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: %+OPas8C
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CountBean.java DuC u6j
@OL3&R
/* MsiC!j.-
* CountData.java Qre&N_
* tZ{q\+h
* Created on 2007年1月1日, 下午4:44 #p9z#kin
* MH~qfH>K
* To change this template, choose Tools | Options and locate the template under AZ Lt'9UD
* the Source Creation and Management node. Right-click the template and choose V/[,1W[B
* Open. You can then make changes to the template in the Source Editor. J$ih|nP
*/ +`vZg^_c`
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package com.tot.count; /
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/** D@vvy6>~s
* ';L^mxh
* @author LyPBFo[?
*/ ?Dp^dR
public class CountBean {
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private String countType; RlPByG5K
int countId; co%_~xO
/** Creates a new instance of CountData */ arH\QPaka'
public CountBean() {} J,M5<s[Xqt
public void setCountType(String countTypes){ oP`M\KXau
this.countType=countTypes; o%JIJ7M
} (w:ACJ[[
public void setCountId(int countIds){ O?J:+L(
this.countId=countIds; M{kh=b)V
} 2]3Jb{8FI>
public String getCountType(){ JGNxJ S<]
return countType; pxnUe1=
} 7;-i_&vws
public int getCountId(){ 5nIlG
return countId; qO3BQ]UF
} ^E?V+3mV
} 4 AmF^H
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CountCache.java %[CM;|?B4
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/* =X'7V}Q}
* CountCache.java w3cK:
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* rxk{Li<9
* Created on 2007年1月1日, 下午5:01 \osQwGPV
* :Ty*i
* To change this template, choose Tools | Options and locate the template under +&8Ud8Q
* the Source Creation and Management node. Right-click the template and choose :\;uJ5
* Open. You can then make changes to the template in the Source Editor. ->9xw
*/ "@?kxRn!
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package com.tot.count; 8t
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import java.util.*; A|OC?NZY
/** b1^Yxe#L
* ^nZ2p$
* @author ~TR|Pv
*/ {hP&P
public class CountCache { M{RZ-)IC
public static LinkedList list=new LinkedList(); ?
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/** Creates a new instance of CountCache */ q;~>h
public CountCache() {} +((31l
public static void add(CountBean cb){ Yf`.Cq_:
if(cb!=null){ s3!LR2qiF
list.add(cb); G6bg ~V5Q:
} R*fR?
} myX0<j3G5
} j;'Wf[V
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CountControl.java X[Gk!dr#
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/* [t)i\ }V
* CountThread.java F76h
* _VJwC|
* Created on 2007年1月1日, 下午4:57 oT{yttSNo
* 9yAu<a
* To change this template, choose Tools | Options and locate the template under 1Sk6[h'CL
* the Source Creation and Management node. Right-click the template and choose Z*3}L
* Open. You can then make changes to the template in the Source Editor. 0!
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*/ 80>!qG
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package com.tot.count; $s!meg@s
import tot.db.DBUtils; 7V``f:#d
import java.sql.*; FQ1oqqr
/** *lF%8k"Al
* .g?,:$`0D?
* @author !_!b\
*/ C>VZf,JE1
public class CountControl{ C
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private static long lastExecuteTime=0;//上次更新时间 o@;_(knb
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Y &+/[[
/** Creates a new instance of CountThread */ *lO+^\HXD
public CountControl() {} TBT*j&!L
public synchronized void executeUpdate(){ WfO$q^'?DP
Connection conn=null; CxQ,yd;>
PreparedStatement ps=null; !\4FIs&Qv
try{ Pk_{{Z(1o
conn = DBUtils.getConnection(); J :(\o=5 5
conn.setAutoCommit(false); FWN%JCOj@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 8QBL:7<
for(int i=0;i<CountCache.list.size();i++){ MoHvXp;X
CountBean cb=(CountBean)CountCache.list.getFirst(); ') y~d
CountCache.list.removeFirst(); )KQum`pO
ps.setInt(1, cb.getCountId()); ~ riw7"
ps.executeUpdate();⑴ Ih"Ol(W
//ps.addBatch();⑵ - Sgp,"a
} e1Hx"7ew_
//int [] counts = ps.executeBatch();⑶ K a|\gl;V
conn.commit(); @1Lc`;Wd
}catch(Exception e){ >f8,YisH
e.printStackTrace(); !2I wuru
} finally{ ?\r3
_
try{ }`FPe
if(ps!=null) { ~-i?=
ps.clearParameters(); *4y r7~S5
ps.close(); tpK4 gjf
ps=null; #ySx$WT;
} D<6kAGE
}catch(SQLException e){} #::vMnT
DBUtils.closeConnection(conn); hZJqo + s
} "r+<=JU>OV
} 1X.1t^HH:
public long getLast(){ J)NpG9iN
return lastExecuteTime; HArYL}l
} o-=lH tR
public void run(){ )>p6h]]a
long now = System.currentTimeMillis(); >FNt*tX<0
if ((now - lastExecuteTime) > executeSep) { }iAi`_\0;
//System.out.print("lastExecuteTime:"+lastExecuteTime); ~T9[\nU\
//System.out.print(" now:"+now+"\n"); itvdzPO
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); KZNyp%q
lastExecuteTime=now; k({8C`&tK/
executeUpdate(); YfKty0
} pC8i&_A
else{ UMaKvr-C&
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); KW<CU'
} Um<vsR
} -Ma"V
} tEs$+b
//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 ZeZwzH)BD
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类写好了,下面是在JSP中如下调用。 ")OLmkC
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<% ]"6<"1)
CountBean cb=new CountBean(); gId+hxFa:r
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }Jfo(j
CountCache.add(cb); R&0l4g-4>
out.print(CountCache.list.size()+"<br>"); {5JXg9um
CountControl c=new CountControl(); C-Z,L#
c.run(); }1dh/Cc`
out.print(CountCache.list.size()+"<br>"); *93 N0m4Rl
%>