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: y-93 >Y
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CountBean.java S]3t{s#JW7
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/* L= fz:H
* CountData.java Y\len
* bCF"4KXK
* Created on 2007年1月1日, 下午4:44 [g:ZIl4p\P
* #xS8
* To change this template, choose Tools | Options and locate the template under Bp`?inKBOd
* the Source Creation and Management node. Right-click the template and choose c6;tbL
* Open. You can then make changes to the template in the Source Editor. Ii/#cdgF
*/ ,tZWPF-
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package com.tot.count; MGd 7Ont
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/** .R` {.~_{!
* eFUJASc
* @author 2#:h.8
*/ 7W6tz\Y
public class CountBean { DDT)l+: XP
private String countType; R;gN^Yjk:
int countId; 0S0 ?\r
/** Creates a new instance of CountData */ 5uuZ t0V\
public CountBean() {} D}wM$B@S
public void setCountType(String countTypes){ 8M;VX3X
this.countType=countTypes; G _{x)@
} p*8LS7UT
public void setCountId(int countIds){ V6Y:l9
this.countId=countIds; |~Hlv^6H
} w^?uBeqR
public String getCountType(){ |"vUC/R2&
return countType; N246RV1W
} xZ }1dq8
public int getCountId(){ vl8Ums} +
return countId; SNB>
} J)iy6{0"
} WhsTKy&E
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CountCache.java q"@Y2lhD!
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/* `w1|(Sk$h
* CountCache.java vd>X4e^j
* ]?p&sI4
* Created on 2007年1月1日, 下午5:01 G%w hOIFRq
* 0!YB.=\{_q
* To change this template, choose Tools | Options and locate the template under _4VF>#b
* the Source Creation and Management node. Right-click the template and choose G/Nb@pAy[
* Open. You can then make changes to the template in the Source Editor. ixZ w;+h
*/ q[#2`
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package com.tot.count; 8*;88vW"2
import java.util.*; sG`:mc~0
/** /pZ]:.A
* \-Mzs 0R
* @author #wL}4VN
*/ V8w!yc
public class CountCache { 1H{M0e
public static LinkedList list=new LinkedList(); 6H,n?[zTt
/** Creates a new instance of CountCache */ A\9QgM
public CountCache() {} R87-L*9B^0
public static void add(CountBean cb){ M/XxiF
if(cb!=null){ !j,LS$tPu
list.add(cb); s)ymm7?
} 7{
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} 3>Ts7
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} 2?hc94
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CountControl.java M[N$N`9
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/* ]p/f@j?LU
* CountThread.java (5y+g?9d;
* |[/[*hDZ9
* Created on 2007年1月1日, 下午4:57 Z&gM7Zo8
* L|Zja*
* To change this template, choose Tools | Options and locate the template under '`$z!rA
* the Source Creation and Management node. Right-click the template and choose c=iv\hn
* Open. You can then make changes to the template in the Source Editor. D3s]49j)
*/ hce *G@b
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package com.tot.count; x}t,v.:
import tot.db.DBUtils; ^W|B Xxo
import java.sql.*; RHc63b\
/** w,fA-*bZ 0
* [;3` Aw
* @author jdsN ZV
*/ =c
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public class CountControl{ Ww&~ZZZ {
private static long lastExecuteTime=0;//上次更新时间 8.4 1EKr2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !PX`sIkT
/** Creates a new instance of CountThread */ bM[!E 8dF
public CountControl() {} <u2rb6
public synchronized void executeUpdate(){ `wRQ-<Y
Connection conn=null; ^a&-GhX;
PreparedStatement ps=null; #jAlmxN
try{ &eYnO~$!
conn = DBUtils.getConnection(); O(U'G|
conn.setAutoCommit(false); ZSCZt&2v
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); tJ>|t hk
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); ?;Ck]l#5ys
CountCache.list.removeFirst(); Gq_rZo(@
ps.setInt(1, cb.getCountId()); -F.A1{l[.
ps.executeUpdate();⑴ '|mVY; i[
//ps.addBatch();⑵ UX3
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} {[~cQgCI
//int [] counts = ps.executeBatch();⑶ 0F$;]zg
conn.commit(); %$K2$dq5
}catch(Exception e){
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e.printStackTrace(); 34ij5bko_)
} finally{ Ve,h]/G
try{ acd8?>%[
if(ps!=null) { i;4|UeUl
ps.clearParameters(); 2%Bq[SMuN
ps.close(); +X)n} jh
ps=null; d1YE$
} HAa2q=
}catch(SQLException e){} oxkA+}^j8M
DBUtils.closeConnection(conn); !QK~l
} *7.EL`8
} 5ve4 u
public long getLast(){ <xOv0B
return lastExecuteTime; T~B'- >O
} ^fVLM>p <;
public void run(){ N|cWTbi
long now = System.currentTimeMillis(); >_3+s~
if ((now - lastExecuteTime) > executeSep) { K:Mm?28s
//System.out.print("lastExecuteTime:"+lastExecuteTime); P|mV((/m4
//System.out.print(" now:"+now+"\n"); 2
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "vVL52HwB
lastExecuteTime=now; :2#8\7IU^'
executeUpdate(); MRzrZZ%LQ
} Q"UWh~
else{ ^6*LuXPv
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); HZ$q`e
} ;4DqtR"7Y
} 6- H81y3
} |BrD:+
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 oNV5su
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类写好了,下面是在JSP中如下调用。 Z]-C,8MM
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<% #$trC)? ~q
CountBean cb=new CountBean(); o(iv=(o
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); XEd|<+P1
CountCache.add(cb); @Y2"=QVt
out.print(CountCache.list.size()+"<br>"); JN;92|x
CountControl c=new CountControl(); V. sIiE
c.run(); ^<L;"jl%
out.print(CountCache.list.size()+"<br>"); 1o5DQ'~n
%>