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: ixI fJ
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CountBean.java Fwv(J_'q
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/* p}R3AJ
* CountData.java qox31pnS
* %y}l^P5z
* Created on 2007年1月1日, 下午4:44 *L~88-V^
* Na2n4x!
* To change this template, choose Tools | Options and locate the template under (.54`[2+L
* the Source Creation and Management node. Right-click the template and choose 5Rec~&v
* Open. You can then make changes to the template in the Source Editor. Sej\Gt
*/ E;C=V2#>[
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package com.tot.count; Fl&Z}&5p
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/** Um\_G@
* A/{0J\pA
* @author dk4|*l-
*/ h2]gA_T`
public class CountBean {
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private String countType; ![#>{Q4i
int countId; Rt10:9Kz$
/** Creates a new instance of CountData */ 3"J85V%h]n
public CountBean() {} l\{{iAC]I
public void setCountType(String countTypes){ u4p){|x7s
this.countType=countTypes; v22ZwP
} p[lciWEW
public void setCountId(int countIds){ V57tn6>b
this.countId=countIds; 0"to]=
} nI6[y)j
public String getCountType(){ *ioVLt,:R
return countType; j9Y'HU5"
} &DgJu.
public int getCountId(){ qCaM]Y
return countId; SvD^'(
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} t)/:VImY
} ^-i<TJ
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CountCache.java '
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/* )dgooq
* CountCache.java 8f0Ytfhw
* 4?)-;Hx_X
* Created on 2007年1月1日, 下午5:01 t&99ZdE
* &;O)Dw
* To change this template, choose Tools | Options and locate the template under gr
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* the Source Creation and Management node. Right-click the template and choose ;3H#8x-
* Open. You can then make changes to the template in the Source Editor. p +>vX
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*/ zgh~P^Z
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package com.tot.count; ^sA"&Vdr^
import java.util.*; R8<'m
/** KDzTe9
* YZH&KGY
* @author D-IXO@x
*/ 0cBk/x^s
public class CountCache { X}s}E
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public static LinkedList list=new LinkedList(); Y +9OP
/** Creates a new instance of CountCache */ &^4 E )F
public CountCache() {} +P?^Yx0d
public static void add(CountBean cb){ u4UQMj|q
if(cb!=null){ )Cm7v@B
list.add(cb); 4Cdl^4(LT
} !{,
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} pNzSy"Y$
} IT\lkF2
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CountControl.java Q7-d]xJ^
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/* ;=[~2*8
* CountThread.java &:"[hU
* M)1?$'Aq
* Created on 2007年1月1日, 下午4:57 T8ftBIOi
* ^5yFb=2
* To change this template, choose Tools | Options and locate the template under lB
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* the Source Creation and Management node. Right-click the template and choose L~])?d
* Open. You can then make changes to the template in the Source Editor. 3\Ma)\>R\-
*/ [Q=NGHB1/
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package com.tot.count; |tkhsQ-;
import tot.db.DBUtils; *j0kb"#
import java.sql.*; LYv$U;*+
/** hD5G\TR.
* `Ko6;s#
* @author rcWr0q
*/ Jm l4EW7
public class CountControl{ (\=iKE4#
private static long lastExecuteTime=0;//上次更新时间 OYsG#
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 v)a$;P%
/** Creates a new instance of CountThread */ },G>+ s8h
public CountControl() {} qd7 86~
public synchronized void executeUpdate(){ $Jt+>.44
Connection conn=null; j5yxdjx9
PreparedStatement ps=null; 9(PQ7}
try{ k}yUD 0Y
conn = DBUtils.getConnection(); uS%Y$v
conn.setAutoCommit(false); `T]1u4^E
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); rfdT0xfcU
for(int i=0;i<CountCache.list.size();i++){ @}{~Ofs
CountBean cb=(CountBean)CountCache.list.getFirst(); vQ/&iAyut
CountCache.list.removeFirst(); E4nj*Lp~+
ps.setInt(1, cb.getCountId()); %j3*j
ps.executeUpdate();⑴ 8=%%C:
//ps.addBatch();⑵ DgQw9`WA
} i"{ \ >
//int [] counts = ps.executeBatch();⑶ ^Cs5A0xo#s
conn.commit(); oq<n5
}catch(Exception e){ &Jr~)o
e.printStackTrace(); `2M`;$~ 5
} finally{ )OAd[u<
try{ h* to%N
if(ps!=null) { AJ*FQo.U
ps.clearParameters(); AIR\>.~"i*
ps.close(); Q'ok%9q!p
ps=null; xgi/,Nk '
} fA]b'8
}catch(SQLException e){} )aOPR|+
DBUtils.closeConnection(conn); HktvUJ(Ii
} -|l^- Qf!
} -2dk8]KB]
public long getLast(){ <3;Sq~^
return lastExecuteTime; ) DzbJ}
} ,c%>M^d
public void run(){ 7n1@m_7O
long now = System.currentTimeMillis(); )K4A-9pC
if ((now - lastExecuteTime) > executeSep) { j(`L)/|O
//System.out.print("lastExecuteTime:"+lastExecuteTime); h7( R/R f
//System.out.print(" now:"+now+"\n"); p)$DpNL% p
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ZPT6
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lastExecuteTime=now; Kug_0+gI
executeUpdate(); 86s.qPB0
} "1P>,\Sjg
else{ )rTV}Hk
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); u49v,,WGw
} eN/o}<(e
} se)vi;J7 K
} q@i,$R
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 S9$* w!W
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类写好了,下面是在JSP中如下调用。 1Fado$#
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<% b`@aiXN)+
CountBean cb=new CountBean(); wX_s./#JJ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); P+m{hn~%
CountCache.add(cb); Hq{i-z+
out.print(CountCache.list.size()+"<br>"); w!0`JPu
CountControl c=new CountControl(); ZE ())W"
c.run(); wgK:^DP
out.print(CountCache.list.size()+"<br>"); 6w
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