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: L~6%Fi&n4
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CountBean.java i=EOk}R
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/* E%`J=C}
* CountData.java ",b:rgpRp
* Dx-P]j)4x
* Created on 2007年1月1日, 下午4:44 x]c8?H9,&
* ln82pQD2Y~
* To change this template, choose Tools | Options and locate the template under EH|+S
* the Source Creation and Management node. Right-click the template and choose <c}@lj-j
* Open. You can then make changes to the template in the Source Editor. KyyRHf5
*/ Y*c]C;%=
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package com.tot.count; $.jGO!
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/** jA{5)-g
* dQj/Sr
* @author OBAO(Ke
*/ %4*c/ c6
public class CountBean { |qw0:c=7!
private String countType; #3rS{4[
int countId; 8zx]/>
/** Creates a new instance of CountData */ %y6Q3@
public CountBean() {} ?),b902C
public void setCountType(String countTypes){ |Vpp'ipr
this.countType=countTypes; OMLU ;,4
} ^>IP"k F
public void setCountId(int countIds){ H3rA
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this.countId=countIds; =p@`bx
} !2|Lb'O
public String getCountType(){ cdMSC7l!
return countType; D^6*Cwb
} XG/xMz~
public int getCountId(){ ^+m`mc sE
return countId; LE8<JMB
} *k LFs|U
} huC{SzXM
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CountCache.java
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/* ]@$^Ju,
* CountCache.java cLZ D\1Mt
* ~~/,2^
* Created on 2007年1月1日, 下午5:01 RAO+<m
* ETHcZ
* To change this template, choose Tools | Options and locate the template under $wUYK%.
* the Source Creation and Management node. Right-click the template and choose =*\.zr
* Open. You can then make changes to the template in the Source Editor. c[Fc3
*/ _KH91$iW8m
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package com.tot.count; 60+ zoL'
import java.util.*; I0}.!
/** ukR0E4p
* U<j5s\Y,
* @author lCU clD
*/ & &}_[{fc
public class CountCache { P)Adb~r
public static LinkedList list=new LinkedList(); h[remR#3\
/** Creates a new instance of CountCache */ N
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public CountCache() {} W;OGdAa_
public static void add(CountBean cb){ Clum
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if(cb!=null){ P =X]'m_B
list.add(cb); =2p?_.|'
} (kxS0 ]=
} o,rF 15
} O=o}uB-*6
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CountControl.java T)zk2\u
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/* pQa51 nc
* CountThread.java xTAfVN
* F1yn@a "=J
* Created on 2007年1月1日, 下午4:57 );0
* 9kD#'BxC
* To change this template, choose Tools | Options and locate the template under 8T3,56>
* the Source Creation and Management node. Right-click the template and choose ^)dsi
* Open. You can then make changes to the template in the Source Editor. CPJ<A,V
*/ doanTF4Da
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package com.tot.count; |
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import tot.db.DBUtils; `PUqz&
import java.sql.*; }WsPu o
/** M}|(:o3Yo
* iE'_x$i
* @author lju5+0BSb
*/ 8&@=Anc&q
public class CountControl{ m^ xTV-#l@
private static long lastExecuteTime=0;//上次更新时间 e)e(f"t6Q
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 wC{sP"D
/** Creates a new instance of CountThread */ TZgtu+&
public CountControl() {} M1Q&)am
public synchronized void executeUpdate(){ |P5dv>tb
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Connection conn=null; 45JL{YRN
PreparedStatement ps=null; *Dg@fxCQ
try{ +
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conn = DBUtils.getConnection(); 9~UR(Ts}l
conn.setAutoCommit(false); hCQOwk#
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); pf8'xdExH)
for(int i=0;i<CountCache.list.size();i++){ [E9iuym
CountBean cb=(CountBean)CountCache.list.getFirst(); _`?0w#>0
CountCache.list.removeFirst(); :qo[@ x{
ps.setInt(1, cb.getCountId()); \n_7+[=E
ps.executeUpdate();⑴ ='"Yj
//ps.addBatch();⑵ q2%cLbI
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} {-5)nS^_
//int [] counts = ps.executeBatch();⑶ (pELd(*Ga
conn.commit(); ,buX|
}catch(Exception e){ uc,>VzdB
e.printStackTrace(); ;u2[Ww~k
} finally{ LDg9@esi
try{ &E`Nu (e
if(ps!=null) { B!&5*f}*
ps.clearParameters(); !td!">r46e
ps.close(); 2c Xae
ps=null; ^(;x-d3
} vsI;ooR>
}catch(SQLException e){} ROkwjw
DBUtils.closeConnection(conn); qJ;~ANwt
} sV"tN2W@
} %wbdg&^
public long getLast(){ )>ff"| X
return lastExecuteTime; ?i<l7
} <J^5l0)q
public void run(){ \6
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long now = System.currentTimeMillis(); L\4rvZa
if ((now - lastExecuteTime) > executeSep) { hrniZ^
//System.out.print("lastExecuteTime:"+lastExecuteTime); [+WsVwyf?
//System.out.print(" now:"+now+"\n"); mu
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?w/p 9j#
lastExecuteTime=now; |lLe^FM
executeUpdate(); g=td*S
} M{L<aYe
else{ Qh@Q6
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7#)k-S!B
} QbdXt%gZe
} dg|+?M^9`
} +Ug &
//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 x;[)#>.'
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类写好了,下面是在JSP中如下调用。 ?h `,@~6u
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<% 0s`6d;
CountBean cb=new CountBean(); o*$KiD
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); F.TIdkvp
CountCache.add(cb); 8fQ~UcT$
out.print(CountCache.list.size()+"<br>"); Gm-
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CountControl c=new CountControl(); 2[B bdg[O
c.run(); ,i*rHMe
out.print(CountCache.list.size()+"<br>"); E]q>ggeNH
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