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\ tBmL_s
s2nZW pIy
CountBean.java BpF}H^V-
m^^#3*qa
/* ![Vrbe P
* CountData.java 2J`LZS
* 2[KHmdgtB
* Created on 2007年1月1日, 下午4:44 UZgrSX {
* \ow(4O#
* To change this template, choose Tools | Options and locate the template under q?f-h<yRQ
* the Source Creation and Management node. Right-click the template and choose -BsZw.
7P
* Open. You can then make changes to the template in the Source Editor. Mv7tK
l
*/ ~"h V-3U
O:dUzZR['
package com.tot.count; .;D'
^brh\M,:@
/** oK&G
* pFwe&_u]
* @author AUl[h&s
*/ Q2!RFtXV
public class CountBean { c>C!vAg
private String countType;
O@rZ^Aa
int countId; vLCm,Bb2L
/** Creates a new instance of CountData */ dBW4%Zh
public CountBean() {} 4_4|2L3
public void setCountType(String countTypes){ G2J4N2hu
this.countType=countTypes; FWS!b!#,N
} Ej`G(
public void setCountId(int countIds){ RLDu5
this.countId=countIds; t1aKq)?
} Fk?KR
public String getCountType(){ HA0yX?f]
return countType; h:vI:V[/X
} hllb\Y)XL
public int getCountId(){ D,s[{RW+q
return countId; B{1yMJA
} "VAbUs
} UD5f+,_;
/{Z<!7u;U
CountCache.java }oii|=,#^
y $L&N0z
/* /j(<rz"j
* CountCache.java w1= f\
* xf{=~j/L
* Created on 2007年1月1日, 下午5:01 4{"
v
* C7Hgzc|U
* To change this template, choose Tools | Options and locate the template under XJ3aaMh"
* the Source Creation and Management node. Right-click the template and choose hrbeTtqi
* Open. You can then make changes to the template in the Source Editor. yGb^k R}d
*/ )KY U[
6 x8lnXtA
package com.tot.count; qp]sVY
import java.util.*; 4WQ
96|F
/** Uz7V2r%]
* #YLI"/Kn
* @author x}N1Wl=8g
*/ d,t'e?
public class CountCache { S,C/l1s
public static LinkedList list=new LinkedList(); OEHw%
/** Creates a new instance of CountCache */ kgRgHkAH~
public CountCache() {} cHwN=mg]S
public static void add(CountBean cb){ cLMFC1=b
if(cb!=null){ W1UqvaR
list.add(cb); N3Z6o.k
} (m=F
} w{Y:p[}
} 5OC3:%g
SJ:Wr{ Or3
CountControl.java 0U:9&jP,
&>hln<a>
/* 0ac'<;9]zP
* CountThread.java X!]p8Q y
* ybgw#jv=
* Created on 2007年1月1日, 下午4:57 m pM,&7}
*
NW?h~2
* To change this template, choose Tools | Options and locate the template under Oxh.&
* the Source Creation and Management node. Right-click the template and choose 97VS
xhr
* Open. You can then make changes to the template in the Source Editor. 6x!
q
*/ T-lHlm
>zv}59M
package com.tot.count; UC"_#!3
import tot.db.DBUtils; [b@9V_
import java.sql.*; F#7A6|
/** IQ9Rvnna
* ~ponYc.Y
* @author .BZ3>]F3<
*/ Uj~
:|?Wz
public class CountControl{ 1?T^jcny:M
private static long lastExecuteTime=0;//上次更新时间 6XGqZ!2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 h)yAge
/** Creates a new instance of CountThread */ j}$Q`7-wB1
public CountControl() {} }Ym~[S*x
public synchronized void executeUpdate(){ BoPJ;6?>}
Connection conn=null; B,ZLX/c9
PreparedStatement ps=null; #^<Rx{
try{ 5> =Ia@I
conn = DBUtils.getConnection(); ZDl(q~4?z
conn.setAutoCommit(false); @jH8x!5u:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); v
iM6q<Ht
for(int i=0;i<CountCache.list.size();i++){ Z_?r5M;
CountBean cb=(CountBean)CountCache.list.getFirst(); GvD{ I;
CountCache.list.removeFirst(); 1;y?!;FD
ps.setInt(1, cb.getCountId()); OW8"7*irT
ps.executeUpdate();⑴ A(qy>x-BI
//ps.addBatch();⑵ e/ V8lo
} GAcU8MD
//int [] counts = ps.executeBatch();⑶ {@`Z`h"N
conn.commit(); *'ex>4^
}catch(Exception e){ 5TcirVO82
e.printStackTrace(); ik|iAWy
} finally{ 'B$qq[l]S
try{ E.OL_ \
if(ps!=null) { q|ww fPez7
ps.clearParameters(); R9V v*F]m@
ps.close(); npdpKd+*K"
ps=null; t0gLz
J
} _l!TcH+e
}catch(SQLException e){} +;wu_CQu
DBUtils.closeConnection(conn); <Q?X'.
} <YBA
7i
} HESORa;
public long getLast(){ >2?O-WXe
return lastExecuteTime; 0=Z_5.T>
} D<*#. >
public void run(){ vOYG&)Jm
long now = System.currentTimeMillis(); xk8P4`;d$
if ((now - lastExecuteTime) > executeSep) { 2x&mJ}o#k
//System.out.print("lastExecuteTime:"+lastExecuteTime); vFGFFA/K}N
//System.out.print(" now:"+now+"\n"); kkE1CHY
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 7tr;adjs
lastExecuteTime=now; c_^-`7g
executeUpdate(); 9hIcnPu
} O(oGRK<xM
else{ ~Fd<d[b?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); eZ~ZWb, %
} rZv5>aEI
} cA{zyq26
} 'X(G><R9
//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 Gdf*x<T1
.I&]G
类写好了,下面是在JSP中如下调用。 _4jRUsvjY
|0$wRl+kN
<% }^
j"@{~
CountBean cb=new CountBean(); rwUKg[
1N
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 2,O;<9au<
CountCache.add(cb); Lg[_9`\
out.print(CountCache.list.size()+"<br>"); h tn?iLq
CountControl c=new CountControl(); Dk XB
c.run(); RwC1C(ZP
out.print(CountCache.list.size()+"<br>"); #(G#O1+
%>