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: jN[6JY1
- 5Wt9
CountBean.java S^"e5n2
z00:59M4
/* {%k;V ~
* CountData.java $0C/S5b
* r[4F?W
* Created on 2007年1月1日, 下午4:44 9: |K]y
* $YQ&\[pDA
* To change this template, choose Tools | Options and locate the template under O]LuL&=s y
* the Source Creation and Management node. Right-click the template and choose ZV^J5wYE
* Open. You can then make changes to the template in the Source Editor. Fmle|
*/ 78BuD[<X-
vl(v1[pU
package com.tot.count; t-'GRme
|0!97*H5
/**
bQQ/7KM
* >!p K94
* @author &!~n=]*sz
*/ `.-k%2?/
public class CountBean { [hj'Yg 8{
private String countType; OQ*. ho
int countId; s(9rBDoY(8
/** Creates a new instance of CountData */ y#0Z[[I0
public CountBean() {} ~u&O
public void setCountType(String countTypes){ ;xH'%W9z
this.countType=countTypes; c,%>7U(w_
} !!#ale&
public void setCountId(int countIds){ q5?mP6
this.countId=countIds; rBPxGBd4
} _qo1 GM&
public String getCountType(){ nt`l6b
return countType; RSeezP6#
} H 6<@
public int getCountId(){ 5j01Mx
A
return countId; |MrH@v7S
} DL!s)5!M
} LZ]pyoi
hQxe0Pdt
CountCache.java b!P;xLcb
J+|V[E<x
/* -dN;\x
* CountCache.java eh(]'%![/
* _[tBLGXD
* Created on 2007年1月1日, 下午5:01 _ILOA]ga#
* SO<K#HfE$?
* To change this template, choose Tools | Options and locate the template under Lcb59Cs6e
* the Source Creation and Management node. Right-click the template and choose L6#d
* Open. You can then make changes to the template in the Source Editor. UVU*5U~
*/ mpAh'f4$*
e|9Bzli{
package com.tot.count; DNO%J^
import java.util.*; ebVfny$D
/** *Yjs$'_2
* [B<{3*R_
* @author ]F-6KeBc
*/ 9'aR-tFun;
public class CountCache { }}2hI`
public static LinkedList list=new LinkedList(); \$UU/\
/** Creates a new instance of CountCache */ },ZL8l{
public CountCache() {} IT33E%G
public static void add(CountBean cb){ NU*6iLIq|F
if(cb!=null){ ]g!<5w
list.add(cb); V1qHl5"
} -e\kIK
%
} M<7*\1
} lV="IP^7
e]fC!>w(\
CountControl.java 1'B?f# s
4"=pcHNV
/* I2Q?7p
* CountThread.java Q{kuB+s
* Y[,C1,
* Created on 2007年1月1日, 下午4:57 *~X\c Z
* Ms3/P| {"p
* To change this template, choose Tools | Options and locate the template under ]F#kM21 1
* the Source Creation and Management node. Right-click the template and choose IrM3Uh
* Open. You can then make changes to the template in the Source Editor. >s~`K^zS
*/ h {btT
j. cH,Y
package com.tot.count; f& *E;l0
import tot.db.DBUtils; r?7^@
import java.sql.*; O-Y E6u
/** @#">~P|Hp
* XA%?35v~
* @author !4fL|0
*/ M-t9zT
public class CountControl{ D1a2|^zt
private static long lastExecuteTime=0;//上次更新时间 eU*hqy?0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 h2K
/** Creates a new instance of CountThread */ l6O(+*6Us
public CountControl() {} ~C+T|
public synchronized void executeUpdate(){ #2iA-5
Connection conn=null; m0YDO0
PreparedStatement ps=null; ~Q\[b%>J
try{ pTd@i1%Nr
conn = DBUtils.getConnection(); i ib-\j4d
conn.setAutoCommit(false); d4tVK0
~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $>Do&TU
for(int i=0;i<CountCache.list.size();i++){ p!
1zhD
CountBean cb=(CountBean)CountCache.list.getFirst(); 2Hj]QN7"
CountCache.list.removeFirst(); )VrHP9fu
ps.setInt(1, cb.getCountId()); I115Rp0
ps.executeUpdate();⑴ *}=W wG
//ps.addBatch();⑵ y6\#{
} qr1^i1%\
//int [] counts = ps.executeBatch();⑶ BZsxf'eN'
conn.commit(); e9nuQ\=
}catch(Exception e){ $:/1U$
e.printStackTrace(); S7]cF5N
} finally{ 0jMrL\>C
try{ Ft7l /
if(ps!=null) { DoA f,9|_
ps.clearParameters(); aQuENsB
ps.close(); gUlZcb
ps=null; E.brQx#}
} A,@"(3
}catch(SQLException e){} ~-x\E#(
DBUtils.closeConnection(conn); $@X,J2&
} eyOAG4QTV
} f}A^rWO
public long getLast(){ Px`yD3
return lastExecuteTime; GfV9Ox
} LE"xZxe
public void run(){ -lHJ\=
long now = System.currentTimeMillis(); >"b"K{t
if ((now - lastExecuteTime) > executeSep) { O4{&B@!
//System.out.print("lastExecuteTime:"+lastExecuteTime); O1PdM52
//System.out.print(" now:"+now+"\n"); "wc $'7M
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
~j_H2+!
lastExecuteTime=now; dx#N)?
executeUpdate(); $U1'n@/J
} ^;e`ZtcI
else{ /on p<u
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Fwtwf{9I
} ~Km8-b(&
} $vd._j&
} a&JAF?k
//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 0nX5
$Kn
%"tf`,d~3
类写好了,下面是在JSP中如下调用。 gxiJ`.D=
sz5@=
<% ! JN@4
CountBean cb=new CountBean(); XT\;2etVL
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); &yuerNK
CountCache.add(cb); Oc1ZIIkh\
out.print(CountCache.list.size()+"<br>"); BC^WPr
CountControl c=new CountControl(); lsd\ `X5,
c.run(); (s*}=
out.print(CountCache.list.size()+"<br>"); QLn5:&
%>