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: LsI@_,XW<
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CountBean.java #\N8E-d
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/* 1O,5bi>t7
* CountData.java 4E=QO!pVv
* v B~VJKD
* Created on 2007年1月1日, 下午4:44
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* 0?t;3z$n
* To change this template, choose Tools | Options and locate the template under ye(av&Hn
* the Source Creation and Management node. Right-click the template and choose ~pH!.|k-&
* Open. You can then make changes to the template in the Source Editor. sa<\nH$_X
*/ ;~r- P$kCY
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package com.tot.count; AXxyB"7A}
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/** &b,A-1`w_
* QsPg4y3?D
* @author f
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*/ r2tE!gMC
public class CountBean { xc-[gt6
private String countType; Qt\:A!'jw
int countId; UxB3/!<5g3
/** Creates a new instance of CountData */ 9G6ZKqum
public CountBean() {} ^PE|BCs
public void setCountType(String countTypes){ (qR;6l
this.countType=countTypes; \;_tXb}F
} IDpLf*vSG
public void setCountId(int countIds){ @g`|ob]9
this.countId=countIds; lxZ9y
} {4SaSv^/
public String getCountType(){ wAu]U6!
return countType; }+S~Ah?(
} q},,[t
public int getCountId(){ T1RY1hb|g>
return countId; v1+.-hO
} h8M_Uk
} wPYeKOh'
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CountCache.java HLthVc w
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/* _7u&.l<;
* CountCache.java E}%Pwr
* `=V1w4J
* Created on 2007年1月1日, 下午5:01 R)N^j'R~=
* SR.xI:}4
* To change this template, choose Tools | Options and locate the template under G3!O@j!7w$
* the Source Creation and Management node. Right-click the template and choose K5bR7f:
* Open. You can then make changes to the template in the Source Editor. ;H8`^;
*/ DfGq m-c
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package com.tot.count; !]7b31$M_
import java.util.*; jp}.W
/** ldU ><xc2
* ZvXw#0)v
* @author (7,Q4T
*/ c3rj
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public class CountCache { -sf[o"T,j
public static LinkedList list=new LinkedList(); iu{;|E
/** Creates a new instance of CountCache */ VR_/Vh]@
public CountCache() {} AK'3N1l`
public static void add(CountBean cb){ m=COF$<
if(cb!=null){ F#Pn]
list.add(cb); ">8oF.A^
} Je"XIhBr
} :qR8 e J
} N|"q6M!ZL
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CountControl.java E.N>,N
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/* 2|1CGHj\
* CountThread.java &'DR`e O)
* D8B\F5..c#
* Created on 2007年1月1日, 下午4:57 ]RadwH"0!
* >D##94PZ
* To change this template, choose Tools | Options and locate the template under h<'tQGC
* the Source Creation and Management node. Right-click the template and choose RxV
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* Open. You can then make changes to the template in the Source Editor. w .M
*/ i*4v!(E
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package com.tot.count;
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import tot.db.DBUtils; S}Z@g
import java.sql.*; 6v}q @z
/** 41.xi9V2
* X?u=R)uG
* @author Je^;[^
*/ is%ef
public class CountControl{ Xfb-<
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private static long lastExecuteTime=0;//上次更新时间 i8cmT+}>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 'tQp&pj
/** Creates a new instance of CountThread */ F!?f|z,/
public CountControl() {} N48X[Q*
public synchronized void executeUpdate(){ %/nDG9l
Connection conn=null; K'E)?NW69
PreparedStatement ps=null; v3n
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try{ KL(sVj^e
conn = DBUtils.getConnection(); zw5Ol%JF
conn.setAutoCommit(false); A'u]z\&%c
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); -m=!SQ >9
for(int i=0;i<CountCache.list.size();i++){ ?hp,h3s;n$
CountBean cb=(CountBean)CountCache.list.getFirst(); DtS7)/<T
CountCache.list.removeFirst(); jgEYlZ
ps.setInt(1, cb.getCountId()); 8/P!i2o
ps.executeUpdate();⑴ /UR;,ts
//ps.addBatch();⑵ "~K ph0-
} OYa9f[ $
//int [] counts = ps.executeBatch();⑶ Kxh WZ3
conn.commit(); z^/9YzA!6
}catch(Exception e){ 5YI6$ZdQ
e.printStackTrace(); L"T :#>
} finally{ eAQ-r\h'2
try{ Z)3oiLmD
if(ps!=null) { B'y)bY'_dS
ps.clearParameters(); :UKc:JVNM
ps.close(); 6 RSit
ps=null; G_k_qP^:
} z-]ND
}catch(SQLException e){} hVZS6gU,x
DBUtils.closeConnection(conn); 7a/
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} nI73E
} r4?|sAK
public long getLast(){ Nd;pkssd
return lastExecuteTime; ]_L;AD
} SFEDR?s
public void run(){ (A?w|/bZd
long now = System.currentTimeMillis(); KNF{NFk
if ((now - lastExecuteTime) > executeSep) { )C0Iy.N-
//System.out.print("lastExecuteTime:"+lastExecuteTime); uXA}" f2
//System.out.print(" now:"+now+"\n"); S]e;p\8$Z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {8;}y[R
lastExecuteTime=now; B1Z;
executeUpdate(); -" r4
} ]h`d>#Hw!
else{ z 7cA5'c
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); a=B $L6*4
} %82:?fq
} v[DxWs8q
} xj]^<oi<
//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 3^)c5kcI
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类写好了,下面是在JSP中如下调用。 3Zp q#
4 4WyfpTJ*
<% NUtKT~V
CountBean cb=new CountBean(); 1:|o7`
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Iy4REP|
CountCache.add(cb); (Dba!zSs
out.print(CountCache.list.size()+"<br>"); *u[@C
CountControl c=new CountControl(); /Ea&Zm
c.run(); mZnsr@KF
out.print(CountCache.list.size()+"<br>"); >V%.=})K
%>