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: ~+S,`8-P
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CountBean.java ?*L{xNC#
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/* 1YScZ
* CountData.java ^y.|KA3[
* D%~"]WnZ\Q
* Created on 2007年1月1日, 下午4:44 au#/Q
* o3cE.YUF
* To change this template, choose Tools | Options and locate the template under *?rO@sQy]
* the Source Creation and Management node. Right-click the template and choose !QlCt>{
* Open. You can then make changes to the template in the Source Editor. wnjAiIE5
*/ ib%'{?Q.
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package com.tot.count; Vl/fkd,Z
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/** )(+q~KA}
* ~A_1he~
* @author {sW>J0
*/ -,q
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public class CountBean { ${{[g16X
private String countType;
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int countId; N{H#j6QW
/** Creates a new instance of CountData */ "#P#;]\ `
public CountBean() {} PIHKSAnq
public void setCountType(String countTypes){ zNM*xPgS
this.countType=countTypes; #xh
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} fyEXnmB;
public void setCountId(int countIds){ Uc9hv?
this.countId=countIds; pfQ3Y$z
} M>ntldV#g%
public String getCountType(){ g>QN9v})
return countType; M44$E4a20
} qNWSDZQ
public int getCountId(){ z\-/R9E/5-
return countId; rP IAu[],g
} LKgo(&mY
} Q%W>m0%
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CountCache.java 70{B/ ($
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/* yCwe:58
* CountCache.java xy]oj
* NH4T*R)Vz
* Created on 2007年1月1日, 下午5:01 &q +l5L"
* ;Kh?iqn^
* To change this template, choose Tools | Options and locate the template under p@ U[fv8u
* the Source Creation and Management node. Right-click the template and choose 0xH&^Ia1B
* Open. You can then make changes to the template in the Source Editor. +1^L35\@
*/ cNMDI
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package com.tot.count; 9W&nAr
import java.util.*; &t6:1 T
/** Sa@T#%oU
* ?kS#g
* @author pJIJ"o'>.9
*/ -/:K.SY,
public class CountCache { _k#GjAPM
public static LinkedList list=new LinkedList(); e/x6{~ju^N
/** Creates a new instance of CountCache */ na@Go@q
public CountCache() {} n<1*cL:8B
public static void add(CountBean cb){ |Mgzb0_IiQ
if(cb!=null){ 39L_O RMH
list.add(cb); :<HLw.4O
} S0ltj8t
} Z29LtKr
} Vi>P =i
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CountControl.java +
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/* 'F3@Xh
* CountThread.java RKp9[^/?
* n@6vCdk.
* Created on 2007年1月1日, 下午4:57 \-sW>LIA
* ">MsV/
* To change this template, choose Tools | Options and locate the template under f4VdH#eng`
* the Source Creation and Management node. Right-click the template and choose J:OP*/@='
* Open. You can then make changes to the template in the Source Editor. 5 Pf)&iG
*/ MI-S}Qoe
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package com.tot.count; |T]&8Q)S
import tot.db.DBUtils; a^_W}gzzd
import java.sql.*; >v f-,B
/** (EjlnG}5l
* %<8r`BMo
* @author g~U<0+&yw%
*/ PXML1.r$Q
public class CountControl{ ZXXJ!9-&+J
private static long lastExecuteTime=0;//上次更新时间 HU$]o N
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 qJ2Z5
/** Creates a new instance of CountThread */ &[SFl{fx>-
public CountControl() {} #m;o)KkH$r
public synchronized void executeUpdate(){ )2# qi/
Connection conn=null; ?9>wG7cps7
PreparedStatement ps=null; /qMiv7m~Q
try{ Zrj#4E1
conn = DBUtils.getConnection(); w`fbUh6/
conn.setAutoCommit(false); tx)$4 v
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ?uU_N$x
for(int i=0;i<CountCache.list.size();i++){ FHEP/T\5
CountBean cb=(CountBean)CountCache.list.getFirst(); M8$eMS1
CountCache.list.removeFirst(); ; 6PRi/@
ps.setInt(1, cb.getCountId()); w'XN<RWA
ps.executeUpdate();⑴ L=fy!R
//ps.addBatch();⑵ Lf%=vd
} n5;@}Rai
//int [] counts = ps.executeBatch();⑶ U| ?68B3
conn.commit(); VMe
}catch(Exception e){ ;?q}98-2
e.printStackTrace(); FnI}N;"
} finally{ IP@3R(DS%
try{ [9V}>kS)
if(ps!=null) { z30 mk
ps.clearParameters(); |QMmF" 0
ps.close(); !YI<A\P
ps=null; C`.eJF
} [zXC\)&!
}catch(SQLException e){} 2`j{n\/
DBUtils.closeConnection(conn); cP\z*\dS
} gs=ok8w
} <&2<>*/.y
public long getLast(){ ofw&?Sk0
return lastExecuteTime; H_Va$}8z
} Dsn=fht
public void run(){ 9Kgyt
long now = System.currentTimeMillis(); d{t@+}0.u
if ((now - lastExecuteTime) > executeSep) { >B=s+}/ME
//System.out.print("lastExecuteTime:"+lastExecuteTime); #sBL E
//System.out.print(" now:"+now+"\n"); jSH.e?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); H9i7y,[*
lastExecuteTime=now; !]Qk?T~9-
executeUpdate(); !M`.(sO]
} J/:U,01
else{ S=.%aB
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); V6'u\Ch|
} fR~0Fy Gp
} Q672iR\#)
} N)Q.P'`N
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 L N.:>,
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类写好了,下面是在JSP中如下调用。 ]7>#YKH.
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<% 3$q#^UvD
CountBean cb=new CountBean(); Yw]$/oP`
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); x?lRObHK
CountCache.add(cb); 9S[.ESI{>
out.print(CountCache.list.size()+"<br>"); "
DLIx}
CountControl c=new CountControl(); <8Tp]1z
c.run(); 54JZOtC3~
out.print(CountCache.list.size()+"<br>"); 7SH3k=x
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