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: A ws#>l<
[=U7V;5($
CountBean.java ]Vb#(2<2
=V5.c+
/* .yTk/x?
* CountData.java sF+0v p
* Nr`nL_DQ
* Created on 2007年1月1日, 下午4:44 lR.a3.~
* {+xUAmd
* To change this template, choose Tools | Options and locate the template under u~s'<c+8_
* the Source Creation and Management node. Right-click the template and choose dt`L}Yi
* Open. You can then make changes to the template in the Source Editor. =AD/5E,3
*/ %4 SREq
3]N}k|lb%
package com.tot.count; M8[YW|VkP
tB_ V%qH
/** hsqUiB tc6
* W$'pUhq\H
* @author C9=f=sGL
*/ J $e.$ah;
public class CountBean { K,IOD
t
private String countType; N7oMtlvL[w
int countId; J~_p2TZJ\3
/** Creates a new instance of CountData */ J.<eX=<
public CountBean() {} l*v([@A\
public void setCountType(String countTypes){ =rBFMTllM
this.countType=countTypes; 7Ck;LF}>0
} }2NH>qvY
public void setCountId(int countIds){ =fsaJ@q,R
this.countId=countIds; 5)nv
} )D[ypuM&
public String getCountType(){ izC>-
return countType; LpmspIPvf
} 9d{W/t?NH
public int getCountId(){ mSj[t
return countId; mr('zpkRq
} pRU6jV 6e)
} nZ bg
h[Iu_#HMa
CountCache.java :.35pp,0
("lcL2Bq
/* Vbj?:29A
* CountCache.java y:42H tS
* '^/E2+
* Created on 2007年1月1日, 下午5:01 xJ"Zg]d{
* /ruf1?\,R
* To change this template, choose Tools | Options and locate the template under 6~!YEuA
* the Source Creation and Management node. Right-click the template and choose i;xg[e8.
* Open. You can then make changes to the template in the Source Editor. Nl_;l
*/
9Np0<e3p
|wLQ)y*
package com.tot.count; ##s!-.T
import java.util.*; i3%~Gc63
/** W^Rb~b^?
* J.nVEqLZ
* @author H]-W$V
*/ ?s?uoZ /2
public class CountCache { NDg]s2T
public static LinkedList list=new LinkedList(); J<BdIKCma
/** Creates a new instance of CountCache */ GDcV1$NA
public CountCache() {} )/U1; O
public static void add(CountBean cb){ ^LNc
if(cb!=null){ 2ga}d5lu
list.add(cb); RyhR#
} ; Q 6:#
} N|~&Q!A&
} 0sUc6_>e
0iL8i#y*
CountControl.java FRg6-G/S
`UI)H*GA8
/* >WDpBn:
* CountThread.java gK<- *v
* ('lnQD.Hd
* Created on 2007年1月1日, 下午4:57 Za f)
* <+b:
* To change this template, choose Tools | Options and locate the template under V8sY7QK=
* the Source Creation and Management node. Right-click the template and choose q@sH@-z4]
* Open. You can then make changes to the template in the Source Editor. E^YbyJ=1
*/ ;VuB8cnL`
,9pi9\S
package com.tot.count; v8@dvT<
import tot.db.DBUtils; ?oJ~3Kg
import java.sql.*; \\lC"Z#J`
/** R:xmcUq}
(
* P
X0#X=$
* @author }dHiW:J>
*/ amSyGQ2
public class CountControl{ O.E0LCABC
private static long lastExecuteTime=0;//上次更新时间 :I$2[K
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 >'jM8=o*Ax
/** Creates a new instance of CountThread */ CS{9|FNz
public CountControl() {} h|H;ZC(B
public synchronized void executeUpdate(){ GMNb;D(>K
Connection conn=null; E\zhxiI
PreparedStatement ps=null; b910Z?B^L
try{ bpx=&74,6m
conn = DBUtils.getConnection(); H<xC%/8
conn.setAutoCommit(false); -,;Ep'
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); <^\r9Qxl
for(int i=0;i<CountCache.list.size();i++){ D1n2Z:9
CountBean cb=(CountBean)CountCache.list.getFirst(); 2|=_kN8;
CountCache.list.removeFirst(); $G_<YVXcG
ps.setInt(1, cb.getCountId()); :acQK=fe
ps.executeUpdate();⑴ d0=nAZZ
//ps.addBatch();⑵ uUe\[-~
} 5ZcnZlOOQ
//int [] counts = ps.executeBatch();⑶ 3k<#;(
conn.commit(); (lnQ!4LK
}catch(Exception e){ UBVb#FNF
e.printStackTrace(); kYs|")isj
} finally{ x-pMT3m\D#
try{ |gVO Iq
if(ps!=null) { ?>y-5B[K/(
ps.clearParameters(); K7.<,E"M.
ps.close(); 3DHm9n+/:
ps=null;
xAjQW=
} 7&3URglsL"
}catch(SQLException e){} "(NHA+s/
DBUtils.closeConnection(conn); W.|6$hRl)
} `Ek !;u>
} r$F]e]Ic\
public long getLast(){ p.9v<I%0
return lastExecuteTime; ptR
} ;Kf|a}m -
public void run(){ %RN-J*s]
long now = System.currentTimeMillis(); c-.>C)
if ((now - lastExecuteTime) > executeSep) { #H[4?4r
//System.out.print("lastExecuteTime:"+lastExecuteTime); _PM<25Y,@
//System.out.print(" now:"+now+"\n"); [&CM-`
N
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); a~*V
lastExecuteTime=now; ^kr)U8
executeUpdate(); W/>?1+r.Z
} iy]}1((hR
else{ [hL1PWKs
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); !I[n|r "
} tD]&et
} 32iI :u
} 2eU[*x
//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 f}X8|GlBo
m-8 9nOls
类写好了,下面是在JSP中如下调用。 .A\ \v6@
xp&!Cl>C3\
<% @?m8/t9.
CountBean cb=new CountBean(); mr!I}I7x&x
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); DQ\&5ytP
CountCache.add(cb); Hg`{9v
out.print(CountCache.list.size()+"<br>"); mM}Ukmy
CountControl c=new CountControl(); !XG&=Rd?
c.run(); @vYmkF`
out.print(CountCache.list.size()+"<br>"); 'pY;]^M
%>