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: Z[ 53cVT^
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CountBean.java 1 u~Xk?
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/* ;RW0Dn)Q
* CountData.java I^GZ9@UE
* Fa0NHX2:
* Created on 2007年1月1日, 下午4:44 17E,Qnf
* Z1~`S!(}
* To change this template, choose Tools | Options and locate the template under Q)/oU\
* the Source Creation and Management node. Right-click the template and choose WvoJ^{\4N*
* Open. You can then make changes to the template in the Source Editor. R:5uZAx
*/ 6/dP)"a('
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package com.tot.count; s~NJy'Y
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/** :|HCUZ*H(T
* )p`zN=t
* @author <~bvfA=
*/ ;%Zu[G`C
public class CountBean { Z#t}yC%^d
private String countType; ,$+ P
int countId;
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/** Creates a new instance of CountData */ hnnVp_<]
public CountBean() {} &5y|Q?
public void setCountType(String countTypes){ rYCIU
this.countType=countTypes; df)S}}#H
} 3Viz0I<%
public void setCountId(int countIds){ rqWD#FB=z
this.countId=countIds; e9;5.m
} j,79G^/YG
public String getCountType(){ NX&Z=ObHu}
return countType; 6hO]eS
} S}3?
public int getCountId(){ c6Z"6-}$
return countId; s$Vz1B
} ZA7b;{o [
} W_L;^5Y;m
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CountCache.java r'<!wp@
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/* NtG^t}V
* CountCache.java `D? &)Y
* #G]g
* Created on 2007年1月1日, 下午5:01 O%1uBc
* T(=Z0M
* To change this template, choose Tools | Options and locate the template under EX/{W$
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* the Source Creation and Management node. Right-click the template and choose sZ>0*S
* Open. You can then make changes to the template in the Source Editor. 6Qn};tbnD
*/ nC}Y+_wo0
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package com.tot.count; >x*ef]aS
import java.util.*; f+%s.[;A
/** Ys>Z=Eky
* w\1K.j=>|N
* @author LO;6g~(1
*/ xz-?sD/xe
public class CountCache { Sg<
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public static LinkedList list=new LinkedList(); 6J<R;g23R]
/** Creates a new instance of CountCache */ *o=[p2d"X
public CountCache() {} &9EcgazV
public static void add(CountBean cb){ ]Jnrs
if(cb!=null){ W+i&!'
list.add(cb); Y^QG\6q
} 3~\,VO''
} H}cq|hodn
} b"y4-KV
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CountControl.java {XH3zMk[
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/* K2gF;(
* CountThread.java Z4dl'v)9
* pwVaSnre`
* Created on 2007年1月1日, 下午4:57 BUUc9&f3o
* =@P]eK/
* To change this template, choose Tools | Options and locate the template under I&f!>y?,Z
* the Source Creation and Management node. Right-click the template and choose G4^6o[ x
* Open. You can then make changes to the template in the Source Editor. i|xC#hV
*/ 0D/7X9xg9+
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package com.tot.count; |qf ef&
import tot.db.DBUtils; bh+m_$X~
import java.sql.*; pB0 SCS*
/** :pLaxWus!
* EGzlRSgO
* @author A3.*d:A
*/ n^Q-K}!T/
public class CountControl{ O jH"qi
private static long lastExecuteTime=0;//上次更新时间 s;#,c(
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 UHS"{%
/** Creates a new instance of CountThread */ K$wxiGg8P
public CountControl() {} 6GoQJ
public synchronized void executeUpdate(){ @CS%=tE}U
Connection conn=null; #kgLdd"
PreparedStatement ps=null; ;( (|0Xa
try{ \s6VOR/
conn = DBUtils.getConnection(); J;N\q
conn.setAutoCommit(false);
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); JvF0s}#4
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); deOk>v&U
CountCache.list.removeFirst(); IM_SZs
ps.setInt(1, cb.getCountId()); M%OUkcWCk
ps.executeUpdate();⑴ ZyV^d3F@$
//ps.addBatch();⑵ 13A~."b
} jd.w7.8
//int [] counts = ps.executeBatch();⑶ X2`n&JE
conn.commit(); oK3PA
}catch(Exception e){ s=Xg6 D
e.printStackTrace(); Ap> H-/C
} finally{ l6N"{iXU
try{ SP;1XXlL
if(ps!=null) { aWY#gI{
ps.clearParameters(); k{ulu
ps.close(); ]f6,4[
ps=null; }[y_Fr0
} h7PIF*7m
e
}catch(SQLException e){} >$7{H]
DBUtils.closeConnection(conn); ,WE2MAjhT
} 1]&{6y
} NCVhWD21|
public long getLast(){ C8 y[B1Y
return lastExecuteTime; 4!A(7
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} 19i=kdH
public void run(){ 0GQKM~|H
long now = System.currentTimeMillis(); _sQhD i
if ((now - lastExecuteTime) > executeSep) { or(P?Ro
//System.out.print("lastExecuteTime:"+lastExecuteTime); qmtH0I7)
//System.out.print(" now:"+now+"\n"); Y?%=6S
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 2]E i4%jo
lastExecuteTime=now; $U'*}S
executeUpdate(); <m*j1|^{t
} `We?j7O
else{ 6 )lWuY]e
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'OU`$K7n
} zor
} 6%MM)Vj+u
} Wu)An
//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 SqVh\Nn
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类写好了,下面是在JSP中如下调用。 _pkmHj(
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<% 7)BK&kpVr
CountBean cb=new CountBean(); fr&K^je\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Sc:)H2k`$
CountCache.add(cb); EJ(z]M`f
out.print(CountCache.list.size()+"<br>"); NW`Mc&
CountControl c=new CountControl(); /}S1e P6
c.run(); V]/$ dJ
out.print(CountCache.list.size()+"<br>"); :/6u*HwZh
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