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: yNDplm|9*
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CountBean.java J]4pPDm
<%ba
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/* Z#znA4;)
* CountData.java T6^H%;G
* "fN=Y$G
* Created on 2007年1月1日, 下午4:44 qS?uMms7w
* `E:&a]ul
* To change this template, choose Tools | Options and locate the template under /kH
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* the Source Creation and Management node. Right-click the template and choose e?yrx6
* Open. You can then make changes to the template in the Source Editor. LE]mguvs
*/ Sece#K2J|
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package com.tot.count; ?Jy/]j5fI
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/** W\1V`\gF
* 2uT"LW/(H
* @author {\p&?
*/ oUNuM%g9Dy
public class CountBean { <;P40jDL
private String countType; PHU$<>
int countId; 0qp Pz|h
/** Creates a new instance of CountData */ ^+k~{F,)
public CountBean() {} e754g(|>b
public void setCountType(String countTypes){ O]VHX![Y$
this.countType=countTypes;
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} peD7X:K\s
public void setCountId(int countIds){ ^SvGSxi
this.countId=countIds; }O+`X) 9
} oa<%R8T?@
public String getCountType(){ M"!{Dx~
return countType; o~`KOe
} \ Dccf_(Pb
public int getCountId(){ aNDpCpy
return countId; 5KgAY;|
} ,vs# (d6 G
} mbZn[D_zi
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CountCache.java Qy7 pM8~h
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/* b-?d(-
* CountCache.java ~jD~_JGp
* GWW#\0*Bn
* Created on 2007年1月1日, 下午5:01 -jWXE
* )z!#8s
* To change this template, choose Tools | Options and locate the template under Wf{&D>
* the Source Creation and Management node. Right-click the template and choose /C6$B)w_*{
* Open. You can then make changes to the template in the Source Editor. 34:Y_*
*/ !t!'
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package com.tot.count; #7Jvk_r9Y
import java.util.*; DDBf89$\
/** %G/(7l[W
* pF<KhE*V
* @author `dJ?j[P,p
*/ S5/p3;O\c
public class CountCache { qlm7eS"sy
public static LinkedList list=new LinkedList(); o7kQ&w
/** Creates a new instance of CountCache */ #ja6nt8GC
public CountCache() {} J*D3=5&
public static void add(CountBean cb){ s)~Wcp'+M:
if(cb!=null){ $J9/AFzO"
list.add(cb); 4Hq6nT/
} bPA1>p7
} mt\pndTy7!
} fRK=y+gl@
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CountControl.java :V~
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/* jZR2Nx}16
* CountThread.java k2:mIp\
* OLE@35"v]
* Created on 2007年1月1日, 下午4:57 iLk"lcX
* r1a/'+
* To change this template, choose Tools | Options and locate the template under S
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* the Source Creation and Management node. Right-click the template and choose vl>_;}W7
* Open. You can then make changes to the template in the Source Editor. Y/]J0D
*/ 1
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package com.tot.count; |\T!,~
import tot.db.DBUtils; v(`5exWV
import java.sql.*; of/'
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/** >uR;^ B5m
* eCwR
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* @author p+}eP|N
*/ d6ckvD[
public class CountControl{ =VGRM#+D
private static long lastExecuteTime=0;//上次更新时间 C )BVsHT4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ^ 2LqKo\T
/** Creates a new instance of CountThread */ nVoP:FHH
public CountControl() {} xG:7AGZ$[
public synchronized void executeUpdate(){ oH1]-Nl$
Connection conn=null; n0b{Jg *
PreparedStatement ps=null; M9Qx F
try{ 3\j3vcuy
conn = DBUtils.getConnection(); '@f#GNRT
conn.setAutoCommit(false); 17[vq!x6
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); :Fdk`aC
for(int i=0;i<CountCache.list.size();i++){ d(F4-kBd
CountBean cb=(CountBean)CountCache.list.getFirst(); tUhr gc
CountCache.list.removeFirst(); G5*_
ps.setInt(1, cb.getCountId()); xM13OoU
ps.executeUpdate();⑴ sfR0wEqI
//ps.addBatch();⑵ Fiaeo0
} rq|>z .
//int [] counts = ps.executeBatch();⑶ V PI_pK
conn.commit(); 9d8U@=
}catch(Exception e){
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e.printStackTrace(); N >k,"=N/
} finally{ MrhJk
try{ Hh'o:j(^
if(ps!=null) { vPM2cc/o
ps.clearParameters(); 9&Ny;oy#6
ps.close(); AME<V-5
ps=null; T;#:Y
} LX7<+`aa
}catch(SQLException e){} ZG)6{WS
DBUtils.closeConnection(conn); ~QU\kZ7Z
} LsaRw-4.c
} }0 =gP?.kE
public long getLast(){ gsVm)mkd
return lastExecuteTime; [-h=L
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} [-2Tj)P
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public void run(){ $o^N_`l
long now = System.currentTimeMillis(); v2 }>/b)
if ((now - lastExecuteTime) > executeSep) { <zp|i#~
//System.out.print("lastExecuteTime:"+lastExecuteTime); H;Gd
//System.out.print(" now:"+now+"\n"); bix}#M
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); SOeRQb'
lastExecuteTime=now; ZqfoO!Ta
executeUpdate(); (5>IF,}!L
} J-W8wCq`
else{ Vm%0436wOY
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); a]=j
} 85#+_}#
} ?}<Wmy2A
} &NK6U
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 j,v2(e5:
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类写好了,下面是在JSP中如下调用。 U}SN#[*
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<% J"
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CountBean cb=new CountBean(); o_?A^u
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >qci$
CountCache.add(cb); uY:u[
out.print(CountCache.list.size()+"<br>"); J#Agk^Y 5
CountControl c=new CountControl(); wu19Pg?F
c.run(); nACKSsWqI
out.print(CountCache.list.size()+"<br>"); :.?%e{7
%>