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: c'XvZNf .C
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CountBean.java Shm$>\~=
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/* iYE7BUH=
* CountData.java uK_R#^
* ,Q2?Z:l
* Created on 2007年1月1日, 下午4:44 OZ9ud ]@\
* r@.3.Q
* To change this template, choose Tools | Options and locate the template under 9cO
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* the Source Creation and Management node. Right-click the template and choose ~ ZN]2}
* Open. You can then make changes to the template in the Source Editor. O*:8gu'Y2
*/ 1/l;4~p7'
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package com.tot.count; c'LDHh7b
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/** TlA*~HG<Q
* iax6o+OG|
* @author F\H^=P
*/ Jm5&6=
public class CountBean { bTrQ(qp
private String countType; -2\%?A6L
int countId; j0]|$p
/** Creates a new instance of CountData */ `O'@TrI
public CountBean() {} fho$:S
public void setCountType(String countTypes){ [tP6FdS/M=
this.countType=countTypes; \`MX\OR
} 1I1Z),
public void setCountId(int countIds){ <.l$jW]
this.countId=countIds; >.fN@8[
} sA}X ha
public String getCountType(){ [:MpOl-KIz
return countType; [|NgrU_.
} <jnra4>
public int getCountId(){ rK@ UCRf
return countId; <"8<<
} eT4+O5t
} I {o\d'/
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CountCache.java \!_:<"nX.
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/* >d{O1by=d9
* CountCache.java }_A#O|dxO
* L+b"d3!G&%
* Created on 2007年1月1日, 下午5:01 jxt^d
* VHUOI64*
* To change this template, choose Tools | Options and locate the template under 'h:[[D%H`
* the Source Creation and Management node. Right-click the template and choose 4 <&8`Q
* Open. You can then make changes to the template in the Source Editor. 6$l6>A
*/ 2Q/#.lNL
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package com.tot.count; eL7rX"!
import java.util.*; sHr!GF
/** *YhX6J1
* 8r 4
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* @author qZ8V/
*/ yzml4/X
public class CountCache { o (OC3
public static LinkedList list=new LinkedList(); | gou#zi
/** Creates a new instance of CountCache */ 7T)J{:+0!|
public CountCache() {} pKM5<1J
public static void add(CountBean cb){ w,CZ*/^
if(cb!=null){ CLU[')H0
list.add(cb); ,iUYsY
} }: W6Bo-|
}
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} NyJ=^=F#
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CountControl.java d_5wMK6O6
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/* XP$ 1CWI
* CountThread.java -i}@o1o\
* b,7@)sZ*
* Created on 2007年1月1日, 下午4:57 9=-!~_'1-
* u}[Z=V
* To change this template, choose Tools | Options and locate the template under zg3q\~
* the Source Creation and Management node. Right-click the template and choose KLc<c1BZ
* Open. You can then make changes to the template in the Source Editor. P]pVYX#m
*/ r|bvpZV
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package com.tot.count; <AzM~]"3
import tot.db.DBUtils; 9bpY>ze
import java.sql.*; 7;_./c_@
/** <( 0TK5
* u/D=&"tL
* @author d9hJEu!Lu
*/ 4~G++|NQ
public class CountControl{ X5@rPGc
private static long lastExecuteTime=0;//上次更新时间 CpAdE m{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 qX(sx2TK
/** Creates a new instance of CountThread */ 0CYm%p8!
public CountControl() {} ye9-%~sjX
public synchronized void executeUpdate(){ $X %w9le
Connection conn=null; 41595x:
PreparedStatement ps=null; FL5tIfV+
try{ Ve4!MM@ti
conn = DBUtils.getConnection(); LZ@4,Uj
conn.setAutoCommit(false); SGU~LW&
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); pGy]t
for(int i=0;i<CountCache.list.size();i++){ ?1I0VA']
CountBean cb=(CountBean)CountCache.list.getFirst(); Mb I';Mq
CountCache.list.removeFirst(); Tv;|K's'
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ 0%
//ps.addBatch();⑵ [-@Lbu-|
} FafOd9>AO
//int [] counts = ps.executeBatch();⑶ NA,)FmQjk
conn.commit(); kCRP?sj
}catch(Exception e){ | Wrf|%p
e.printStackTrace(); !/w<F{cl
} finally{ S*o%#ZJN
try{ p& > z=Z*
if(ps!=null) { v:YW[THre
ps.clearParameters(); ]hBp
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ps.close(); nnU
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ps=null; B=:7N;BT
} 6 ]@H .8+
}catch(SQLException e){} .[-d( #l{l
DBUtils.closeConnection(conn); C^po*(W6
} ?PIOuN=
} K"cN`Kj<*-
public long getLast(){ 8"a[W3b
return lastExecuteTime;
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} T
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public void run(){ ( _ZOUMe
long now = System.currentTimeMillis(); [Hn4&PET
if ((now - lastExecuteTime) > executeSep) { >
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//System.out.print("lastExecuteTime:"+lastExecuteTime); T(<C8
//System.out.print(" now:"+now+"\n"); (R*K)(Nw[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 3wEVjT-
lastExecuteTime=now; #:v e3gWl
executeUpdate(); -*sDa6L
} Ojx1IL
else{ +jFcq:`#UG
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); F*F
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} :[iWl8
} `0tzQ>ZQq
} TR8<=
//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 {XMF26C#
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类写好了,下面是在JSP中如下调用。 -d+q +l>0
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<% 7_WD)Y2yS
CountBean cb=new CountBean(); v1yNVs\}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); IYq)p
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CountCache.add(cb); 'IweN
out.print(CountCache.list.size()+"<br>"); :XK.A
CountControl c=new CountControl(); nf5Ld"|%9
c.run(); V`V
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out.print(CountCache.list.size()+"<br>"); yWa-iHWC
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