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: Btc[
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CountBean.java ;i 3C
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/* ?j}
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* CountData.java oMN
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* e#?rK=C?9
* Created on 2007年1月1日, 下午4:44 'EkjySZ]F{
* X|60W
* To change this template, choose Tools | Options and locate the template under <|:$_&(
* the Source Creation and Management node. Right-click the template and choose `iwGPG!
* Open. You can then make changes to the template in the Source Editor. 3d_g@x#9
*/ )KY U[
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package com.tot.count; =&vRT;6
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/** {.UK{nA?sm
* ;S+"z;$m
* @author m9aP]I3g]\
*/ .r-kH&)"GU
public class CountBean { }cg 1CT5
private String countType; Zb~G&.
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int countId; Zg >!5{T
/** Creates a new instance of CountData */ g^:7mG6C
public CountBean() {} o(xt%'L`t
public void setCountType(String countTypes){ vu/P"?F
this.countType=countTypes; LeMo")dk\
} _Tma1~Gq
public void setCountId(int countIds){ 0O?!fd n
this.countId=countIds; R"QWap}
} f<@`{oP@
public String getCountType(){ $`/F5R!
return countType; mmEe@-lE
} ~G~:R
public int getCountId(){ 0"`|f0}c
return countId; "=9)|{=m
} @z(s\T
} m pM,&7}
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CountCache.java Oxh.&
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/* [JVUa2Sm
* CountCache.java T-lHlm
* "ODs.m oq
* Created on 2007年1月1日, 下午5:01 &4Y@-;REt
* [b@9V_
* To change this template, choose Tools | Options and locate the template under n UD;y}}n
* the Source Creation and Management node. Right-click the template and choose w;T?m,"
* Open. You can then make changes to the template in the Source Editor. HQ3kxOT
*/ *lp{,
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package com.tot.count; `,FvYA"
import java.util.*; 4iZ7BD
/** |_wbxdq
* `"j _]
* @author :FI4GR*?
*/ XFvPc
public class CountCache { 5E\&O%W"
public static LinkedList list=new LinkedList(); ixo?o]Xb`
/** Creates a new instance of CountCache */ @*~cmf&FIQ
public CountCache() {} `z`"0;,7S
public static void add(CountBean cb){ |'12Kv]#Xa
if(cb!=null){ </7?puVR
list.add(cb); 0'^zIL#.
} >J@hqW
} }9(:W </}
} 4031~A8
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CountControl.java Vu1X@@z
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/* sVT\e*4m}
* CountThread.java =h}IyY@o
* %%k`+nK~
* Created on 2007年1月1日, 下午4:57 k&\ 6SK/
* lnRbvulH
* To change this template, choose Tools | Options and locate the template under /'>#1J|TlK
* the Source Creation and Management node. Right-click the template and choose '~kAsn*/
* Open. You can then make changes to the template in the Source Editor. KN zm)O
*/ iY4FOt7\
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package com.tot.count; o_ SR
import tot.db.DBUtils; npdpKd+*K"
import java.sql.*; {!7 ^w
/** t0gLz
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* 5oE!^bF?
* @author (8OaXif
*/ Q:!.YSB
public class CountControl{ M}tr*L
private static long lastExecuteTime=0;//上次更新时间 hKYA 5]
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 JGKiVBN
/** Creates a new instance of CountThread */ IH0qx_;P&
public CountControl() {} )]C7+{ImC
public synchronized void executeUpdate(){ 9DP6g<>B
Connection conn=null; kkE1CHY
PreparedStatement ps=null; a).bk!G
try{ +MP`iuDO
conn = DBUtils.getConnection(); 2kU=9W6ND
conn.setAutoCommit(false); Td>Lp=0rU
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); RA~%Cw4t
for(int i=0;i<CountCache.list.size();i++){ N_"mC^Vx
CountBean cb=(CountBean)CountCache.list.getFirst(); ,
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CountCache.list.removeFirst(); 1]vrpJw
ps.setInt(1, cb.getCountId()); 7ehs+GI
ps.executeUpdate();⑴ F82_#|kpS
//ps.addBatch();⑵ K\]ey;Bd
} 6?v)Hb}J%d
//int [] counts = ps.executeBatch();⑶ s'|^ 6/
conn.commit(); Fi^Q]9.@{
}catch(Exception e){ @.Pe.\Z
e.printStackTrace(); -Am~CM
} finally{ ]MXeWS(
try{ Z6I^HG{:
if(ps!=null) { bl;C=n
ps.clearParameters(); ngoAFb
ps.close(); e$+?l~
ps=null; O0i[GCtP5
} gLef6q{}
}catch(SQLException e){} { f@k2^
DBUtils.closeConnection(conn); ?`%)3gx|
} jP9)utEm6
} [EETx-
public long getLast(){ 8}kY^"*&X
return lastExecuteTime; I?mU _^no
} `:XrpD
public void run(){ sA u ;i
long now = System.currentTimeMillis(); 8s_'tw/{
if ((now - lastExecuteTime) > executeSep) { ovn)lIs
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^gpswhp
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//System.out.print(" now:"+now+"\n"); ."m2/Ks7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); hDJ84$eVZ
lastExecuteTime=now; E%vG#
executeUpdate(); _pv<_
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} R8lBhLs
else{ 45;{tS.z,B
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); vNJ!d
} ta-kqt!'
} jJF(*D
} i|5 K4Puu
//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 ^Fr82rJs
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类写好了,下面是在JSP中如下调用。 6R+m;'
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<% pZ,P_?
CountBean cb=new CountBean(); 4EiEE{9V
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); C=6 Vd
CountCache.add(cb); [p+6HF
out.print(CountCache.list.size()+"<br>"); e!67Na0X(
CountControl c=new CountControl(); p9[J9D3~
c.run(); > T,^n
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out.print(CountCache.list.size()+"<br>"); \?_eQKiZ3
%>