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: G{ F>=z"(l
m0/J3
CountBean.java EYG&~a>L*
y$\K@B4
/* 7B+?1E(
* CountData.java iHQFieZ.E
* I%{U~
* Created on 2007年1月1日, 下午4:44 ChGwG.-%L
* _v]I6<!5U
* To change this template, choose Tools | Options and locate the template under Gs*ea'T)
* the Source Creation and Management node. Right-click the template and choose }L:LcM
* Open. You can then make changes to the template in the Source Editor. 1&wZJP=
*/ t41\nTZr
z36ny o
package com.tot.count; GpxGDN3?
L{
.r8wSrI
/** 9YB~1M
* \^':(Gu4o
* @author lWnV{/q\X
*/ TSE(Kt
public class CountBean { C8NbxP
private String countType; yHT}rRS8
int countId; tk_y~-xz
/** Creates a new instance of CountData */ o&I0*~sN
public CountBean() {} RTF{<,E.UX
public void setCountType(String countTypes){ /j3oHi$
this.countType=countTypes; vR+(7^Yy
} MQR2UK(
public void setCountId(int countIds){ VAq(
t
this.countId=countIds; F
\} Kh3
} z XVQLz5
public String getCountType(){ a$;+-Y
return countType; ;x+4jpH]B
} TpMfk7-
public int getCountId(){ !.3
MtXr
return countId; '90B),c{
} ub.pJJlC
} yu}4L'e
,{zvGZ|
CountCache.java `EWeJ(4Z@
)Tb{O
/* b/ZX}<s(1=
* CountCache.java :(I)+;M}P
* @JN%P}4)
* Created on 2007年1月1日, 下午5:01 _k6N(c2Nd
* 4Ag+
* To change this template, choose Tools | Options and locate the template under U.>n]/&
* the Source Creation and Management node. Right-click the template and choose Gg,,qJO
* Open. You can then make changes to the template in the Source Editor. t}*teo[
*/ ojyG|Y
E7*1QR{Q
package com.tot.count; ~49+$.2
import java.util.*; Z< uwqA
/** Rs<,kMRGVL
* EcwHO
* @author ?A2EuvQH]
*/ =X% D;2
public class CountCache { ;Oe6SNquT
public static LinkedList list=new LinkedList(); ^Ko0zz|R/
/** Creates a new instance of CountCache */ %}$6#5"';
public CountCache() {} .fQDj{
public static void add(CountBean cb){ TzX>d<x
if(cb!=null){ Vvv
-f
list.add(cb); [vV-0Lx"
} Ep0Aogp29
} Z\dILt:#z
} lzm9ClkfH
Or6'5e?N
CountControl.java 9';0vrFeM
3OM\R%M
/* *?\2Ohp
* CountThread.java _#N~$
* n,xK7icYNQ
* Created on 2007年1月1日, 下午4:57 1l1X1
* vLpE|QZ s
* To change this template, choose Tools | Options and locate the template under LU;ma((yy[
* the Source Creation and Management node. Right-click the template and choose D(Xv shQ
* Open. You can then make changes to the template in the Source Editor. ;{HxY98Q
*/ mP:mzmUw
5HOhk"
package com.tot.count; QuF%m^aE
import tot.db.DBUtils; Of:e6N
import java.sql.*; #2u-L~n
/** =YPWt>\a}
* Y z%=
* @author CR,
Y%0vQ
*/ a?+) K
public class CountControl{ RsrZ1dhPvV
private static long lastExecuteTime=0;//上次更新时间 >1joCG~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3zh'5qQ
/** Creates a new instance of CountThread */ ^Jc~G~x4*
public CountControl() {} uP+
j_is
public synchronized void executeUpdate(){ `o:)PTQNg
Connection conn=null;
uiiA)j*!
PreparedStatement ps=null; u6 B (f;
try{ Zc%S`zK`7
conn = DBUtils.getConnection(); urtcSq&H'
conn.setAutoCommit(false); PT\5P&2o@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >8>.o[Q&
for(int i=0;i<CountCache.list.size();i++){ )FU4i N)ei
CountBean cb=(CountBean)CountCache.list.getFirst(); R@"N{ [9
CountCache.list.removeFirst(); 7&HP2r
ps.setInt(1, cb.getCountId()); HjV^6oP
ps.executeUpdate();⑴ 1f}S:Z
//ps.addBatch();⑵ 6E_YQbdy
} iB]kn(2C
//int [] counts = ps.executeBatch();⑶ ODEy2).
conn.commit(); *wh'4i}u
}catch(Exception e){ y& Dd
e.printStackTrace(); {P = {)
} finally{ ybYSz@7
try{ ]FFU,me2
if(ps!=null) { /Ee0S8!Z!1
ps.clearParameters(); .h7b 4J
ps.close(); sav2 .w
ps=null; CTPn'P=\C
} 1noFXzeU3
}catch(SQLException e){} fcV/co_S6
DBUtils.closeConnection(conn); *w@>zkBl
} E]ZM`bex&
} 6^ /C+zuX
public long getLast(){ Ylo@
return lastExecuteTime; kMI\GQW
} Ex@#!fz{%
public void run(){ Sb,{+Wk
long now = System.currentTimeMillis(); ]8H;LgM2
if ((now - lastExecuteTime) > executeSep) { -lAA,}&+!
//System.out.print("lastExecuteTime:"+lastExecuteTime); rylllJz|L:
//System.out.print(" now:"+now+"\n"); Gg-<3z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `
0\hm`
lastExecuteTime=now; xRaYm
executeUpdate(); v`v+M4upC
} ?]P&3UU>0z
else{ {/ty{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 71)HxC[6vA
} 2;kab^iv'
} ,,{Uz)>'W6
} k+s<;{
//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 (tVY
/(~#
IE,g
类写好了,下面是在JSP中如下调用。 [n< U>up
TmQ2;3%
<% Wt4!XV
CountBean cb=new CountBean(); uIWCVR8`Y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 1)
@Wcc.
CountCache.add(cb); :X;8$.z
out.print(CountCache.list.size()+"<br>"); 4vy!'r@
CountControl c=new CountControl(); Hq%`DWus\
c.run(); &"L3U
out.print(CountCache.list.size()+"<br>"); y"){?
%>