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: -Z)j"J
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CountBean.java X5i?Bb.
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/* |uT|(:i84,
* CountData.java Y?Ph%i2E
* ST'M<G%4E
* Created on 2007年1月1日, 下午4:44 !K:
* (ZR+(+i,
* To change this template, choose Tools | Options and locate the template under T:$ a
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* the Source Creation and Management node. Right-click the template and choose J8Bz|.@Q
* Open. You can then make changes to the template in the Source Editor. Ax &Z=
*/ @H%)!f]zWt
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package com.tot.count; .$nQD.X
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/** :u$nH9kwv
* -Lh\]
* @author 4cC
*/ nn'a`N
public class CountBean { LLE\ ;,bv
private String countType; GG0l\!2)
int countId; z7B>7}i-
/** Creates a new instance of CountData */ ~,j52obR6Z
public CountBean() {} hKa<9>MI`
public void setCountType(String countTypes){ {')L*
this.countType=countTypes; pW{Q%"W
} iZsZSW \
public void setCountId(int countIds){ (`C#Tq
this.countId=countIds; _}8hEv
} 45g:q
public String getCountType(){ hp ?4w) ,
return countType; H?-Byi
} ?#N:
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public int getCountId(){
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return countId; &>Zm gz
} *4]u?R
} / =]h@m-`
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CountCache.java }_,\yC9F
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/* OH.lAF4E(
* CountCache.java c~1+5&
* M8_f{|!&
* Created on 2007年1月1日, 下午5:01 zVEG)
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* Kkfz a
* To change this template, choose Tools | Options and locate the template under Ep>} S
* the Source Creation and Management node. Right-click the template and choose =|}_ASbzw
* Open. You can then make changes to the template in the Source Editor. AkMP)\Q
*/ ^,-2";2Xh
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package com.tot.count; q!L@9&KAQ
import java.util.*; *dmBJi}
/** S10"yhn(-t
* > nHaMj
* @author xxnvz
*/ Gm`#0)VC
public class CountCache { =()Vrk|uK
public static LinkedList list=new LinkedList(); CG[2
/** Creates a new instance of CountCache */ asEk3
public CountCache() {} {J&[JA\
public static void add(CountBean cb){ sej$$m R
if(cb!=null){ ?/@U#Qy
list.add(cb); ww? AGd
} k -V3l
} _%R]TlL
} \ 8v^ hb
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CountControl.java `;~A
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/* 7.mYzl-F(
* CountThread.java =Ch^;Wyt
* ]z77hcjB1
* Created on 2007年1月1日, 下午4:57 0jJ:WPR
* Q[n*ce7L0
* To change this template, choose Tools | Options and locate the template under o;kxu(>yL'
* the Source Creation and Management node. Right-click the template and choose @ajt
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* Open. You can then make changes to the template in the Source Editor. \rpXG9
*/ E4QLXx6Wa&
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package com.tot.count; TSKT6_IJw
import tot.db.DBUtils; .&i_~?1[N
import java.sql.*; 7 /6Zp?
/** u7/]Go44
* ljP<WD
* @author btR~LJb
*/ VbI$#;:[7
public class CountControl{ H`bS::JI-
private static long lastExecuteTime=0;//上次更新时间 M!Ua/g=u
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *|4/XHi
/** Creates a new instance of CountThread */ H$ZLtPv5
public CountControl() {} (Q?@LzCjy
public synchronized void executeUpdate(){ ]x(cX&S-9
Connection conn=null; 0-Ga2Go9
PreparedStatement ps=null; }?)U`zF)7}
try{ e>T;'7HSS"
conn = DBUtils.getConnection(); (V x2*Aw]
conn.setAutoCommit(false); /(u# D[
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); G' '9eV$
for(int i=0;i<CountCache.list.size();i++){ hiKyU!)Hv
CountBean cb=(CountBean)CountCache.list.getFirst(); =E
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CountCache.list.removeFirst(); eH]9"^>
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ps.setInt(1, cb.getCountId()); *djVOC
ps.executeUpdate();⑴ $
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//ps.addBatch();⑵ U#G<cV79
} k`((6
//int [] counts = ps.executeBatch();⑶ -A,UqEt
conn.commit(); /.WIED}>
}catch(Exception e){ 5AK@e|G$w
e.printStackTrace(); ,m Nd#
} finally{ #62*'.B4
try{ |ju+{+
if(ps!=null) { "Q`Le{
ps.clearParameters(); 7<ZGNxZ~
ps.close(); $ ~%w21?&
ps=null; N9#5 P!
} d=0{vsrB
}catch(SQLException e){} qjsEyro$-
DBUtils.closeConnection(conn); dsn(h5,Q'
} TbD
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} T#\=v(_NR
public long getLast(){ 5\Rg%Ezl
return lastExecuteTime; TQtHU6
} }9V0Cu1
public void run(){ Px3I+VP
long now = System.currentTimeMillis(); yAFt|<
if ((now - lastExecuteTime) > executeSep) { 3Rhoul[S
//System.out.print("lastExecuteTime:"+lastExecuteTime); j 8)*'T
//System.out.print(" now:"+now+"\n"); `MHixQ;j
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); dT{GB!jz
lastExecuteTime=now; # w@FBFr@
executeUpdate(); h[;DRD!Z
} PXG@]$~3
else{ TBIr^n>Z<k
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6!HYx
} nsM.`s@V
} I
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} 8!b>[Nsc
//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 RBfzti6
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类写好了,下面是在JSP中如下调用。 ^Kl*}
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<% :r2d%:h%2
CountBean cb=new CountBean(); WL|<xNL
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); u_}UU
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CountCache.add(cb); dOK]Su
out.print(CountCache.list.size()+"<br>"); iL!4r]~H
CountControl c=new CountControl(); E5#ff5
c.run(); Y_6v@SiO
out.print(CountCache.list.size()+"<br>"); oWx^_wQ-=
%>