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: "'}v 0*[
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CountBean.java #1jtprc
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/* Bsu=^z
* CountData.java V:(w\'wm
* 1Oca@E\Z.
* Created on 2007年1月1日, 下午4:44 D#/%*|
* f.$aFOn
* To change this template, choose Tools | Options and locate the template under c6Yf"~TD0
* the Source Creation and Management node. Right-click the template and choose 43u PH1
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* Open. You can then make changes to the template in the Source Editor. PQ&Q71
*/ \o62OfF!
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package com.tot.count; 2iR:*}5
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/** A^4kYOe
* Q/3tg
* @author {+/
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*/ PV]k3&y
public class CountBean { ||'i\X|[
private String countType; ){:q;E]^fB
int countId; \C+*loLs
/** Creates a new instance of CountData */ ^z *):e
public CountBean() {} ~E<PtDab
public void setCountType(String countTypes){ (?!(0Ywbg
this.countType=countTypes; ebO`A2V'(
} yBPt%EF
public void setCountId(int countIds){ ]{Mci]H6T
this.countId=countIds; cXOje"5i
} k%Ma4_Z
public String getCountType(){ q:2aPfo&
return countType; TXd5v#_vo
} v9t47>V
public int getCountId(){ y~==waZw
return countId; >/!7i3Ow-
} ;o-\. =l
} {z5V{M(|w3
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CountCache.java P0'e"\$
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/* ,Lt~u_ lve
* CountCache.java IFd )OZ5
* K9e~Wl<3
* Created on 2007年1月1日, 下午5:01 [)Z'N/;0
* Qq,i
* To change this template, choose Tools | Options and locate the template under OYszW]UMg
* the Source Creation and Management node. Right-click the template and choose W"b&M%y|
* Open. You can then make changes to the template in the Source Editor. p@?7^nIR*u
*/ b(PHZCy#
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package com.tot.count; toS(UM n
import java.util.*; 0On?{Bw
/** Cec9#C
* zdxT35h
* @author 8
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*/ M>*0r<qn
public class CountCache { B`?N,N"
public static LinkedList list=new LinkedList(); 5y1or
/** Creates a new instance of CountCache */ 4zo4H~@gk
public CountCache() {} JCcN>DtP
public static void add(CountBean cb){ F[>7z3I
if(cb!=null){ Od0S2hHO
list.add(cb); ;;EDN45
} N3uMkH-<
} BA~a?"HS
} /6+1{p
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CountControl.java 0Y2\n-`z
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/* JP{UgcaF
* CountThread.java 9
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* cZNi~
* Created on 2007年1月1日, 下午4:57 0lX)Cl
* pyUNRqp
* To change this template, choose Tools | Options and locate the template under I#"t'=9H
* the Source Creation and Management node. Right-click the template and choose j2RRSz&9
* Open. You can then make changes to the template in the Source Editor. >Y7r\
*/ j y7
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package com.tot.count; cU7rq j_
import tot.db.DBUtils; Hze-Ob8
import java.sql.*; Z} c'Bm(
/** 2{Wo-B,wt~
* `d75@0:
* @author 285_|!.Y
*/ k/df(cs
public class CountControl{ 4rI:1yGt@
private static long lastExecuteTime=0;//上次更新时间 g d z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;*y|8od
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/** Creates a new instance of CountThread */ X Y~;)<s_
public CountControl() {} S3SV.C:z>
public synchronized void executeUpdate(){ _Ny8j~
Connection conn=null; ;(K
PreparedStatement ps=null; 1s Br.+p
try{ Hl4\M]]/&
conn = DBUtils.getConnection(); dSwm|kIa
conn.setAutoCommit(false); ,VAp>x+O
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); GtF2@\
for(int i=0;i<CountCache.list.size();i++){ kt:)W])V
CountBean cb=(CountBean)CountCache.list.getFirst();
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CountCache.list.removeFirst(); b& V`<'{
ps.setInt(1, cb.getCountId()); 3AK(dC[ri
ps.executeUpdate();⑴ 6G'<[gL
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//ps.addBatch();⑵ 9u?(^(.
} 4_tR9 w"
//int [] counts = ps.executeBatch();⑶ Kaf>
conn.commit(); x Y| yI>
}catch(Exception e){ <D;MT96SG
e.printStackTrace(); [!G)$<
} finally{ x"vwWJNQ
try{ cFLd)mt/
if(ps!=null) { !L77y^oV
ps.clearParameters(); -PM)EGSk{
ps.close(); ~uB'3`x
ps=null; l<TIG3bs
} -n$ewV
}catch(SQLException e){} tVunh3-
DBUtils.closeConnection(conn); i`+B4I8[
} 1 o|T
} Sr&T[ex,.
public long getLast(){ vVAb'`ysv
return lastExecuteTime; }'lNi^"XL
} Uan,H1a
public void run(){ vXb:
long now = System.currentTimeMillis(); @44P4?;
if ((now - lastExecuteTime) > executeSep) { ymtd>P"
//System.out.print("lastExecuteTime:"+lastExecuteTime); \83sSw
//System.out.print(" now:"+now+"\n"); eaQ90B4
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >Dne? 8r
lastExecuteTime=now; 2/@D7>F&g
executeUpdate(); FSU<Y1|XM
} 0qv$:w)g+v
else{ 8Y#bN*!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0N{+y}/G
} ,d|vP)SS
} hq?jdNy
:
} YdI0E
//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 &3Tx@XhO
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类写好了,下面是在JSP中如下调用。 _UkmYZ/
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<% Jf)3< ~G
CountBean cb=new CountBean(); cOkgoL" 4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); , H2YpZk
CountCache.add(cb); ~GG?GB
out.print(CountCache.list.size()+"<br>"); <qhBc:kc
CountControl c=new CountControl(); s*Ih_Ag=:
c.run(); S5_t1wqBJ
out.print(CountCache.list.size()+"<br>"); u g\w\b
%>