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: .Kb3VNgwvm
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CountBean.java XnyN*}8
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/* za_b jE
* CountData.java 3z8i0
* +hyOc|5
* Created on 2007年1月1日, 下午4:44 UY',n,
* |[*Bn3E:
* To change this template, choose Tools | Options and locate the template under c7e,lgG-
* the Source Creation and Management node. Right-click the template and choose Pxlc RF
* Open. You can then make changes to the template in the Source Editor. ']M/'CcM
*/ 5C Dk5B_
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package com.tot.count; _'=,c"
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/** b,xZY1a
* y\?ey'o
* @author aB,-E>+
*/ \Vyys[MMY8
public class CountBean { /LD3Bb)O
private String countType; 5n@YNaoIb
int countId; GcBqe=/B!
/** Creates a new instance of CountData */ KdVKvs[
public CountBean() {} ,d#*i
public void setCountType(String countTypes){ M>AxVL
this.countType=countTypes; XNz+a|cF
} q/i2o[f'n
public void setCountId(int countIds){ 6D;N.wDZ
this.countId=countIds; B~]Kqp7yU
} :`bC3Mr
public String getCountType(){ owAO&"C
return countType; H[=\_X1o(
} 5ya9VZ5#
public int getCountId(){ Kj4/fB
return countId; o<G 9t6~
} *8}b&4O~
} a|ufm^F
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CountCache.java 1dH|/9
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/* (@?mm
* CountCache.java ":!$Jnj,
* m^A2
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* Created on 2007年1月1日, 下午5:01 '/d51
* R<|\Z@z
* To change this template, choose Tools | Options and locate the template under aacy5E
* the Source Creation and Management node. Right-click the template and choose 78&|^sq
* Open. You can then make changes to the template in the Source Editor. 0Hnj<| HL
*/ :j\7</uu
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package com.tot.count; n
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import java.util.*; u?^V4 +V
/** eaw!5]huu
* e5L+NPeM6v
* @author P>/:dt'GJ}
*/ h@,ja
public class CountCache { iE%" Q? Q/
public static LinkedList list=new LinkedList(); v rs
/** Creates a new instance of CountCache */ VPMu)1={:p
public CountCache() {} !>`Q]M`
public static void add(CountBean cb){ R5HT
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if(cb!=null){ 9CDei~
list.add(cb); X 4;U4pU#
} MB]E[&Q!
} "{0G,tdA
} w\buQ6pR)
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CountControl.java T.bFB+'E|
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/* |$Yk)z3
* CountThread.java @*;x1A-]V
* g6M>S1oOO
* Created on 2007年1月1日, 下午4:57 -gn0@hS0
* <A3%182
* To change this template, choose Tools | Options and locate the template under g"-j/ c
* the Source Creation and Management node. Right-click the template and choose {oQs*`=l>
* Open. You can then make changes to the template in the Source Editor.
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*/ l}nV WuD
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package com.tot.count; &;PxDlY5
import tot.db.DBUtils; -E-#@s
import java.sql.*; dX[I
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/** Q'<AV1<
* , ZsZzZ#
* @author 6H#:rM
*/ Y\
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public class CountControl{ w{ja*F6
private static long lastExecuteTime=0;//上次更新时间 O& Y;/$w
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 UP](1lAf
/** Creates a new instance of CountThread */ |<W$rzM
public CountControl() {} /T _M't@j
public synchronized void executeUpdate(){ 1?'4%>kp
Connection conn=null; /~LE1^1&U
PreparedStatement ps=null; OUv )`K
try{ /|EdpHx0
conn = DBUtils.getConnection(); h.<f%&)F
conn.setAutoCommit(false); @?B+|*cm
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 9o@3$
for(int i=0;i<CountCache.list.size();i++){ '|C%X7
CountBean cb=(CountBean)CountCache.list.getFirst(); 4$-R|@,|_
CountCache.list.removeFirst(); HUKrp*Hv
ps.setInt(1, cb.getCountId()); 196aYLE
ps.executeUpdate();⑴ Wn<?_}sa|z
//ps.addBatch();⑵ BMp'.9Qgm
} C4m+Ta%
//int [] counts = ps.executeBatch();⑶ }dc0ZRKgx
conn.commit(); >}SEU-7&\
}catch(Exception e){ "L>'X22ed
e.printStackTrace(); jg$qp%7i%
} finally{ ^G4YvS(
try{ m?S;sew@5
if(ps!=null) { 4Kj.o
ps.clearParameters(); O-,
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ps.close(); z5@XFaQ
ps=null; :82T!
} 9#DXA}
}catch(SQLException e){} |/,SNE
DBUtils.closeConnection(conn); 45~x
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} !2t7s96
} Jm_)}dj3o
public long getLast(){ >LBA0ynh
{
return lastExecuteTime; &2ED<%hH`
} ]B/>=t"E
public void run(){ ,dRaV</2
long now = System.currentTimeMillis(); 6A"$9sj6
if ((now - lastExecuteTime) > executeSep) { f:-)S8OJ
//System.out.print("lastExecuteTime:"+lastExecuteTime); !Fl'?Kz
//System.out.print(" now:"+now+"\n"); B.N#9u-vW
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >axeUd+@i
lastExecuteTime=now; .IW`?9O$E
executeUpdate(); /
} M+ [ho]
else{ SVU>q:ab
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~b_DFj
} FJvY`zqB
}
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} |~Dl<#58
//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 mCO1,?
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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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<% u99a"+
CountBean cb=new CountBean(); +O/b[O'0
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 2yA)SGri
CountCache.add(cb); 2cCiHEL #
out.print(CountCache.list.size()+"<br>"); iil<zEic
CountControl c=new CountControl(); R4p Pt
c.run(); <-I69`
out.print(CountCache.list.size()+"<br>");
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%>