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: L@.Trso
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CountBean.java .|0$?w
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/* <Ok7-:OxA
* CountData.java }U?:al/m
* o1thGttVDg
* Created on 2007年1月1日, 下午4:44 [9yd29pQ]
* ]e$n ;tuW
* To change this template, choose Tools | Options and locate the template under 9<.8mW^68
* the Source Creation and Management node. Right-click the template and choose ?}HZJ@:lB
* Open. You can then make changes to the template in the Source Editor. G"ixw
*/ #'.
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package com.tot.count; NR"C@3kD]o
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/** 5b->pc
* %4})_h?j
* @author KQ0f2?
*/ udPLWrPF\
public class CountBean { pm2]
private String countType; ra8AUj~RX
int countId; $3xDjiBb
/** Creates a new instance of CountData */ h-fm)1S_
public CountBean() {} }\1V%c
public void setCountType(String countTypes){ Nz:p(X!
this.countType=countTypes; P!gY&>EU
} |@VhR(^O$
public void setCountId(int countIds){ Y.kc,~vYL
this.countId=countIds; /#j)GlNp:
} ` 5n^DP*X
public String getCountType(){ SeuDJxqopD
return countType; !&5|:96o
} 89t"2|9 u
public int getCountId(){ /Mj|Px%
return countId; 2fXwJG'
} 5 BeU/
} {\X$vaF
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CountCache.java 0^)~p{Zh
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/* G?!8T91;
* CountCache.java %S^:5#9
* AC!yc(^<
* Created on 2007年1月1日, 下午5:01 nI] zRduC
* S5r.so
* To change this template, choose Tools | Options and locate the template under N*\ri0
* the Source Creation and Management node. Right-click the template and choose } ?MbU6"
* Open. You can then make changes to the template in the Source Editor. +BE_t(%p"
*/ n4.\}%=z
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package com.tot.count; "whs?^/
import java.util.*; fcy4?SQ.<i
/** /N,\ st
* ,eSpt#M
* @author 7jGfQ
*/ 0}po74x*r
public class CountCache { v^ v \6uEP
public static LinkedList list=new LinkedList(); At!@Rc
/** Creates a new instance of CountCache */ ) )t]5Ys%;
public CountCache() {} %'VzN3Q5V
public static void add(CountBean cb){ ^1<i7u
if(cb!=null){ I9xkqj
list.add(cb); ?!.J0q
} bdEIvf7
} lq a~ZF*
} yqR]9"a
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CountControl.java x$FcF8
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/* wk'&n^_br
* CountThread.java d.
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* L-zU%`1{M
* Created on 2007年1月1日, 下午4:57 7Sh1QDYZ
* tKds|0,j|
* To change this template, choose Tools | Options and locate the template under CWJN{
* the Source Creation and Management node. Right-click the template and choose f{uS
* Open. You can then make changes to the template in the Source Editor. ;f=.SJF
*/ GL,[32~C
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package com.tot.count; ^z~drcR
import tot.db.DBUtils; 1 |/ |Lq%w
import java.sql.*; h")7kjM
/** \7%wJIeyx
* HVzkS|^F
* @author Aj(y]p8
*/ LBmXy8'T`
public class CountControl{ fPstSez
private static long lastExecuteTime=0;//上次更新时间 F!w|5,)
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 KTwP.!<v
/** Creates a new instance of CountThread */ GkI{7GD:z
public CountControl() {} s3'kzwX
public synchronized void executeUpdate(){ Fc=6*.hy
Connection conn=null; 7]~|dc(
PreparedStatement ps=null; @Kw&XK e`
try{ {,?Gj@$
conn = DBUtils.getConnection(); (y1S*_D
conn.setAutoCommit(false); KHGUR(\Rd6
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); )*Wz5x
for(int i=0;i<CountCache.list.size();i++){ LI^D\
CountBean cb=(CountBean)CountCache.list.getFirst(); -BWWaL
CountCache.list.removeFirst(); cl |}0Q5
ps.setInt(1, cb.getCountId()); "xn,'`a
ps.executeUpdate();⑴ S~&9DQNj
//ps.addBatch();⑵ 8iM:ok
} =kCiJ8q|
//int [] counts = ps.executeBatch();⑶ }^P"R[+4u
conn.commit(); 2|U6dLZ!
}catch(Exception e){ E,cQ9}/
e.printStackTrace(); A,(9|#%L
} finally{ r;E5e]w*-
try{ V#R; -C
if(ps!=null) { ZI8@ 6 L\
ps.clearParameters(); /!y;h-
ps.close(); P#
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ps=null; lHHx D
} px(~ZZB"
}catch(SQLException e){} Lr(JnS
DBUtils.closeConnection(conn); ="PFCxi
} XqwP<5Z
} .F[5{XV
public long getLast(){ d/awQXKe7
return lastExecuteTime; P0U&+^W"9
} E*kZGHA
public void run(){ C~'.3Q6
long now = System.currentTimeMillis(); ?^LG>GgV
if ((now - lastExecuteTime) > executeSep) { d`%7Pk
//System.out.print("lastExecuteTime:"+lastExecuteTime); b!teSf
//System.out.print(" now:"+now+"\n"); .[1@wW&L
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); *P&lAyt6
lastExecuteTime=now; g>`D!n::n
executeUpdate(); 8dJ+Ei~M
} c?aOX/C'
else{ jj]|}G
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); HiD%BL>%
} $BG]is,&5
} )J2UNIgN
} wF59g38[z$
//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 WP=uHg
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类写好了,下面是在JSP中如下调用。 <7zz"R
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<% /zr)9LQY0
CountBean cb=new CountBean(); _a_T`fE&de
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ;ZMIYFXRqh
CountCache.add(cb); P{Q$(rOe
out.print(CountCache.list.size()+"<br>"); *i!t&s
CountControl c=new CountControl(); 1u(n[<WtT_
c.run(); {Z
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out.print(CountCache.list.size()+"<br>"); IGab~`c-[
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