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: aEcktg6h
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CountBean.java B0-4ZT
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/* KU1+<OCh
* CountData.java b}ySZlmy
* cxtLy&C
* Created on 2007年1月1日, 下午4:44 hg%@ W
* T)b3N|ONB
* To change this template, choose Tools | Options and locate the template under iifc;6 2
* the Source Creation and Management node. Right-click the template and choose a"`g"ZRx
* Open. You can then make changes to the template in the Source Editor. ) 1lJ<g#
*/ mtSNl|O&{
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package com.tot.count; UI|v/(_^F
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/** "\VW.S
* t`
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* @author 9F2w.(m
*/ c*y$bf<
public class CountBean { P`\m9"7
private String countType; S/@dkHI'
int countId; B'G*y2UnG
/** Creates a new instance of CountData */ /2g)Z!&+L
public CountBean() {} %k/
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public void setCountType(String countTypes){ iYO
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this.countType=countTypes; (t]lP/
} E[ )7tr
public void setCountId(int countIds){ j[$B\H
this.countId=countIds; >u BV
}
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public String getCountType(){ ~[d=s
return countType; Nb^zkg
} /3)YWFZZc
public int getCountId(){ u~/M
return countId; !A'`uf4u
} zCK y`u.
} |1dEs,z\
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CountCache.java OmT Z-*N
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/* eh({K;>
* CountCache.java ]C}u-B746
* es.\e.HK
* Created on 2007年1月1日, 下午5:01 ,cGwtt(
* ,Az`6PW
* To change this template, choose Tools | Options and locate the template under &=s|
* the Source Creation and Management node. Right-click the template and choose 6e$sA (a=i
* Open. You can then make changes to the template in the Source Editor. 9B!im\]O
*/ 4i+PiD:H
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package com.tot.count; {V]Qwz)1
import java.util.*; ]MqH13`)A
/** w8m8r`h
* @e.OU(Bf
* @author jV,(P$ 5;
*/ V e$5w}a4
public class CountCache { "oE^R?m
public static LinkedList list=new LinkedList(); D,}'E0
/** Creates a new instance of CountCache */ $nGbT4sc
public CountCache() {} Z,|1G6f@
public static void add(CountBean cb){ f_re"d 3u
if(cb!=null){ 5{R#h :
list.add(cb); dI#8CO
} M5cOz|j/*R
} `_ J^g&y~
} b2/N H1A
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CountControl.java SQ~N X)
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/* :|n>H+Y
* CountThread.java X%4uShM
* `5k6s,
* Created on 2007年1月1日, 下午4:57 o@<6TlZM
* c:h.J4mv
* To change this template, choose Tools | Options and locate the template under Ac5o K
* the Source Creation and Management node. Right-click the template and choose O?j98H
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* Open. You can then make changes to the template in the Source Editor. CfkNy[}=
*/ dbMu6Bm\G
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package com.tot.count; DuO%B
import tot.db.DBUtils; V 9QvQA
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import java.sql.*; dVsAX(
/** 4,w{rmj
* 0TuOY%+
* @author 68'-1}
*/ Z!*8JaMT
public class CountControl{ JGSk4
private static long lastExecuteTime=0;//上次更新时间 }l]3m=)
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 pU:C=hq4
/** Creates a new instance of CountThread */ &m%Pr
public CountControl() {} L!8 -:)0b
public synchronized void executeUpdate(){ DmXDg7y7s
Connection conn=null; CD8JY iJ
PreparedStatement ps=null; aiR|.opIb
try{ uJIRk$
conn = DBUtils.getConnection(); @ V7ooo!
conn.setAutoCommit(false); Z5*(W;;
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); }GoOE=rhY
for(int i=0;i<CountCache.list.size();i++){ P[#WHbn
CountBean cb=(CountBean)CountCache.list.getFirst(); qOcG|UgF
CountCache.list.removeFirst(); aV?}+Y{#
ps.setInt(1, cb.getCountId()); skR,M=F~
ps.executeUpdate();⑴ 9aF..
//ps.addBatch();⑵ :b M$;
} /v
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//int [] counts = ps.executeBatch();⑶ RXx?/\~yd;
conn.commit(); qa0JQ_?o]
}catch(Exception e){ 3I>S:|=K
e.printStackTrace(); Cb@S </b
} finally{ ohc/.5Kl
try{ <PfPh~
if(ps!=null) { _ntW}})K
ps.clearParameters(); < ;%q
ps.close(); !0. 5
ps=null; pzt Zb
} 8)-t91hkL
}catch(SQLException e){} vYMbson}
DBUtils.closeConnection(conn); 6XOpB^@
} zNsL^;uT
} -X&!dV:= 4
public long getLast(){ J++sTQ(!?
return lastExecuteTime; "f&i 251
} ?) ,xZ1"
public void run(){ n6%jhv9H
long now = System.currentTimeMillis(); ;8;~C"
if ((now - lastExecuteTime) > executeSep) { tRUsZl
//System.out.print("lastExecuteTime:"+lastExecuteTime); 6t7;}t]t
//System.out.print(" now:"+now+"\n"); >+;
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 4M0v1`k
lastExecuteTime=now; ,3@15j
executeUpdate(); :|m~<'g
} vY0V{u?J
else{ LG&Q>pt.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); '#4mDz~
} QzFv ;
} &Xl_sDvt
} z[lRb]:i[
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 m|ERf 2-
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类写好了,下面是在JSP中如下调用。 l6`d48U
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<% YAC zznN
CountBean cb=new CountBean(); )(ZPSg$/F
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); zy/tQGTr@
CountCache.add(cb); #`vGg9
out.print(CountCache.list.size()+"<br>"); ILr6W@o5A
CountControl c=new CountControl(); ^pQ;0[9Y0
c.run(); vn%U;}
out.print(CountCache.list.size()+"<br>"); %\{?(baOA
%>