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: yOE N*^6
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CountBean.java *7K)J8kq
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/* U_AmRiy
* CountData.java g/OL^A
* 92g&,Wb
* Created on 2007年1月1日, 下午4:44 hA387?
* Te@=8-u-
* To change this template, choose Tools | Options and locate the template under )Q c>NF0
* the Source Creation and Management node. Right-click the template and choose 9FmX^t$T
* Open. You can then make changes to the template in the Source Editor. b0[H{q-z{X
*/ v:u=.by99
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package com.tot.count; 5j#XNc)"
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/** |"k+j_/+
* 6q@VkzF
* @author ;1>)p x**
*/ HsAKz]Mq
public class CountBean { H6i;MQ
private String countType; R2dCp|6A
int countId; kqp*o+Oz',
/** Creates a new instance of CountData */ |H4f&&Wd
public CountBean() {} VB@M=ShKK
public void setCountType(String countTypes){ ( 2i{8
this.countType=countTypes; %<;PEQQ|C
} o|c%uw
public void setCountId(int countIds){ H]&^>Pvh
this.countId=countIds; 8aa`0X/6
} /PgcW
public String getCountType(){ H+Se
return countType; (-esUOB.
}
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public int getCountId(){ 5/4q}U3
return countId; rWxQ;bb#
} Bey|f/
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} Wf5ohXm>
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CountCache.java hT[w" &3
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/* +<\.z*
* CountCache.java FAF+ }
* T`SpIdzB.
* Created on 2007年1月1日, 下午5:01 k)B]|,g7G0
* >e9xM Gv
* To change this template, choose Tools | Options and locate the template under "CF{Mu|Q=
* the Source Creation and Management node. Right-click the template and choose qn#f:xltu
* Open. You can then make changes to the template in the Source Editor. VXIB9
/*i
*/ Yp8GW1@
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package com.tot.count; fv?vfI+m
import java.util.*; ~6O<5@k
/** 7W `gN[*
* K*fh`Kz
* @author `=VN\W^&
*/ <jHo2U8/"s
public class CountCache { o%$'-N
public static LinkedList list=new LinkedList(); rT{+ h}vO
/** Creates a new instance of CountCache */ DXc3u^
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public CountCache() {} 2JS&zF
public static void add(CountBean cb){ <t)D`nY\
if(cb!=null){ WR@TH
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list.add(cb); @G:aW\Z
} 8@-
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} ^Yu%JCN8g
} 2'5%EQW;0y
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CountControl.java fC^POLn[f
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/* @"gWvs
* CountThread.java S6bW?8`
* <zh N7="
* Created on 2007年1月1日, 下午4:57 #JIh-h@
* v35=4>Y
* To change this template, choose Tools | Options and locate the template under '+*{u]\
* the Source Creation and Management node. Right-click the template and choose c2d=dGP>~f
* Open. You can then make changes to the template in the Source Editor. UA]U_P$c
*/ tf_<w?~
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package com.tot.count; UgjY
import tot.db.DBUtils; 5
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import java.sql.*; -=CZhp
/** o9#8q_D9
* t?<pyw $
* @author Y6r<+#V
*/ \OX;ZVb?5
public class CountControl{ F;;\I
private static long lastExecuteTime=0;//上次更新时间 I#U"DwM
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 }Uc)iNU
/** Creates a new instance of CountThread */ oz[:
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public CountControl() {} 9j~|m
public synchronized void executeUpdate(){ E+xC1U
3
Connection conn=null; J52- qR/
PreparedStatement ps=null; l'0fRQc
try{ sp'f>F2]
conn = DBUtils.getConnection(); m0zbG1OE
conn.setAutoCommit(false); Wz]ny3K[.
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 1L\\](^
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for(int i=0;i<CountCache.list.size();i++){ x vx+a0 A
CountBean cb=(CountBean)CountCache.list.getFirst(); s8
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CountCache.list.removeFirst(); [~#]p9|L
ps.setInt(1, cb.getCountId()); F vt5vQ
ps.executeUpdate();⑴ wz{]CQ 7"
//ps.addBatch();⑵ eW>Y*l%B
} r[}5<S Q
//int [] counts = ps.executeBatch();⑶ Y3RaR
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conn.commit(); 8Z:T.Gc
}catch(Exception e){ Sdn4y(&TP
e.printStackTrace(); RC>79e/u<
} finally{ /3mt=1/~{B
try{ EiP#xjn?c
if(ps!=null) { SZ'2/#R>
ps.clearParameters(); _2N7E#m" S
ps.close(); y>YQx\mK
ps=null; +J<igb!S
} PUJkC
}catch(SQLException e){} y(w&6:
DBUtils.closeConnection(conn); Hk8pKpn3
} GjD^\d/
} 4gkaCk{]
public long getLast(){
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return lastExecuteTime; lI"~*"c`
} 8pZGu8
public void run(){ / 80Q
long now = System.currentTimeMillis(); |k ]{WCD]
if ((now - lastExecuteTime) > executeSep) { pDloew
//System.out.print("lastExecuteTime:"+lastExecuteTime); Op2@En|d
//System.out.print(" now:"+now+"\n"); j{?ogFfi
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Q]v><
lastExecuteTime=now; z +NwGVk3
executeUpdate(); oM~;du
} LI`H,2Km
else{ <T|?`;K
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7i@vj7K
} (n+FEE<
} 6hX[5?}
} ={]tklND
//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 {I:nza
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类写好了,下面是在JSP中如下调用。 a2!;$B%
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<% bAVlL&^@|
CountBean cb=new CountBean(); ]?3-;D.eG
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 3UX/
CountCache.add(cb); ~(~
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out.print(CountCache.list.size()+"<br>"); EK=PY
CountControl c=new CountControl(); KW 78J~u+
c.run(); \zMx~-2oN
out.print(CountCache.list.size()+"<br>"); $ctpg9 7
%>