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: s
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CountBean.java M?nnpO
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/* iZSjT"l^
* CountData.java 2vWkAC;
* `
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* Created on 2007年1月1日, 下午4:44 2"__jp:(
* <V6#)^Or
* To change this template, choose Tools | Options and locate the template under JH)&Ca>S
* the Source Creation and Management node. Right-click the template and choose G)< k5U4
* Open. You can then make changes to the template in the Source Editor. \re.KB#R
*/ RtqW!ZZ:H
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package com.tot.count; }FM<uBKW
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/** ~Dy0HVE
* w-\fCp )
* @author nosEo?{
*/ 3ZZJYf=
public class CountBean { sn Ekei|0
private String countType; U_VD* F4Bv
int countId; ;U7\pc;S
/** Creates a new instance of CountData */ TfZO0GL$
public CountBean() {} Ok:@F/ v
public void setCountType(String countTypes){ DJn>. Gd
this.countType=countTypes; 'HqAm$V+
} >_F&oA#
public void setCountId(int countIds){ yY"%6k,ZB
this.countId=countIds; t?0=;.D
} Nc"h8p?
public String getCountType(){ ZVGw@3
return countType; $%t{O[(
} _K;rM7
public int getCountId(){ O-y"]Wrv
return countId; /(}V!0\?
} uq 6T|Zm
} T.1z<l""
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CountCache.java S[u<vHy
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/* d>AVUf<o~
* CountCache.java 8\a)}k~4
* a"&Z!A:Z=
* Created on 2007年1月1日, 下午5:01 sztnRX_
* Mys;Il"
* To change this template, choose Tools | Options and locate the template under L>L4%?
* the Source Creation and Management node. Right-click the template and choose b _u&%
* Open. You can then make changes to the template in the Source Editor. F2:7UNy,
*/ u8W*_;%:
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package com.tot.count; "RShsJZMH
import java.util.*; tNUcmiY
/** VJ$C)0xQA
* T\WNT#My
* @author #Se
*/ /=3g-$o{`
public class CountCache { Ha/\&Z(
public static LinkedList list=new LinkedList(); q7)$WXe2LM
/** Creates a new instance of CountCache */ _ssHRbE
public CountCache() {} '<}7bw}+c
public static void add(CountBean cb){ !^LvNW\|
if(cb!=null){ .K7A!;
list.add(cb); cX=` Tl
} zm~~mz A
} C>MoR 3]
} vj_oMmjKw
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CountControl.java BF_k~
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/* &U,f~KJ
* CountThread.java oqY?#p/
* Xoik%T-
* Created on 2007年1月1日, 下午4:57 b%_QL3m6
* +(/Z=4;,[
* To change this template, choose Tools | Options and locate the template under 1a)_Lko
* the Source Creation and Management node. Right-click the template and choose ad~ qr n\
* Open. You can then make changes to the template in the Source Editor. GqAedz ;.
*/ F9c2JBOM
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package com.tot.count; sEj:%`l|
import tot.db.DBUtils; 7<tqT
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import java.sql.*; wM yPR_
/** n$Pv2qw
* (
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* @author sXydMk`J
*/ Bdg*XfXXk
public class CountControl{ M84LbgGM%
private static long lastExecuteTime=0;//上次更新时间 a-}%R
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 54;iLL
/** Creates a new instance of CountThread */ |knP
public CountControl() {} RXof$2CZS
public synchronized void executeUpdate(){ '~f@p~P
Connection conn=null; cp2fDn
PreparedStatement ps=null; HdLkof2i
try{ 7]^ }
conn = DBUtils.getConnection(); ef.lM]cO
conn.setAutoCommit(false); )N6R#
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); p/5!a~1'xN
for(int i=0;i<CountCache.list.size();i++){ zbi
CountBean cb=(CountBean)CountCache.list.getFirst(); \=_8G:1
CountCache.list.removeFirst(); 0Fw\iy1o
ps.setInt(1, cb.getCountId()); e7?W VV,
ps.executeUpdate();⑴ >4VU
//ps.addBatch();⑵ !'gz&3B~h
} "''<:K|
//int [] counts = ps.executeBatch();⑶ m0*
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conn.commit(); sogbD9Jc
}catch(Exception e){ 87Uv+((H
e.printStackTrace(); 5ya3mNE
} finally{ IMR|a*=`c
try{ ~^euaOFU 6
if(ps!=null) { X @Bpjg
ps.clearParameters(); R P X`2zr
ps.close(); m ZhVpIUO
ps=null; v\k,,sI
} v-gT
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}catch(SQLException e){} rzmk-V
DBUtils.closeConnection(conn); 'H'+6
} h@~X*yLKh
} e>>G4g
public long getLast(){ ICTtubjV"
return lastExecuteTime; bSR<d
} [s34N+vU
public void run(){ 0B4(t6o
long now = System.currentTimeMillis(); wW<"l"x,
if ((now - lastExecuteTime) > executeSep) { W@C56fCa
//System.out.print("lastExecuteTime:"+lastExecuteTime); *0hiPj:
//System.out.print(" now:"+now+"\n"); )f!dG(\
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); '=~y'nPG7
lastExecuteTime=now; Z+dR(9otH3
executeUpdate(); )eFFtnu5
} PJYA5"}W
else{ OT&E)eR
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); M$W#Q\<*#r
} RsD`9>6)
} t(Zs*c(
} Wi5|9
//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 JAb?u.,Ns_
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类写好了,下面是在JSP中如下调用。 p<zXuocQ
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<% ThlJhTh<%4
CountBean cb=new CountBean(); >a7(A#3@d
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); eE{L>u
CountCache.add(cb); :.Qe=}9
out.print(CountCache.list.size()+"<br>"); sBb.Y
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CountControl c=new CountControl(); UvZ@"El
c.run(); ;a3nH
out.print(CountCache.list.size()+"<br>"); ,4Fqvg
%>