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: m@<,bZkl
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CountBean.java uYeb RCdR
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/* 4(htdn6 \
* CountData.java zYM2`(Z
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* qq!ZYWy2
* Created on 2007年1月1日, 下午4:44 wp~}1]g
* l=xG<)Okb
* To change this template, choose Tools | Options and locate the template under c7+6[y DVE
* the Source Creation and Management node. Right-click the template and choose 7NJl+*u
* Open. You can then make changes to the template in the Source Editor. ll5;09
*/ \8#[AD*@s2
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package com.tot.count; <Ch9"1f3,
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/** F(1E@xs
* S<(i /5Z+
* @author d\qszYP[
*/ pq0Z<b;2
public class CountBean { .+>fD0fW7Y
private String countType; { 5 r]G
int countId; /'8%=$2Kw
/** Creates a new instance of CountData */ 3\Amj}RJ
public CountBean() {} iJOoO"Ai
public void setCountType(String countTypes){ 5%D`y|
this.countType=countTypes; yPmo1|'X>d
} t5 >ma:^j
public void setCountId(int countIds){ Ju>QQOxi|
this.countId=countIds; dkg`T#}
} 1a9' *[
public String getCountType(){ [`tOhL
return countType; 8@vq.z}
} :#vA5kC
public int getCountId(){ Vw;iE=L
return countId; <
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} PoZ$3V$(Lz
} !9gpuS[
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CountCache.java %x#S?GMV<
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/* O4`.ohAZ
* CountCache.java Zs^zD;zU
* ]+G\1SN~
* Created on 2007年1月1日, 下午5:01 ]|F`;} 7
* #_\**%,<
* To change this template, choose Tools | Options and locate the template under @mw1__?
* the Source Creation and Management node. Right-click the template and choose n%h009-5
* Open. You can then make changes to the template in the Source Editor. %o9mG<.T
*/ |j"C52Q
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package com.tot.count; kPOk.F%)
import java.util.*; HpbwW=;V
/** oBmv^=cH
* mmwc'-jU:
* @author &H+ wzx<
*/ o?O ZsA
public class CountCache { I!F&8B+|
public static LinkedList list=new LinkedList(); s]yZ<uA
/** Creates a new instance of CountCache */ R:P),
public CountCache() {} 4grV2xtX
public static void add(CountBean cb){ 3K(/=
if(cb!=null){ \aSc2Ml]3n
list.add(cb);
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} bZSt<cH3
} =?L16mu1&
} =WN8><K!
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CountControl.java oTk\r$4eb
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/* n<EIu
* CountThread.java Af]BR_-
* E5gt_,j>
* Created on 2007年1月1日, 下午4:57 1$))@K-I
* DB"z93Mr<K
* To change this template, choose Tools | Options and locate the template under Z3zD4-p$_
* the Source Creation and Management node. Right-click the template and choose LP7jCt
* Open. You can then make changes to the template in the Source Editor. =WF@S1
*/ `?&C5*P
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package com.tot.count; c 9gm%
import tot.db.DBUtils; Lniz>gSc
import java.sql.*; ;U0w<>4L
/** V#599-
* 0XE6Hw
* @author O 8 l`1
*/ Y)8 Py1}
public class CountControl{ Fbotn(\h@
private static long lastExecuteTime=0;//上次更新时间 %N\45nYU:
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 _ y'g11 \
/** Creates a new instance of CountThread */ ;|= 5)KE
public CountControl() {} 5:+x7Ed
public synchronized void executeUpdate(){ "kt7m
Connection conn=null; =H-BsX?P
PreparedStatement ps=null; Yk{4 3yw
try{ mr>E'd.'
conn = DBUtils.getConnection(); r"L:Mu
conn.setAutoCommit(false); 1"A"AMZf
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); H(?+-72KX
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); 5!i\S[:
CountCache.list.removeFirst(); =f=>buD
ps.setInt(1, cb.getCountId()); 4D.h~X4
ps.executeUpdate();⑴ ,~=+]9t
//ps.addBatch();⑵ ZdhA:}~^E
} QeQwmI
//int [] counts = ps.executeBatch();⑶ 4,`t9f^:
conn.commit(); j0cB#M44
}catch(Exception e){ +IGSOWL
e.printStackTrace(); CW@EQ3y0
} finally{ ;[C_ho
try{ KVC18"|f
if(ps!=null) { aB&a#^5CI
ps.clearParameters(); 9nd,8Nji
ps.close(); N+UBXhh
ps=null; oj6=.
} )CH\]>-FO
}catch(SQLException e){} 7CU<R9Kl
DBUtils.closeConnection(conn); 6C_H0a/h&
} d^Cv9%X
} &x.5TDB>%
public long getLast(){ o
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return lastExecuteTime; ^6UE/4x!y
} pmUC4=&e
public void run(){ &)Vuh=
long now = System.currentTimeMillis(); T~lHm
if ((now - lastExecuteTime) > executeSep) { _y [B/C,q
//System.out.print("lastExecuteTime:"+lastExecuteTime); #cl|5jm+m#
//System.out.print(" now:"+now+"\n"); IjPtJwW`A
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); QF.M%she+
lastExecuteTime=now; q\s>Oe6$
executeUpdate(); 1N.weey}W
} 27JZwlzZ
else{ i:R_g]
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0;5qo~1
} utdus:B#0
} 0d,&)
} ,PWMl[X
//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 0VgsV;
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类写好了,下面是在JSP中如下调用。 |'k7 ;UW
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<% ]D>\Z(b
CountBean cb=new CountBean(); x50ZwV&j
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 78'3&,+si
CountCache.add(cb); N,ihQB5
out.print(CountCache.list.size()+"<br>"); f2P2wt.$
CountControl c=new CountControl(); n~yhX%=_Du
c.run(); `g'9)Xf4KT
out.print(CountCache.list.size()+"<br>"); b9l%5a
%>