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: B}[CU='P*
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CountBean.java 1$RJzHS
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/* ILr=<j
* CountData.java +-tFg XG
* pW+uVv,
* Created on 2007年1月1日, 下午4:44 ]x)!Kd2>
* rC@VMe|0
* To change this template, choose Tools | Options and locate the template under pZ8J\4+
* the Source Creation and Management node. Right-click the template and choose G:*vV#K
* Open. You can then make changes to the template in the Source Editor. OROvy
*/ 1v&!%9
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package com.tot.count; 7R:j^"I@
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/** LqYyIbsvf
* Tdh(J",d
* @author {|>'(iqH"w
*/ +yI$4MY
public class CountBean { Muwlehuq
private String countType; C u`
int countId; # fqrZ9:@
/** Creates a new instance of CountData */ TG;[,oa
public CountBean() {} Q
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public void setCountType(String countTypes){ G,>YzjMY`
this.countType=countTypes; \k5"&]I3
} +a39 !j
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public void setCountId(int countIds){ gcnX^[`S
this.countId=countIds; * WV=X p
} .xqi7vVHZ
public String getCountType(){ nA0%M1a
return countType; .@fA_8
} mrr]{K
public int getCountId(){ ]I)ofXu]
return countId; L\UPM+tE
} X<5fn+{]S:
} oeg
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CountCache.java *%/O (ohs@
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/* D\G.p |9=
* CountCache.java /a*){JQ5j
* F. U@8lr
* Created on 2007年1月1日, 下午5:01 $B8Vg `+
* j4,y+9U
* To change this template, choose Tools | Options and locate the template under !Ew
ff|v"
* the Source Creation and Management node. Right-click the template and choose p-IJ':W
* Open. You can then make changes to the template in the Source Editor. .1TuHC\mC
*/ W`PJflr|
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package com.tot.count; 9h|6"6
import java.util.*; |!]
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/** fV4rVy8
* z'l
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* @author ~;9n6U
*/ HnArj_E
public class CountCache { Btxtu"]nJo
public static LinkedList list=new LinkedList(); |kK5:\H
/** Creates a new instance of CountCache */ tTBDb
public CountCache() {} WP*}X7IS
public static void add(CountBean cb){ tx7 zG.,
if(cb!=null){ 2*Qi4%s#
list.add(cb); /69yR
} RWv4/=}(G
} ?PWg
} 6YU,>KP
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CountControl.java ,r*Kxy
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/* vYm-$KQ"o
* CountThread.java 9HO9>^
* L9O;K$[s
* Created on 2007年1月1日, 下午4:57 |`
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* ^+Nd\tp
* To change this template, choose Tools | Options and locate the template under \t)va:y
* the Source Creation and Management node. Right-click the template and choose )YgntI@
* Open. You can then make changes to the template in the Source Editor. +z nlf-
*/ F oC
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package com.tot.count; WYb}SI(E
import tot.db.DBUtils; }Q4Vy
import java.sql.*; kr+p&|.
/** Uk] jy>7;!
* V<#KFm$>C
* @author )1!<<;@0
*/ lS9S7`
public class CountControl{ @=l6zd@
private static long lastExecuteTime=0;//上次更新时间 ~(v5p"]dj
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 HSysME1X:/
/** Creates a new instance of CountThread */ tkZUjQIX
public CountControl() {} w^Y/J4 I0
public synchronized void executeUpdate(){ <L8|Wz
Connection conn=null; EtzSaB*|
PreparedStatement ps=null; yVnG+R&
try{ !*Is0``
conn = DBUtils.getConnection(); k*?T^<c3
conn.setAutoCommit(false); D&pn@6bB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @Pk<3.S0
for(int i=0;i<CountCache.list.size();i++){ B>c$AS\5y
CountBean cb=(CountBean)CountCache.list.getFirst(); {,JO}Dmu5
CountCache.list.removeFirst(); Mq<ob+
ps.setInt(1, cb.getCountId()); <c[\\
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ps.executeUpdate();⑴ N$kxf
//ps.addBatch();⑵ (9RfsV4^
} 7:olStK
//int [] counts = ps.executeBatch();⑶ %B\x
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conn.commit(); 3as=EYm
}catch(Exception e){ Hh Q0>
e.printStackTrace(); j~>{P=_}
} finally{
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try{ :=y5713
if(ps!=null) { zEU[u7%
ps.clearParameters(); Q&.uL}R
ps.close(); 0zNbux_
ps=null; @\w}p E
} {)"[_<
}catch(SQLException e){} V3ozaVk;
DBUtils.closeConnection(conn); u ,3B[
} y:98}gW`n
} AC1RP`c
public long getLast(){ \4wMv[;7
return lastExecuteTime; #dae^UjM
} uKAI->"
public void run(){ <~5O-.G]
long now = System.currentTimeMillis(); F:q4cfL6
if ((now - lastExecuteTime) > executeSep) { D%]S>g5k
//System.out.print("lastExecuteTime:"+lastExecuteTime); _cQ
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//System.out.print(" now:"+now+"\n"); is8i_FoD,n
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `{:Nt#7
lastExecuteTime=now; " Bx@(
executeUpdate(); GIzB1cl:
} Op-z"inw
else{ (*$F7oO<
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2pdeJ
} ]Z5m_-I
} R ?iCJ5 m
} Qz(2Iu{E]
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 KV$&qM.
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类写好了,下面是在JSP中如下调用。 TiI /I`A
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<% 8^}/T#l
CountBean cb=new CountBean(); {WV"]O8IV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); N_bgW QY
CountCache.add(cb); Xd%qebK
out.print(CountCache.list.size()+"<br>"); \ji\r ]k
CountControl c=new CountControl(); N_K9H1r
c.run(); 7*uN[g#p
out.print(CountCache.list.size()+"<br>"); I}bu
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