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{GLP?H
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CountBean.java M:+CW;||!
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/* KOcB#UHJ
* CountData.java Bkcwl
* z*.AuEK?
* Created on 2007年1月1日, 下午4:44 aKI"<%PNn
* ,.,8-In^
* To change this template, choose Tools | Options and locate the template under iJs~NLCgVu
* the Source Creation and Management node. Right-click the template and choose {:X'9NEE
* Open. You can then make changes to the template in the Source Editor. }d[(kC_
*/ ^FVdA1~/
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package com.tot.count; y{<e4{
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/** $WA wMS,
* !>`Q]M`
* @author mF7Ak&So^
*/ G~9m,l+
public class CountBean { ]2AOW}=
private String countType; @Z5q2Q
int countId; k/K)nH@)
/** Creates a new instance of CountData */ RX gb/VR
public CountBean() {} AWO)]rM
public void setCountType(String countTypes){ [txOh!sxD
this.countType=countTypes; #CS>_qe.{
} 77RZ<u9/`
public void setCountId(int countIds){ wh:;G`6S
this.countId=countIds; .LzA'q1+z
} te@m#`p9
public String getCountType(){ T;w:^XW
return countType; [,=?e
} }M07-qIX{
public int getCountId(){ d4Uw+3ikW
return countId; OSu&vFKz
} >M<3!?fW)
} <8r"QJY/
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CountCache.java +B? qx
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/* K@.5
* CountCache.java Cfi{%,em
* Jh"[ug
* Created on 2007年1月1日, 下午5:01 oo'9ZE/%
* =
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* To change this template, choose Tools | Options and locate the template under )nN!% |J
* the Source Creation and Management node. Right-click the template and choose XC<fNK
* Open. You can then make changes to the template in the Source Editor. >"W^|2R
*/ /}:{(Go
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package com.tot.count; >y%H2][
import java.util.*; g~U(w
/** {yn,u)@r9S
* , ZsZzZ#
* @author yF)o_OA[uR
*/ j\}.GM'8
public class CountCache { Y\
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public static LinkedList list=new LinkedList(); Aztrq
/** Creates a new instance of CountCache */ $|$@?H>K
public CountCache() {} J8'"vc} =
public static void add(CountBean cb){ .f~9IAXP`
if(cb!=null){ =*UK!y?n
list.add(cb); !BQt+4G7
} j0l,1=^>l
} t3L>@NWG
} @c~Z0+Ji
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CountControl.java
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/* Ah2@sp,z
* CountThread.java **q8vhJM
* @?B+|*cm
* Created on 2007年1月1日, 下午4:57 h,LSqjf"
* 5U84*RY
* To change this template, choose Tools | Options and locate the template under U,rI/'
* the Source Creation and Management node. Right-click the template and choose J(1Tl
* Open. You can then make changes to the template in the Source Editor. (-C)A-Uo&
*/ A 3 V
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package com.tot.count; {;$oC4
import tot.db.DBUtils; jz!I +
import java.sql.*; GQ(Y#HSq
/** jCqz^5=$
* teok *'b:
* @author J/]%zwDwS
*/ %"
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public class CountControl{ }dc0ZRKgx
private static long lastExecuteTime=0;//上次更新时间 A
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6wlLE5
/** Creates a new instance of CountThread */ &h:4TaD
public CountControl() {} Bii'^^I;?
public synchronized void executeUpdate(){ !vz'zy)7
Connection conn=null; hFV,FBsAO
PreparedStatement ps=null; r S@/@jKZE
try{ [6VB&
conn = DBUtils.getConnection(); Z`TfS+O6
conn.setAutoCommit(false); 1/$PxQ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); -2hirA<^
for(int i=0;i<CountCache.list.size();i++){ c>bns/f
CountBean cb=(CountBean)CountCache.list.getFirst(); b9H(w%7ucU
CountCache.list.removeFirst(); :82T!
ps.setInt(1, cb.getCountId()); #:6-O
ps.executeUpdate();⑴ 7Ae`>5B#
//ps.addBatch();⑵ X,Ql6uO
} D||0c"E
//int [] counts = ps.executeBatch();⑶ LOU P
conn.commit(); BlJiHz!
}catch(Exception e){ p4T$(]7
e.printStackTrace(); Jm_)}dj3o
} finally{ '_v~+
try{ V%-hP~nyBx
if(ps!=null) { V60L\?a
ps.clearParameters(); Q[OwP
ps.close(); .`D'eS6b
ps=null; ItVN,sVJb
} fD!c t; UK
}catch(SQLException e){} p%I)&- 8
DBUtils.closeConnection(conn); N[Z`tk?-
} lY,^
} eo+<@83
public long getLast(){
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return lastExecuteTime; jE0oLEg&
} ^Iw$(
public void run(){ Sz5t~U=G
long now = System.currentTimeMillis(); $>)0t@[f
if ((now - lastExecuteTime) > executeSep) { 7.
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//System.out.print("lastExecuteTime:"+lastExecuteTime); [CQR
//System.out.print(" now:"+now+"\n"); oN032o?S
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); TgkVd]4%
lastExecuteTime=now; 6]7csOE
executeUpdate(); .SC*! ,
} xs= ~N
else{ 7I3_$uF
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <Km9Mq
} 4 OPY
} *'((_NZ>
} '#6eUb
//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 sVyV|!K
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类写好了,下面是在JSP中如下调用。 u=:f%l
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<% bZ*=fdh
CountBean cb=new CountBean(); u99a"+
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _xKn2 ?d8g
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); F`g(vD>
CountControl c=new CountControl(); H07\z1?.K
c.run(); ?V6,>e_+
out.print(CountCache.list.size()+"<br>"); K P]ar.
%>