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: F`nb21{0y&
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CountBean.java W23]Bx
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/* n,~;x@=5
* CountData.java !GW,\y
* [+w3J#K
* Created on 2007年1月1日, 下午4:44 [ BT)l]
* PY3ps2^K.
* To change this template, choose Tools | Options and locate the template under {B*W\[ns
* the Source Creation and Management node. Right-click the template and choose 0F#>CmD
* Open. You can then make changes to the template in the Source Editor. 4f~["[*ea
*/ F?m?UQS'u
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package com.tot.count; VR!-%H\AW
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/** }X;U|]d
* qn"D#K'&(
* @author `o79g"kxe
*/ XJ!(F#zc
public class CountBean { o{*ay$vA]
private String countType; G5D2oQa=8
int countId; CK_(b"
/** Creates a new instance of CountData */ *n(> ^
public CountBean() {} `]$?uQ
public void setCountType(String countTypes){ M+wt__vHf
this.countType=countTypes; sA9&/p/
} -ng=l;
public void setCountId(int countIds){ 8hA^`Y
this.countId=countIds; Fg/dS6=n`?
} wA`"\MWm
public String getCountType(){ gPzL*6OSA
return countType; NZu)j["
} 44\>gI<
public int getCountId(){ 7@a 0$coP
return countId; `>D9P_Y"jI
} ni
} aFY_:.o2k`
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CountCache.java #JA}3]
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/* XE}H 3/2
* CountCache.java }<MR`h1
* +:6Ii9GN
* Created on 2007年1月1日, 下午5:01 Lt#'W
* 5j"1z1_&
* To change this template, choose Tools | Options and locate the template under %lr|xX
* the Source Creation and Management node. Right-click the template and choose RA a[t :|
* Open. You can then make changes to the template in the Source Editor. 5/m$)wE
*/ <-UOISyf
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package com.tot.count; ^TXf sQs
import java.util.*; Swtbl`,
/** :9l51oE7
* \g-j9|0
* @author p4VqV6LwD
*/ LF*Q!
public class CountCache { |0bc$ZY:
public static LinkedList list=new LinkedList(); 2aw&F Z?
/** Creates a new instance of CountCache */ BbJkdt7
public CountCache() {} }tST)=M`
public static void add(CountBean cb){ ^T4Ay=~{
if(cb!=null){ ;52'}%5
list.add(cb);
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} km:nE: |
} H L<s@kEZ
} i(2y:U3[@
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CountControl.java {bF1\S]2
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/* }xn_6
* CountThread.java }bB`(B,m
* h3u1K>R)
* Created on 2007年1月1日, 下午4:57 ]_*S~'x
* ED![^=
* To change this template, choose Tools | Options and locate the template under ARh6V&Hi-
* the Source Creation and Management node. Right-click the template and choose OQlG+|
* Open. You can then make changes to the template in the Source Editor. KA]*ox6j;
*/ p4X{"Z\mn
=G-N`
39
package com.tot.count; 6k])Kl J2;
import tot.db.DBUtils; }4%/pOi:f
import java.sql.*; W^g[L:s
/** OCyG_DLT$5
* !UV5zmS
* @author J/D|4fC
*/ ),@f6](
public class CountControl{ /k:$l9C[
private static long lastExecuteTime=0;//上次更新时间 c"gsB!xh
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 00vBpsZj2;
/** Creates a new instance of CountThread */ "c`xH@D
public CountControl() {} xc'vS>&
public synchronized void executeUpdate(){ 1H4fJ3-
Connection conn=null; h.tY 'F
PreparedStatement ps=null; Q]JX`HgPaU
try{ o96:4j4
conn = DBUtils.getConnection(); ?Z %:
conn.setAutoCommit(false); S;@ay/*~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); EU`T6M
for(int i=0;i<CountCache.list.size();i++){ {_ V0
CountBean cb=(CountBean)CountCache.list.getFirst(); S0@T0y#
CountCache.list.removeFirst(); LZ~`29qw(
ps.setInt(1, cb.getCountId()); ~o15#Pfn/
ps.executeUpdate();⑴ SHdL/1~t
//ps.addBatch();⑵ b#Kq[}
} L&w.j0fq
//int [] counts = ps.executeBatch();⑶ =_=*OEgO]
conn.commit(); *:_~Nn9_R;
}catch(Exception e){ /Ic[N&
e.printStackTrace(); OHp5z?
z
} finally{ p6 xPheD
try{ v"1Po_`
if(ps!=null) { BD;H
ps.clearParameters(); zQuM !.
ps.close(); 2:v <qX
ps=null; @Jv# fr
} [ x>
}catch(SQLException e){} \SYvD y]
DBUtils.closeConnection(conn); LPE)
} "G?9b
} oh}^?p
public long getLast(){ ,jh~;, w2
return lastExecuteTime; *v #/Y9}
} \aSz2lxEHn
public void run(){ ZCiY,;c
long now = System.currentTimeMillis(); oK Kz 4
if ((now - lastExecuteTime) > executeSep) { Pern*x9$
//System.out.print("lastExecuteTime:"+lastExecuteTime); {sc[RRN~C
//System.out.print(" now:"+now+"\n"); a1x7~)z>zi
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); K;kM_%9u
lastExecuteTime=now; T)\NkM&
executeUpdate(); -}<g-*m"q
} 9&jPp4qG
else{ LdWc
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); >BiRk%x
} "n- pl
} 70iH0j)
} >!BFt$sd
//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 ( tn<
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类写好了,下面是在JSP中如下调用。 J|j;g!fK
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<% xdF guV8
CountBean cb=new CountBean(); |`]oc,1h@
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); O~'FR[J
CountCache.add(cb); {\We72!
out.print(CountCache.list.size()+"<br>"); _X%Dw
CountControl c=new CountControl(); yq*JdTF
c.run(); fi=?n{e'
out.print(CountCache.list.size()+"<br>"); 9) ea.Gu
%>