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: eG%Q
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CountBean.java dwmZ_m.
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/* o'!WW
* CountData.java 5+Hw @CY3
* Tw!_=zy(Gw
* Created on 2007年1月1日, 下午4:44 )X5en=[)O
* Schvwlm~i
* To change this template, choose Tools | Options and locate the template under 7=pJ)4;ZA
* the Source Creation and Management node. Right-click the template and choose kT4Oal+4
* Open. You can then make changes to the template in the Source Editor. Hb@PQcj
*/ UYsyVY`Fm|
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package com.tot.count; );*#s~R
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/** 3L-}B#tI
* 0 A6%!h
* @author 7A4_b8
*/ K5:>
public class CountBean { .u&GbM%Ga
private String countType; [TX5O\g![
int countId; /PgcW
/** Creates a new instance of CountData */ ^:,I #]
public CountBean() {} "[wP1n!G
public void setCountType(String countTypes){ "yc@_+"\+
this.countType=countTypes; qb>mUS
} V.~C.x
public void setCountId(int countIds){ j$}W%ibj
this.countId=countIds; dnstm@0k
} HbQ+:B]
public String getCountType(){ #~:@H&f790
return countType; o :_'R5
}
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public int getCountId(){ SMbhJ}\O
return countId; y<*/\]t9L[
} V"Y-|R
} ^RE("'+
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CountCache.java }?=4pGsI
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/* D7OPFN7`
* CountCache.java !F~*Q2PZ9
* "CF{Mu|Q=
* Created on 2007年1月1日, 下午5:01 /\|Behif
* l|'{Cb
* To change this template, choose Tools | Options and locate the template under 1g bqHxWI
* the Source Creation and Management node. Right-click the template and choose 0v'FE35~s
* Open. You can then make changes to the template in the Source Editor. |(O _K(
*/ H<bB@(i
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package com.tot.count; H\@@iK=
import java.util.*; G5'HrV
/** yfCdK-9+B
* &/tGT3)
* @author E>3(ff&
*/ A]q"+Z]
public class CountCache { 2]/[
public static LinkedList list=new LinkedList(); !i*bb~
/** Creates a new instance of CountCache */ OAd}#R\U
public CountCache() {} (| X?
public static void add(CountBean cb){ "[p-Iy1
if(cb!=null){ \1cJ?/$_Of
list.add(cb); DW.vu%j^[
} {G(N vf,K]
} LFT)_DG7(
} vILq5iR
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CountControl.java @>SirYh
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/* ;&MI
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* CountThread.java WwYy[3U
* |XoW
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* Created on 2007年1月1日, 下午4:57 fC^POLn[f
* !;~6nYY
* To change this template, choose Tools | Options and locate the template under nK;c@!~pS
* the Source Creation and Management node. Right-click the template and choose E G3?C
* Open. You can then make changes to the template in the Source Editor. 92)e/t iP
*/ @?\[M9yK
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package com.tot.count; mu#
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import tot.db.DBUtils; ?^z.WQ|f@
import java.sql.*; E4dN,^_ F!
/** H:>i:\J/M9
* 1.y|bB+kB
* @author K`#bLCXEV0
*/ N)N\iad^
public class CountControl{ Jx_BjkF
private static long lastExecuteTime=0;//上次更新时间 s6| S#
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |ZuS"'3_w
/** Creates a new instance of CountThread */ ^i!6q9<{e
public CountControl() {} "~^#{q
public synchronized void executeUpdate(){ yPhTCr5pK
Connection conn=null; U5x&?n<
PreparedStatement ps=null; cop \o4ia
try{ /R%
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conn = DBUtils.getConnection(); u?+i5=N9{
conn.setAutoCommit(false); 5$.e5y<&(
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); i$:QOMA
for(int i=0;i<CountCache.list.size();i++){ ;R8pVj!1f
CountBean cb=(CountBean)CountCache.list.getFirst(); "de3Sbj@?
CountCache.list.removeFirst(); ofIw7D*h
ps.setInt(1, cb.getCountId()); RNB ha&
ps.executeUpdate();⑴ C!Oz'~l
//ps.addBatch();⑵ Uc<j{U
,
} c-gpO|4>
//int [] counts = ps.executeBatch();⑶ POtwT">z
conn.commit(); (c=.?{U
}catch(Exception e){ }:2GD0Ru
e.printStackTrace(); rS^+y{7
} finally{ ]E!b&
try{ ytg' {)
if(ps!=null) { c mI&R(
ps.clearParameters(); uF89B-t
ps.close(); 236,o
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ps=null; 8%W(",nd
} N|53|H
}catch(SQLException e){} x vx+a0 A
DBUtils.closeConnection(conn); />q?H)6
} 1so9w89
} ;+-Dg3
public long getLast(){ 6o4Bf| E]
return lastExecuteTime; 5h6c W
} y-i6StJ
public void run(){ eW>Y*l%B
long now = System.currentTimeMillis(); a8wQ,
if ((now - lastExecuteTime) > executeSep) { e qzmEg
//System.out.print("lastExecuteTime:"+lastExecuteTime); OX!<{9o
//System.out.print(" now:"+now+"\n"); vv%
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9yt)9f
lastExecuteTime=now; PBo;lg`
executeUpdate(); qZz?i
} !9ytZR*
else{ ub,GF?9
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); )ir*\<6Y=
} [9U::
} +M^+qt;]V
} 3+>;$
//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 +J<igb!S
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类写好了,下面是在JSP中如下调用。 6Yu&'[?H$
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<% #'&&&_Hu3
CountBean cb=new CountBean(); eNEMyv5{w4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 1U(P0$C
CountCache.add(cb); 8+yCP_Y4
out.print(CountCache.list.size()+"<br>"); aUTXg60l*
CountControl c=new CountControl(); ta'{S=^j
c.run(); d=v{3*a_4,
out.print(CountCache.list.size()+"<br>"); ?wpS
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