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: FrRUAoFO
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CountBean.java PTQN.[bBh
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/* DLq'V.M:
* CountData.java .5~3D97X&
* Eg4&D4TGp
* Created on 2007年1月1日, 下午4:44 Q*f0YjH!
* Ix@nRc'
* To change this template, choose Tools | Options and locate the template under ~1Ffu x
* the Source Creation and Management node. Right-click the template and choose "-HWw?rx/
* Open. You can then make changes to the template in the Source Editor. jlyuu
*/ 4y)6!p
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package com.tot.count; H.Z<T{y;
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/** Yi`DRkp]3
* do.XMdit
* @author |*~SR.[`
*/ Ln4Dq[M
public class CountBean { kK&AK2
private String countType; 1#zD7b~
int countId; 1O2V!?P
/** Creates a new instance of CountData */ U@}r?!)"f
public CountBean() {} |41~U\
public void setCountType(String countTypes){ @E> rqI;`
this.countType=countTypes; +wGvYr
} n&Q0V.
public void setCountId(int countIds){ a0k/R<4
this.countId=countIds; q:wz!~(>
} (AG((eV
public String getCountType(){ {(d 6of`C_
return countType; #A~7rH%hi
} )ItW}1[I
public int getCountId(){ nx!+:P ,
return countId; 7<*g'6JG[
} |lIgvHgg
} H:q;IYE+a
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CountCache.java VTO92Eo
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/* 0,cU^HMA
* CountCache.java B}I9+/|{
* [t?:CgI)E
* Created on 2007年1月1日, 下午5:01 9
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* .;dI&0Z
* To change this template, choose Tools | Options and locate the template under /i"1e:cK
* the Source Creation and Management node. Right-click the template and choose y=}o|/5"
* Open. You can then make changes to the template in the Source Editor. Pp;OkI``[
*/ MdnapxuS
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package com.tot.count; 0c&DSL}6
import java.util.*; ,y)V5
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/** T|--ZRYn
* F~GIfJU
* @author AI$\wp#aw
*/ *b`1+~p_2
public class CountCache { &<(&u`S
public static LinkedList list=new LinkedList(); 5hDm[*83
/** Creates a new instance of CountCache */ bW GMgC
public CountCache() {} Rf!$n7& \
public static void add(CountBean cb){ ,}^FV~
if(cb!=null){ Rz<'&Z>;
list.add(cb); p3IhK>
} ;YrmT9Jx6
} fKkS_c
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} fTGVG
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CountControl.java 4SIS#m
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/* +@+*sVb
* CountThread.java );xTl6Y9
* gZL,xX
* Created on 2007年1月1日, 下午4:57 F{eI[A
* VP }To
* To change this template, choose Tools | Options and locate the template under dlDO?T
* the Source Creation and Management node. Right-click the template and choose [n$6T
* Open. You can then make changes to the template in the Source Editor. &3 x
[0DV
*/ O~5*X f
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package com.tot.count; r:t3Kf`+E-
import tot.db.DBUtils; > q8)~
import java.sql.*; C:vVFU|4
/** |cl*wFm|3
* /b."d\
* @author r_Pi)MPc
*/ C!|Yz=e
public class CountControl{ 5?>ES*
private static long lastExecuteTime=0;//上次更新时间 >UXNR`?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `>HrO}x^
/** Creates a new instance of CountThread */ kq>I?wg
public CountControl() {} I$ ?.9&.&
public synchronized void executeUpdate(){ q]Af I(
Connection conn=null; V?n=yg
PreparedStatement ps=null; 7J|nqr`>t
try{ ]4,eCT
conn = DBUtils.getConnection(); Ime"}*9
conn.setAutoCommit(false); PebyH"M(
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ]9}^}U1."
for(int i=0;i<CountCache.list.size();i++){ "|/Q5*L
CountBean cb=(CountBean)CountCache.list.getFirst(); a6 "-,Kg
CountCache.list.removeFirst(); dlioa Yc
ps.setInt(1, cb.getCountId()); d*LW32B@
ps.executeUpdate();⑴ zCmx 1Djz
//ps.addBatch();⑵ ,b t
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} rb]?"lizi
//int [] counts = ps.executeBatch();⑶ (J.k\d
conn.commit(); x-~=@oiv
}catch(Exception e){ O_v*,L!
e.printStackTrace(); 8-x)8B
} finally{ B|r'
try{ SL`nt
if(ps!=null) { Lv<vMIr
ps.clearParameters(); C/q!!
ps.close(); 3 ]pHc)p!.
ps=null; wT +\:y
} #l!nBY ~
}catch(SQLException e){} pzeCdHF
DBUtils.closeConnection(conn); JD]uDuE
} z2 mjm
} `r&]Ydu:
public long getLast(){ vywpX^KPv
return lastExecuteTime; 1/J6<FVq
} j7J'd?l
public void run(){ )h0b}HMW)
long now = System.currentTimeMillis(); +77B656
if ((now - lastExecuteTime) > executeSep) { b[ ~-b
//System.out.print("lastExecuteTime:"+lastExecuteTime); /])P{"v$^
//System.out.print(" now:"+now+"\n"); U.N?cKv
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); *rA]q' jM
lastExecuteTime=now; ]$I}r=
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executeUpdate(); \%&eDE 0
} @DSKa`
else{ !1/F71l DX
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); +9B .}t#
} ]l,,en5V
} k +Cwnp
} &"^U=f@v
//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 ZKai*q4?
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类写好了,下面是在JSP中如下调用。 4B)%I`
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<% \85~~v@
CountBean cb=new CountBean(); 664D5f#EJ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /|isRh|
CountCache.add(cb); \J(kM,ZJ
out.print(CountCache.list.size()+"<br>"); 9T0g%&
CountControl c=new CountControl(); `yO'-(@"gY
c.run(); BO.Db``
out.print(CountCache.list.size()+"<br>"); >~_)2_j
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