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: &n:{x}Uc
Or8kp/d
CountBean.java E$A3|rjnoN
~Wei|,w'<
/* /`3#4=5-
* CountData.java FQk!d$BG
* iG#}`
* Created on 2007年1月1日, 下午4:44 kJT+
* :Wc_Utt
* To change this template, choose Tools | Options and locate the template under Qs%B'9")
* the Source Creation and Management node. Right-click the template and choose B2Z_]q$n*
* Open. You can then make changes to the template in the Source Editor. rOcg+5
*/ MLr-,
"gs
,$N#Us(Wa
package com.tot.count; nls
-_em%o3XC
/** z=g$Exl
* pvF-Y9Xb
* @author W3GNA""O
*/ VL\t>n
public class CountBean { B$XwTJ>
private String countType; Ji?#.r`"n
int countId; ~e-z,:Af
/** Creates a new instance of CountData */ UG](go't
public CountBean() {} 6KRO{QK
public void setCountType(String countTypes){ [%pRfjM
this.countType=countTypes; g<wRN#B
} 0^3+P%(o@
public void setCountId(int countIds){ \~~ }N4
this.countId=countIds; ,eRQu.
} nL-K)G,
public String getCountType(){ T^:fn-S}=
return countType; 4CrLkr
} O"Q7Rx
public int getCountId(){ sOpep
return countId; l63hLz
} BUsV|e\
} _las;S'oa
H43MoC
CountCache.java Zsx3/}
,R2U`EO;
/* =a}b+(R
* CountCache.java G8J*Wnwu[K
* [0y$! f4
* Created on 2007年1月1日, 下午5:01 {<=#*qx[Y!
* />44]A<
* To change this template, choose Tools | Options and locate the template under @7<uMasfp
* the Source Creation and Management node. Right-click the template and choose (Un_!)
* Open. You can then make changes to the template in the Source Editor. ,r8Tbk]m
*/ F(,UA+$A
Iz@)!3h
package com.tot.count; Fmr}o(q1
import java.util.*; yN6>VD{F
/** e<cM[6H'D
* !.TLW
* @author +>\id~c(
*/ MTOy8 Im
public class CountCache { eE@&ze>X
public static LinkedList list=new LinkedList(); [eUftr9&0
/** Creates a new instance of CountCache */ fo0+dzazY
public CountCache() {} B9,^mE#
public static void add(CountBean cb){ \tN-(=T
if(cb!=null){ j)C:$
list.add(cb); XYrJ/!*.
} SF*n1V3hx
} 3W_PE+:Kr
} D5,P)[
j+-P :xvP
CountControl.java >znRyQ~bM
-E4XIn
/* ?OlV"zK
* CountThread.java 7 msAhz
* alq%H}FF
* Created on 2007年1月1日, 下午4:57 vVl; |
* tmUFT
* To change this template, choose Tools | Options and locate the template under kwpK1R4zs
* the Source Creation and Management node. Right-click the template and choose BV#78,8(
* Open. You can then make changes to the template in the Source Editor. hC <O`|lF
*/ v<Kmq-b
U}k9 Py
package com.tot.count; =#gEB#$x:
import tot.db.DBUtils; wU\s;
dK
import java.sql.*; NMOut@
/** QPtGdd
* ',^+bgs5
* @author Uyx!E4pl(
*/ ~@.%m"<.
public class CountControl{ L|@y&di
private static long lastExecuteTime=0;//上次更新时间 qqrq11W
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 svf|\p>]H
/** Creates a new instance of CountThread */ !V2/A1?
public CountControl() {} sZGj"_-Hzu
public synchronized void executeUpdate(){ B=8Iu5m
Connection conn=null; GVHV =E
PreparedStatement ps=null; ^z6_ Uw[
try{ >K9#3
4hP
conn = DBUtils.getConnection(); 4;`oUt'.
conn.setAutoCommit(false); _j?e~w&0b
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); _WX tB#
for(int i=0;i<CountCache.list.size();i++){ a]
=
CountBean cb=(CountBean)CountCache.list.getFirst(); jO*l3:!~ \
CountCache.list.removeFirst(); UhA"nt0
ps.setInt(1, cb.getCountId()); @c9^q>Uv
ps.executeUpdate();⑴ :0& X^]\
//ps.addBatch();⑵ k@ZLg9
} 2_vbT!_
//int [] counts = ps.executeBatch();⑶ B33$pUk
conn.commit(); h\v'9
}catch(Exception e){ ,to+oSZE
e.printStackTrace(); ,1OyN]f3
} finally{ c:Wze*vI;
try{ GaX[C<Wt
if(ps!=null) { g<{xC_J
ps.clearParameters(); HK|ynBAo
ps.close(); $`R6=\|
ps=null; Um#Wu]i
} NT@;N /I
}catch(SQLException e){} xk&Jl#v
DBUtils.closeConnection(conn); JRo?s~Ih
} B#/Q'V
} b4^`DHRu6
public long getLast(){ ;q N+^;,2
return lastExecuteTime; E|'h]NY
} M@0;B30L
public void run(){ @2'Mt}R>
long now = System.currentTimeMillis(); 2{|h8oz
if ((now - lastExecuteTime) > executeSep) { 7i&:DePM'q
//System.out.print("lastExecuteTime:"+lastExecuteTime); T^J >ZDA
//System.out.print(" now:"+now+"\n"); 0d8%T<=J
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "HE^v_p
lastExecuteTime=now; \+aC"#+0
executeUpdate(); 5onm]V]
} V3 ~~
else{ P ;IrBq6|o
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); #9K-7je;j
} ")=X4]D
} P#=`2a#G
} 8 r_>t2$
//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 lz1wO5%h
"*G.EiLq
类写好了,下面是在JSP中如下调用。 mZd ,
9
Kq i4hK
<% AU2i%Q!
CountBean cb=new CountBean(); kbM3
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 5mb]Q)f9-
CountCache.add(cb); */|BpakD<
out.print(CountCache.list.size()+"<br>"); yj^+G
CountControl c=new CountControl(); $56,$K`H
c.run(); {%_L=2n6
out.print(CountCache.list.size()+"<br>"); M)SEn/T-
%>