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: &3u*
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CountBean.java A;2?!i#f
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/* DVpqm6$Q
* CountData.java n'M}6XUw
* 9KAXc(-
* Created on 2007年1月1日, 下午4:44 u_:"
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* p=Vm{i7
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose p&ZD1qa
* Open. You can then make changes to the template in the Source Editor. cT.1oaAM0
*/ T}4RlIZF
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package com.tot.count; ;PLby]=O
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/** a&y%|Gs^f
* ql8CgL
* @author L0uN|?}
*/ >TtkG|/U-T
public class CountBean { 8G{} r
private String countType; meIY00
int countId; 5ue{&z
@T
/** Creates a new instance of CountData */ (<3'LhFII
public CountBean() {} V1"+4&R^T_
public void setCountType(String countTypes){ ]1p&*xX:Bj
this.countType=countTypes; [qid4S~r,&
} ]LP&v3
public void setCountId(int countIds){ \9D
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this.countId=countIds; KeXQ'.x5O
} jQ7RH/?_
public String getCountType(){ 8 Z#)Xb4
return countType; #<!oA1MH4
} 1Rwk}wL
public int getCountId(){ B23R9.FK
return countId; |yQ3H)qB#
} <EpP;
} *4+;Ey
~":?})
CountCache.java rF
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/* LI(Wu6*Y
* CountCache.java @gs
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* +hKQha!*
* Created on 2007年1月1日, 下午5:01 J^1w& 40
* {]|};E[}m
* To change this template, choose Tools | Options and locate the template under &a-:ZA@
* the Source Creation and Management node. Right-click the template and choose )2FS9h.t
* Open. You can then make changes to the template in the Source Editor. I_eYTy-a`1
*/ })ss.
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package com.tot.count; )LH nDx
import java.util.*; xB
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/** !XgkK k
* +mV4Ty
* @author spn1Ji
*/ v#D9yttO{
public class CountCache { .F}ZP0THnZ
public static LinkedList list=new LinkedList(); ,uuQj]Dac+
/** Creates a new instance of CountCache */ QJ pUk%Wj
public CountCache() {} D<Ads
public static void add(CountBean cb){ Yc\;`C
if(cb!=null){ Z.VVY\
list.add(cb); {P-KU RQ
} R-hqaEB
} sa*]q~a
} B||^sRMX
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CountControl.java E
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/* vZ$uD,@;.
* CountThread.java [#uX{!q'
* (zye
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* Created on 2007年1月1日, 下午4:57 MT;<\T
* ToDN^qE+
* To change this template, choose Tools | Options and locate the template under fm:/}7s
* the Source Creation and Management node. Right-click the template and choose Lj({
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* Open. You can then make changes to the template in the Source Editor. %E~4 Ur
*/ `h :&H,N
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package com.tot.count; j[) i>Qw
import tot.db.DBUtils; #Rjm3#gc
import java.sql.*; xzIs,i}U
/** A3yVT8
* _W tSZmW?
* @author rb&^ ei9B
*/ 5K{(V^88F
public class CountControl{ A
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private static long lastExecuteTime=0;//上次更新时间 T(7
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 kzgHp,;R{
/** Creates a new instance of CountThread */ %|oY8;0|A>
public CountControl() {} #j iQa"
public synchronized void executeUpdate(){ y.w/7iw:
Connection conn=null; D@5&xd_@4
PreparedStatement ps=null; +;U}SR<
try{ %NX
conn = DBUtils.getConnection(); U:gE:t f
conn.setAutoCommit(false); ?!Rlp/
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Lo7R^>
for(int i=0;i<CountCache.list.size();i++){ )nQpO"+M
CountBean cb=(CountBean)CountCache.list.getFirst(); )I.[@#-
CountCache.list.removeFirst(); y9Yh%M(
ps.setInt(1, cb.getCountId()); z/6kxV 89
ps.executeUpdate();⑴ 6>Lr
//ps.addBatch();⑵ S"5</*
} ^[\F uSL
//int [] counts = ps.executeBatch();⑶ -Ww'wH'2
conn.commit(); 4K[U*-\"
}catch(Exception e){ fCO!M1 t
e.printStackTrace(); ~?[%uGI0h
} finally{ oKA8)~Xqou
try{ NrNbNFfo
if(ps!=null) { .OXvv _?<
ps.clearParameters(); 1UyI.U]
ps.close(); E"pq ZP =
ps=null; + :iNoDz
} w<-CKM3qe
}catch(SQLException e){} t}_qtO7>
DBUtils.closeConnection(conn); v)okVyv
} RUYwDtC
} B07(15y]
public long getLast(){ |DwI%%0(F
return lastExecuteTime; 0)yvyQ5
} k3}ymhUf
public void run(){ h+t{z"Ic=
long now = System.currentTimeMillis(); + [|2k(U
if ((now - lastExecuteTime) > executeSep) { y5BNHweaRb
//System.out.print("lastExecuteTime:"+lastExecuteTime); ~O
65=8
//System.out.print(" now:"+now+"\n");
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); )/Ee#)z*
lastExecuteTime=now; MftX~+
executeUpdate(); {-7];e
} w[~$.FM/
else{ @m1v B!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); z<sf}6q
} ^r}^-
} -81usu&NH
} Z[ZqQ` 7N
//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 O}Fp\"
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类写好了,下面是在JSP中如下调用。 Beiz*2-}a
aVM@^n
<% 0p*(<8D}
CountBean cb=new CountBean(); kJZBQ<^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 2oGl"3/p
CountCache.add(cb); _F;(#D
out.print(CountCache.list.size()+"<br>"); 1Xu\Tm\Ux
CountControl c=new CountControl(); !3kyPoq+
c.run(); 6f\0YU<C&
out.print(CountCache.list.size()+"<br>"); VkRvmKYl
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