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: 0p\Kf(|E*6
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CountBean.java =">0\#
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/* WaE%g
* CountData.java #!r>3W&
* 4v#s!W
* Created on 2007年1月1日, 下午4:44 _m%Ab3iT~
* T@n};,SQ
* To change this template, choose Tools | Options and locate the template under Ffd;aZ4n
* the Source Creation and Management node. Right-click the template and choose ,z+n@sUR:
* Open. You can then make changes to the template in the Source Editor. 8>X] wA6q
*/ 7!6v4ZA
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package com.tot.count; fA ),^
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/** ~D/1U)kt
* ~P*{%= a
* @author Ir5E*op7D
*/ SUsdX[byb
public class CountBean { A3.pz6iT>
private String countType; @CC
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int countId; (/i|3 P
/** Creates a new instance of CountData */ un)PW&~E
public CountBean() {} YH{n
public void setCountType(String countTypes){ W"tGCnd
this.countType=countTypes; )k4&S{=
} 2>Qy*
public void setCountId(int countIds){ D28>e
this.countId=countIds; (:}}p}u
} $3eoZ1q'U-
public String getCountType(){ X*&Thmee
return countType; (/!zHq
} Z[1|('
public int getCountId(){ )X8N|W>vh
return countId; Rq|]KAN
} U8<C4
} yFTN/MFt
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CountCache.java I(Vg
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/* )C rsm&
* CountCache.java C879eeJ
* Na+h+wD.D
* Created on 2007年1月1日, 下午5:01 c\&;Xr
* Q
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* To change this template, choose Tools | Options and locate the template under y6x./1Nb}<
* the Source Creation and Management node. Right-click the template and choose *X ;ch55\
* Open. You can then make changes to the template in the Source Editor. MI(;0
*/ ,v#n\LD`
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package com.tot.count; iA[o;D#
import java.util.*; ^u1Nbo
/** jZ:/d!$S
* (@qS
* @author e6
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*/ !H{>c@i
public class CountCache { @!O(%0
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public static LinkedList list=new LinkedList(); u86PTp+
/** Creates a new instance of CountCache */ \8s:I+[HH
public CountCache() {} ~TeOl|!lE+
public static void add(CountBean cb){ 5MD'AP:
if(cb!=null){ kE8s])Z,+
list.add(cb); yWE\)]9
} ZkQ6~cM
} ?%Tx%
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} R[S1<m;
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CountControl.java x?0K'
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/* yjH'<
* CountThread.java #7}M\\$M
* !MOsP<2
* Created on 2007年1月1日, 下午4:57 p@uHzu7
* hsS&|7Pt
* To change this template, choose Tools | Options and locate the template under KG9-ac
* the Source Creation and Management node. Right-click the template and choose 9y;}B
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* Open. You can then make changes to the template in the Source Editor. 6w{_+=T
*/ ~gGkw#
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package com.tot.count; o$Nhx_F
import tot.db.DBUtils; b=pk;'-
import java.sql.*; VwZ~ntk
/** K[0z$T\
* i8-Y,&>V
* @author _@[W[=|H
*/ -PGxG 8S
public class CountControl{ [u2t1^#Ol
private static long lastExecuteTime=0;//上次更新时间 !K}W.yv,
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 As,e.V5!
/** Creates a new instance of CountThread */ 4;CI<&S
public CountControl() {} JJSE@$",\
public synchronized void executeUpdate(){ \4G9YK-N>
Connection conn=null; eI2HTFyT
PreparedStatement ps=null; " M?dU^U^
try{ 0'$67pY
conn = DBUtils.getConnection(); ?Z?(ky!
conn.setAutoCommit(false); 5|K[WvG@Co
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 2y;vX|lX]
for(int i=0;i<CountCache.list.size();i++){ PQSmBTs.
CountBean cb=(CountBean)CountCache.list.getFirst(); >c<xy>N
CountCache.list.removeFirst(); <,n:w[+!`P
ps.setInt(1, cb.getCountId()); 6o3#<ap<
ps.executeUpdate();⑴ FjtS
//ps.addBatch();⑵ w)@Wug
} 0+@:f^3]!
//int [] counts = ps.executeBatch();⑶ }8aqSD<:
conn.commit(); M."/"hV`-
}catch(Exception e){ >A-{/"p#
e.printStackTrace(); w(S~}'Sg*P
} finally{ 2 (l0Lq*
try{ 2z;3NUL$n
if(ps!=null) { {2P18&=
ps.clearParameters(); IjRUr \ l
ps.close(); qAH^BrJ
ps=null; !ae?EJm"
} W4 d32+V
}catch(SQLException e){} #!UJY%c~
DBUtils.closeConnection(conn); w->Y92q]
} Z Se30Rl\
} *P`wuXn}
public long getLast(){ $o5i15Oy.
return lastExecuteTime; X5[t6q!
} ki@C}T5
public void run(){ HB5-B XBU
long now = System.currentTimeMillis(); .qZz'Eq[
if ((now - lastExecuteTime) > executeSep) { kG!hqj
//System.out.print("lastExecuteTime:"+lastExecuteTime); Y]0c%Fd
//System.out.print(" now:"+now+"\n"); #.HnO_sK_
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 'hBnV xd&
lastExecuteTime=now; $u~ui@kB
executeUpdate(); M3@qhEf?vk
} {._'Q[
else{ q 9xA.*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ly*v|(S&
} #vyf*jPr
} [ R+M .5
} jwE=
//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 %?gG-R
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类写好了,下面是在JSP中如下调用。 q&v~9~^}d
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<% K\U`gTGc
CountBean cb=new CountBean(); Z@Q*An
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |*g#7YL
CountCache.add(cb); Bt@?l]Y
out.print(CountCache.list.size()+"<br>"); N}B&(dJ
CountControl c=new CountControl();
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c.run(); ;u'VR}4ph
out.print(CountCache.list.size()+"<br>"); 0/f|ZH ~!
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