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: yj^LX2x"
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CountBean.java ~*3obZ2>2
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/* ){AtV&{$
* CountData.java V~Zi #o
* ]x8_f6;D
* Created on 2007年1月1日, 下午4:44 0!D,74r
* L[]*vj
* To change this template, choose Tools | Options and locate the template under F:PaVr3q
* the Source Creation and Management node. Right-click the template and choose u|!On
* Open. You can then make changes to the template in the Source Editor. 0ssKZ9Lc
*/ *V\z]Dy-[
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package com.tot.count; b8?qYm
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/** e}x}Fj</(
* r/X4Hy0!lT
* @author LvWl*:z
*/ ,0'Yj?U>
public class CountBean { ")/TbTVu
private String countType; hX-([o
int countId; vv2N;/;I
/** Creates a new instance of CountData */ +GgJFBl
public CountBean() {} AL%gqt]
public void setCountType(String countTypes){ E8TJ*ZU
this.countType=countTypes; U~~Y'R\NU
} )KZ1Z$<
public void setCountId(int countIds){ i6"/GSA
this.countId=countIds; yI&{8DCCw
} [}7j0&
public String getCountType(){ O*hd@2hd
return countType; xvZNshkpAX
} dQoZhE
public int getCountId(){ Uoskfm
return countId; D;f[7Cac
} g/)$-Z)Nu
} }PZz(Ms
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CountCache.java .k{omr&Dy5
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/* \JJ>y
* CountCache.java pK)*{fC$`
* p^2"g~
* Created on 2007年1月1日, 下午5:01 '}3m('u
* T6X%.tR>`
* To change this template, choose Tools | Options and locate the template under 'C
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* the Source Creation and Management node. Right-click the template and choose rAc
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* Open. You can then make changes to the template in the Source Editor. #q;hX;Va
*/ wzw`9^B
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package com.tot.count; [C GFzxz$
import java.util.*; .U8Se+;
/** ]dXHjOpA
* rsbdDTy
* @author x+kP,v
*/ -ff|Xxar{
public class CountCache { -{Lc?=
public static LinkedList list=new LinkedList(); kI|Vv90l
/** Creates a new instance of CountCache */ FiTP-~
public CountCache() {} "3!!G=s P
public static void add(CountBean cb){ .YvE
if(cb!=null){ }yCw|B|a
list.add(cb); 0nkon3H
} -rU~
} 2gn*B$a
} n-h2SQl!
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CountControl.java 5:jbd:o
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^
/* e=11EmN9
* CountThread.java ];bl;BP
* Z[.+Wd\)-9
* Created on 2007年1月1日, 下午4:57 us&!%`
* _9Pxtf
* To change this template, choose Tools | Options and locate the template under >".,=u'
* the Source Creation and Management node. Right-click the template and choose ]J^9iDTTA
* Open. You can then make changes to the template in the Source Editor. .s4hFB^n
*/ U] 2fV|Hn
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package com.tot.count; 9aLS%-x!+
import tot.db.DBUtils; O[p;IG`
import java.sql.*; ,hj5.;M
/** zVLv-U/=d
* ?[4!2T,Ca
* @author ,&S^R yc
*/ #+V5$
public class CountControl{ FHNK%Ko
private static long lastExecuteTime=0;//上次更新时间 Oeo:V"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 H].G%,2'
/** Creates a new instance of CountThread */ Onr#p4UT
public CountControl() {} Luxo,Ve
public synchronized void executeUpdate(){ 1vcI`8%S+u
Connection conn=null; M@a?j<7P,m
PreparedStatement ps=null; zu<8%
try{ SnK j:|bV
conn = DBUtils.getConnection(); |aiP7C
conn.setAutoCommit(false); %IS'R`;3
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); O*3x'I*a
for(int i=0;i<CountCache.list.size();i++){ {}?;|&_
CountBean cb=(CountBean)CountCache.list.getFirst(); ?Gq'r2V
CountCache.list.removeFirst(); )z0qKb\
ps.setInt(1, cb.getCountId()); xF)AuGdp\
ps.executeUpdate();⑴ mU1lEx$
//ps.addBatch();⑵ 1sFTXl
} WA-`
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//int [] counts = ps.executeBatch();⑶ m`<Mzk.u<
conn.commit(); RUTlwTdv
}catch(Exception e){ h+mM
e.printStackTrace(); I)~&6@Jn
} finally{ z/*nY?
try{ Si<9Oh
if(ps!=null) { _m!TUT8o
ps.clearParameters(); W11Wv&
ps.close(); wj>mk
ps=null; aa<9%j
} ?iH`-SY
}catch(SQLException e){} Ti/t\'6
DBUtils.closeConnection(conn); i/rdPbq
} /#Y)nyE
} pv2_A
public long getLast(){ DXlP(={*
return lastExecuteTime; %H:uE*WZ
} W1X\!Y
public void run(){ Wjt1NfS&
long now = System.currentTimeMillis(); `nccRy<l
if ((now - lastExecuteTime) > executeSep) { a^qLyF&F
//System.out.print("lastExecuteTime:"+lastExecuteTime); Nw@tlT4
//System.out.print(" now:"+now+"\n"); DG8LoWZ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >;',U<Wd
lastExecuteTime=now; 1xM'5C?~7
executeUpdate(); ?2VY^7N[
} i^ 9PiP|U
else{ OYGh!sW
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); (yFR;5Fo
} PMk3b3)Z
} hd~X c
} v\*43RL
//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 jsSxjf;O
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类写好了,下面是在JSP中如下调用。 )rv5QH`i
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<% -|mWi
CountBean cb=new CountBean(); .5I!h !
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ]trVlmZXH}
CountCache.add(cb); r]eeKV,{p
out.print(CountCache.list.size()+"<br>"); 6#XB'PR2p
CountControl c=new CountControl(); ODK$G
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c.run(); Y:C7S~
out.print(CountCache.list.size()+"<br>"); E
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