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: ZV;#ZXch
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CountBean.java dC,F?^
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/* zKiKda%)
* CountData.java lX5(KUN
* 83TN6gW
* Created on 2007年1月1日, 下午4:44 qQpR gzw
* $)7-wCl</
* To change this template, choose Tools | Options and locate the template under p(0!TCBs
* the Source Creation and Management node. Right-click the template and choose (''`Ce
* Open. You can then make changes to the template in the Source Editor. yRieGf1'SD
*/ B*D`KA
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package com.tot.count; ;Rwr5
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/** yRvq3>mU
* OSkZW
* @author sBRw#xyS
*/ ,HMB`vF
public class CountBean { ^vG*8,^S=8
private String countType; 8swj'SjX
int countId; |L`w4;
/** Creates a new instance of CountData */ /6 P()Upe
public CountBean() {} ^8V]g1]fiG
public void setCountType(String countTypes){ y'4=
this.countType=countTypes; JN3Oe5yB2@
} o"UqI
public void setCountId(int countIds){ PkG+`N
this.countId=countIds; S4?ssI
} W*U\79H
public String getCountType(){ `?Y/:4
return countType; A E7>jkHB
} 7Bmt^J5i&t
public int getCountId(){ C'5i>;
return countId; :Z=A,G
} EzG7RjW
} #~p1\['|M
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CountCache.java vn,L),"=
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/* z
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* CountCache.java Y%wF;I1x
* >nl*aN
* Created on 2007年1月1日, 下午5:01 !vett4C* K
*
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* To change this template, choose Tools | Options and locate the template under \>I&UFfH)4
* the Source Creation and Management node. Right-click the template and choose TR:D
* Open. You can then make changes to the template in the Source Editor. "&C'K
*/ 4H1s"mP<
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package com.tot.count; DUW;G9LP$-
import java.util.*; u4.-AY {
/** g~Q#U;]
* pu `|HaQaE
* @author 2V F|T'h
*/ "t\rjFw
public class CountCache { 6dg[
public static LinkedList list=new LinkedList(); NrL%]dl3/
/** Creates a new instance of CountCache */ a(BC(^1!
public CountCache() {} S)Ld^0w
public static void add(CountBean cb){ V?5_J%
if(cb!=null){ //6m2a
list.add(cb); y4envjl0
} r}vI#;&
} .g4bV5ma3
} f#^%\K:YYR
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CountControl.java *M KVm)Iv
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/* ,L_p"A
* CountThread.java q+LjWZ+O
* P7@qvg
* Created on 2007年1月1日, 下午4:57 E[_Z%zd^
* <pPI:D@G
* To change this template, choose Tools | Options and locate the template under P^1rNB
* the Source Creation and Management node. Right-click the template and choose r*,]=M W
* Open. You can then make changes to the template in the Source Editor. `CHgTkv
*/ GbZA3.J]yl
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package com.tot.count; ]CHMkuP[k
import tot.db.DBUtils; #Q|$&b
import java.sql.*; !5=3Y4bg1
/** i4Fw+Z
* {OQ sGyR?
* @author q .?D{[2
*/ #UGbSOoCtn
public class CountControl{ oA42?I ^
private static long lastExecuteTime=0;//上次更新时间 8SKDL[rN
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 w@oq.K
/** Creates a new instance of CountThread */ VDQ&BmJE
public CountControl() {} LU%g>?m.]
public synchronized void executeUpdate(){ `D GO~RMp9
Connection conn=null; %*r Pd>*
PreparedStatement ps=null; Vuz!~kLYIn
try{ 8K1+ttjm
conn = DBUtils.getConnection(); \>jK\j
conn.setAutoCommit(false); fxiq,o0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 1hRC
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for(int i=0;i<CountCache.list.size();i++){ \3Xt\1qN4
CountBean cb=(CountBean)CountCache.list.getFirst(); 3btciR!N]
CountCache.list.removeFirst(); lz # inC|
ps.setInt(1, cb.getCountId()); Dcp,9"yt%
ps.executeUpdate();⑴ 0jg-]
//ps.addBatch();⑵ A)VOv`U@2
} B"{CWH O
//int [] counts = ps.executeBatch();⑶ %`gqV9a
conn.commit(); 6o6m"6
}catch(Exception e){ Ob(j_{m
e.printStackTrace(); -8TJ~t%w4
} finally{ T>LtN
try{ Q0M8}
if(ps!=null) { ]n!pn#Q
ps.clearParameters(); `d8$OC
ps.close(); tU?lfU[7
ps=null; ,,,5pCi\
} y6G[-?"/Q
}catch(SQLException e){}
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DBUtils.closeConnection(conn); =8<SKY&\X
} B|!YGfL
} SUvHLOA
public long getLast(){ r2H]n.MT
return lastExecuteTime; *Jp>)>
} u#}zNz#C5
public void run(){ 2>s:wABb /
long now = System.currentTimeMillis(); Ou,B3kuQ+
if ((now - lastExecuteTime) > executeSep) { &Cdd
//System.out.print("lastExecuteTime:"+lastExecuteTime); 67f#Z&r2k
//System.out.print(" now:"+now+"\n"); Ho\z^w+T`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); v'Lckw@G4
lastExecuteTime=now; f5`exfdHE
executeUpdate(); s<^UAdLnl
} 7]
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else{ B%r)~?6DM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); R':a,6O
} >\VZ9bP<
} 2"%d!"
} B\N,%vsx#U
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 \7Zk[)!FL
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类写好了,下面是在JSP中如下调用。 dyg1.n#M}
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<% k deJB-
CountBean cb=new CountBean(); "$m3xO
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {L.0jAwB
CountCache.add(cb); HW{+THNj
out.print(CountCache.list.size()+"<br>"); BeP0lZ
CountControl c=new CountControl(); !f"@pR6
c.run(); o<%Sr*
out.print(CountCache.list.size()+"<br>"); R#Ss_y
%>