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: YywiY).]@
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CountBean.java u#(&
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/* 0IZaf%zYc
* CountData.java A:|dY^,:?*
* c:#<g/-{wM
* Created on 2007年1月1日, 下午4:44 b#ga
* bVfFhfh*
* To change this template, choose Tools | Options and locate the template under yx5F]Z<M2
* the Source Creation and Management node. Right-click the template and choose b-*3]gB
* Open. You can then make changes to the template in the Source Editor. 6P,vGmR
*/ ]U[y3
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package com.tot.count; WFWQ;U{|
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/** Y~I$goT
* GMk\
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* @author _#[~?g`
*/ SCwAAE9s]
public class CountBean { RF3?q6j ,
private String countType; (EW<Ggi
int countId; 5>9KW7^L
/** Creates a new instance of CountData */ i4<&zj})
public CountBean() {} -,xCUG<g
public void setCountType(String countTypes){ :Y? L*
this.countType=countTypes; "ijpqI
} EY~b,MIL4
public void setCountId(int countIds){ $;O-1# ]
this.countId=countIds; #h,7dz.d
} eAqSY s!1
public String getCountType(){ Q?"o.T';
return countType; IZ){xI
} 99QMMup
public int getCountId(){ !LGnh
return countId; yf|,/{S
} fPXMp%T!
} \.0cA4)[$
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CountCache.java $H0diwl9R
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/* GCrIaZ
* CountCache.java 1zo0/<dk
* Xk2M.:3`
* Created on 2007年1月1日, 下午5:01 {?2jvv
* [^N8v;O
* To change this template, choose Tools | Options and locate the template under 4Cd#S9<ed
* the Source Creation and Management node. Right-click the template and choose w$5~'Cbi
* Open. You can then make changes to the template in the Source Editor. !v/j*'L<M}
*/ ]V*ku%L0
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package com.tot.count; 4}i2j
import java.util.*; SW94(4qo
/** LwPZR E#
* =J@M,mbHg
* @author bIvF5d>9#K
*/ >Q(+H-w
public class CountCache { ,(1n(FZ
public static LinkedList list=new LinkedList(); !yUn|v>&p
/** Creates a new instance of CountCache */ `
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public CountCache() {} CsJ38]=Mt
public static void add(CountBean cb){ 4Sj;38F
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if(cb!=null){ %:jVx
list.add(cb); 2X];zY
} W|~Jl7hs8Q
} ;HKb
} 4blw9x N
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CountControl.java )^Ha?;TS
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/* tQ:g#EqL9B
* CountThread.java tVAWc$3T
*
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3
* Created on 2007年1月1日, 下午4:57 h;q=<[h\
* m=saUhI*9
* To change this template, choose Tools | Options and locate the template under {"^LUw8fd
* the Source Creation and Management node. Right-click the template and choose 4jWzYuI&J
* Open. You can then make changes to the template in the Source Editor. s=[Tm}[
*/ uq/z.m
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package com.tot.count; ,^Cl?\9"
import tot.db.DBUtils; +2DzX/3
import java.sql.*; o+NPe36
/** 73n|G/9n[
* |iGfX,C|
* @author >"OwdAvX
*/ 1q?b?.
public class CountControl{ ;8|D4+
private static long lastExecuteTime=0;//上次更新时间 sl5y1W/]]
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 -K"" 4SC2
/** Creates a new instance of CountThread */ y_s^dQe
public CountControl() {} <N4)X"s
public synchronized void executeUpdate(){ mYU7b8x_
Connection conn=null; v?BVUH>#9
PreparedStatement ps=null; zC@ ziH>{]
try{ 4t C-msTf
conn = DBUtils.getConnection(); A-=B#U F
conn.setAutoCommit(false); P^lzl:|
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); /mi9q
for(int i=0;i<CountCache.list.size();i++){ i8h(b2odQ
CountBean cb=(CountBean)CountCache.list.getFirst(); r>>4)<C7J
CountCache.list.removeFirst(); U~;Rzoe)q*
ps.setInt(1, cb.getCountId()); 0Q>yv;M
ps.executeUpdate();⑴ f *Xum[
//ps.addBatch();⑵ oVD)Fb%[i9
} u~uR:E%'C
//int [] counts = ps.executeBatch();⑶ z%4E~u10
conn.commit(); Sckt gp8
}catch(Exception e){ DH@]d0N
e.printStackTrace(); >A]U.C
} finally{
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try{ 3SI~?&HU!/
if(ps!=null) { +hUS
sR&
ps.clearParameters(); .5S< G)Ja
ps.close(); rE&`G[(b
ps=null; T<jo@z1UL
} P#0U[`ltK
}catch(SQLException e){} Moldv
x=M
DBUtils.closeConnection(conn); P!6v0ezN
} (0wQ [(
} "e3T;M+
public long getLast(){ S=
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return lastExecuteTime; ?Aq
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} jfLkp>2E'
public void run(){ &Zzd6[G+
long now = System.currentTimeMillis(); gv6}GE
if ((now - lastExecuteTime) > executeSep) { Zb \E!>V
//System.out.print("lastExecuteTime:"+lastExecuteTime); vU4Gw4
//System.out.print(" now:"+now+"\n"); wsfN \6e
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zL^`r)H
lastExecuteTime=now; Ky r3)1#J
executeUpdate(); ~BUzyc%
} 6~oo.6bA
else{ W[$GB_A)
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); a>05Yxw
} :
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} +i\ +bR
} q7z;b A
//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 7Gos-_s
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类写好了,下面是在JSP中如下调用。 I^u$H&
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<% A"Prgf
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CountBean cb=new CountBean(); Fm{/&U^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 4s:S_Dw
CountCache.add(cb); O<*l"fw3
out.print(CountCache.list.size()+"<br>"); b`9J1p.;
CountControl c=new CountControl(); ,k9@%{4 l
c.run(); ,mHQ
out.print(CountCache.list.size()+"<br>"); j;BMuLTm1
%>