
conn = DBUtils.getConnection(); _\sm$ `q
conn.setAutoCommit(false); UH%?{>oRh
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Cl<`uW3
for(int i=0;i<CountCache.list.size();i++){ q'+XTal
CountBean cb=(CountBean)CountCache.list.getFirst(); k%NY,(:(
CountCache.list.removeFirst(); -hp,O?PM
ps.setInt(1, cb.getCountId()); 8,dCx}X
ps.executeUpdate();⑴ 0NpxqeIDY
//ps.addBatch();⑵ )/bt/,M&}
} _h@7>+vl~
//int [] counts = ps.executeBatch();⑶ &sJpn*W
conn.commit(); pVt-7AgW
}catch(Exception e){ I g-VSQ
e.printStackTrace(); Ao`9 fI#q
} finally{ ;n7k_K#0z!
try{ %>xW_5;Z
if(ps!=null) { .b N0!
ps.clearParameters(); 8dIgw
ps.close(); L V33vy
ps=null; wOHK
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} wc~a}0uz
}catch(SQLException e){} I.y|AQB
DBUtils.closeConnection(conn); e#kPf 'gL
} s;8J= \9W
} T"9`[Lzva
public long getLast(){ &ks>.l\
return lastExecuteTime; G0> 'H1 Z
} b4ORDU
public void run(){ go2:D#mf
long now = System.currentTimeMillis(); 0
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if ((now - lastExecuteTime) > executeSep) { b0LQ$XM>8
//System.out.print("lastExecuteTime:"+lastExecuteTime); rx_'(
//System.out.print(" now:"+now+"\n"); N[aK#o,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {x2N~1!E
lastExecuteTime=now; [_-CO}>
executeUpdate(); 1#]tCi`
} y7d)[d*Mz
else{ 4y
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); a4g=cs<9}
} vWe)c J
}
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} `j4ukOnG
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 C&<f YCwG
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类写好了,下面是在JSP中如下调用。 ?$-OdABXHK
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<% HOykmx6$
CountBean cb=new CountBean(); lP9a*>=a
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 2',t@< U
CountCache.add(cb); rCYNdfdpp
out.print(CountCache.list.size()+"<br>"); 1/a*8vuGh
CountControl c=new CountControl(); 1v`<Vb%"}T
c.run(); _k5KJKvr
out.print(CountCache.list.size()+"<br>"); vuDp_p*]S
%>