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: #e&j]Q$Eh
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CountBean.java |LKhT4rE
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/* ~=%eOoZP;c
* CountData.java {a_=4a
* mT@UQCG
* Created on 2007年1月1日, 下午4:44 <(d^2-0
* PiI ):B>
* To change this template, choose Tools | Options and locate the template under FqsG#6|x
* the Source Creation and Management node. Right-click the template and choose +n9&q#ah
* Open. You can then make changes to the template in the Source Editor. !`,6E`Y#
*/ -'{ioHt&X/
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package com.tot.count; O<f_-n@G|
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/** sx8mba(
* fJOU1%
* @author '.atbl
*/ WKBPqfC
public class CountBean { 9R>A,x(
private String countType; /j
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int countId; \UJ:PW$7
/** Creates a new instance of CountData */ o&*1Mx<+
public CountBean() {} N&S:=x:$S
public void setCountType(String countTypes){ NNutpA}s
this.countType=countTypes; 3-32q)8
} &4"(bZ:LO
public void setCountId(int countIds){ S~YrXQ{_>-
this.countId=countIds; nP'ab_>b
} (5-"5<-@R
public String getCountType(){ `;*=2M<c
return countType; w[PW-m^`
} }?*:uf
public int getCountId(){ |Y/iq9l
return countId; lhQ*;dMj%"
} /RmLV
} QEUg=*3W=
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CountCache.java L)Un9&4L
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/* ?xK9
* CountCache.java ,n &|+&
* TKoO\\
* Created on 2007年1月1日, 下午5:01 JEY%(UR8
* k>VP<Zm13
* To change this template, choose Tools | Options and locate the template under Ow//#:
* the Source Creation and Management node. Right-click the template and choose ~DqNA%Mb
* Open. You can then make changes to the template in the Source Editor. ,X$S4>
*/ }}t"^m s
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package com.tot.count; x"AYt:ewuc
import java.util.*; a;*&q/{o
/** [p4a\Qg0
* -Rjn<bTIy
* @author P|HY=RMa
*/ L$@RSKYp
public class CountCache { EW2e k^
public static LinkedList list=new LinkedList(); ;1{S"UY
/** Creates a new instance of CountCache */ ?H*_:?=6
public CountCache() {} ,vg8iRa
public static void add(CountBean cb){ #J2856bzS
if(cb!=null){ &e,xN;
list.add(cb); dP)8T
} j nI)n*
} L>@0Nne7
} -iH/~a
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CountControl.java %5F=!(w
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/* I|WBT
* CountThread.java ;C{2*0"H|
* }b\d CGVr
* Created on 2007年1月1日, 下午4:57 x(mY$l,il
* zT_{M
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* To change this template, choose Tools | Options and locate the template under [gv2fqpP
* the Source Creation and Management node. Right-click the template and choose S'3l<sY
* Open. You can then make changes to the template in the Source Editor. uu#ALB
Jm
*/ *"9b?`E
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package com.tot.count; NO* 1km[#
import tot.db.DBUtils; s/,St!A4!
import java.sql.*; h+Dg"j<[
/** ,T&B.'cq
* ;Rwr5
* @author IK%j+UB
*/ bd)A6a\h
public class CountControl{ ~=0zZTG
private static long lastExecuteTime=0;//上次更新时间 (5G^"Srw
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 R
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/** Creates a new instance of CountThread */ 2^qY,dL
public CountControl() {} {Ja#pt
public synchronized void executeUpdate(){ jr!x)yd
Connection conn=null; U8<GD|
PreparedStatement ps=null; xhqIE3gd
try{ =euoSH
D}
conn = DBUtils.getConnection(); YJ!6)d?C.
conn.setAutoCommit(false); X0U{9zP
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); KtV_DjH:
for(int i=0;i<CountCache.list.size();i++){ WfO6Fvx%
CountBean cb=(CountBean)CountCache.list.getFirst(); bR;H@Fdg?
CountCache.list.removeFirst(); C@Wm+E~;8
ps.setInt(1, cb.getCountId()); MR+ndB<
ps.executeUpdate();⑴ =cRJtn
//ps.addBatch();⑵ gCwg ;c-
} pQEHWq"Q
//int [] counts = ps.executeBatch();⑶ /"/$1F%{
conn.commit(); @~a52'\
}catch(Exception e){ %A W
e.printStackTrace(); Q) FL|
} finally{ q)!{oi{x(
try{ ]Fjz+CGg
if(ps!=null) { YTYYb#"Q
ps.clearParameters(); ~yO.R)4v
ps.close(); l"ih+%S
ps=null; OwDjUKeN
} YHeB<v
}catch(SQLException e){} |dXS+R1
DBUtils.closeConnection(conn); 0HG*KW
} *(r85lEou)
} Lw!@[;2
public long getLast(){ ikm4Y`c
return lastExecuteTime; <cWo]T`X!
} lYy0
public void run(){ Grw_SVa^
long now = System.currentTimeMillis(); f Z \Ev%F
if ((now - lastExecuteTime) > executeSep) { 9$d (`-&9p
//System.out.print("lastExecuteTime:"+lastExecuteTime); AY *
//System.out.print(" now:"+now+"\n"); QR^pu.k@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Bpqq-_@
lastExecuteTime=now; gw5CU)r4$
executeUpdate(); TYLf..i<
} J/
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else{ Mb/R+:C`
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); JXvHsCd?
} ^&Qaf:M
} i&?~QQP`
} k"L_0HK
//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 X|.X4fs
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类写好了,下面是在JSP中如下调用。 D{G#|&;
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<% r4_ c~\jH
CountBean cb=new CountBean(); 5a_K|(~3I
cb.setCountId(Integer.parseInt(request.getParameter("cid")));
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CountCache.add(cb); l?#([(WM
out.print(CountCache.list.size()+"<br>"); i2swots
CountControl c=new CountControl(); .>H7i`1D`
c.run(); 6:h!gY
out.print(CountCache.list.size()+"<br>"); Ou,B3kuQ+
%>