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: #T=LR@y
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CountBean.java =t H:,SH
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/* Bx4w)9+3
* CountData.java Tw;3_Lj
* ([m
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* Created on 2007年1月1日, 下午4:44 Lja>8m
* xY^%&n
* To change this template, choose Tools | Options and locate the template under 75/(??2
* the Source Creation and Management node. Right-click the template and choose f m)pulz
* Open. You can then make changes to the template in the Source Editor. 'g
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*/ :6 Lx@
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package com.tot.count; sEGO2xeI
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/** ov_j4j>6P
* j;-1J_e5
* @author ? -dX`n
*/ ;E3>ay6m8
public class CountBean { <?riU\-]y
private String countType; ='s(|
int countId; D)m5
/** Creates a new instance of CountData */ sE Q=dcK
public CountBean() {} uYs5f.! `
public void setCountType(String countTypes){ 8L:ji,"
this.countType=countTypes; C,ARXW1
} \1fN0e
public void setCountId(int countIds){ \b?" b
this.countId=countIds; vnM@QfN
} rPLm5ni
public String getCountType(){ q#,f 4P
return countType; 7G}2,ueI
} Y6zbo
public int getCountId(){ 'kL#]
return countId; <~n"m
} @oV9)
} %&w3;d;c
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CountCache.java sP;nGQ.eN
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/* x:7b/j-
* CountCache.java !`,Sfqij
* QD:{U8YbF$
* Created on 2007年1月1日, 下午5:01 !O:y@
* y}My.c
* To change this template, choose Tools | Options and locate the template under 8o'_`{ba
* the Source Creation and Management node. Right-click the template and choose :+z4~%
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* Open. You can then make changes to the template in the Source Editor. "AnC?c9?-^
*/ ;h*K }U
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package com.tot.count; I+[>I=ewa
import java.util.*; T>2[=J8U
/** X[&Wkr8x '
* ymx>i~>7J
* @author ,^w?6?,&l}
*/ iw8yb;|z;A
public class CountCache { _/6!yyl
public static LinkedList list=new LinkedList(); zxbpEJzpn
/** Creates a new instance of CountCache */ MHX?@.
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public CountCache() {} i]6`LqlO
public static void add(CountBean cb){ ->g*</
if(cb!=null){ XINu=N(g
list.add(cb); g1W.mAA3B
} s'E2P[:
} ND>r#(_\
} :UF%K>k2
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CountControl.java ^Eb.:}!D6
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/* J;{N72
* CountThread.java Ay5i+)MD
* :y%/u%L
* Created on 2007年1月1日, 下午4:57 ER5gmmVP@p
* !Wy6/F@Z
* To change this template, choose Tools | Options and locate the template under ktFhc3);!
* the Source Creation and Management node. Right-click the template and choose k@f g(}6
* Open. You can then make changes to the template in the Source Editor. OwH81#
*/ p?);eJtV/
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package com.tot.count; D#il*
import tot.db.DBUtils; C)@y5. G;
import java.sql.*; a!<8\vzg
/** si`A:14R
* ,9}h
* @author ES.fOdx
*/ aI6$? wus
public class CountControl{ h]5C|M|
private static long lastExecuteTime=0;//上次更新时间 GqaDL3Niqs
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Jq&uF*!
/** Creates a new instance of CountThread */ i|w81p^o
public CountControl() {} (e!0]Io@
public synchronized void executeUpdate(){ J'SZ
Connection conn=null; 4'g;TI^
PreparedStatement ps=null; -0$55pa/@:
try{ >VP=MbN
conn = DBUtils.getConnection(); `\gnl'
conn.setAutoCommit(false); E*V`":efS
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); s.N7qO^:E
for(int i=0;i<CountCache.list.size();i++){ aE&,]'6
CountBean cb=(CountBean)CountCache.list.getFirst(); m#PY,y
CountCache.list.removeFirst(); Y^8C)p9r
ps.setInt(1, cb.getCountId()); E.7
ps.executeUpdate();⑴ e;Ti&o}
//ps.addBatch();⑵ !`g~F\l
} -@yh>8v
//int [] counts = ps.executeBatch();⑶ [ sN EHf
conn.commit(); tiB_a}5IB
}catch(Exception e){ 6r"eN%m
e.printStackTrace(); _aFl_\3>
} finally{ rz wF~-m +
try{ Oiz ,w7LRh
if(ps!=null) { hxVKV?Fl
ps.clearParameters(); s%C)t6`9
ps.close(); \O*-#} ~\
ps=null; TcjEcMw,
} 2N~Fg^xB
}catch(SQLException e){} m?pstuUK(
DBUtils.closeConnection(conn); h{HF8>u[
} =(NB%}
} AsAT_yv#
public long getLast(){ 4wa`<H&S5
return lastExecuteTime; QDs^Ije
} iOR_[ y,
public void run(){ F(k.,0Nc
long now = System.currentTimeMillis(); !MYSfPdS
if ((now - lastExecuteTime) > executeSep) { zLD0RBj7p
//System.out.print("lastExecuteTime:"+lastExecuteTime); T (OW
//System.out.print(" now:"+now+"\n"); v,
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); /<@SFF.
lastExecuteTime=now; *c~T@m~DR
executeUpdate(); !46RGU:I
} { /K.3
else{ WN{ 9
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0fF(Z0R,
} Pz>s6 [ob
} !c}O5TI|#
} Hyb3 ;yQ
//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 <3xyjX'NE
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类写好了,下面是在JSP中如下调用。 4}_j`d/8|
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<% *5vV6][
CountBean cb=new CountBean(); _LMM,!f
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); LR.Hh
CountCache.add(cb); TH; R
out.print(CountCache.list.size()+"<br>"); & -{DfNK c
CountControl c=new CountControl(); {5%5}[/x
c.run(); %\D)u8}
out.print(CountCache.list.size()+"<br>"); ud xZ0
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