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: n8<?<-2
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CountBean.java oL@ -<;zKO
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/* w-pgtO|Us
* CountData.java V'j+)!w5
* 6XWNJb
* Created on 2007年1月1日, 下午4:44 -p_5T*R
* ^7spXfSAd
* To change this template, choose Tools | Options and locate the template under 4tZ *%!I'
* the Source Creation and Management node. Right-click the template and choose kP%hgZ
* Open. You can then make changes to the template in the Source Editor. mp8GHV
*/ />S^`KSTM
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package com.tot.count; gQ{ #C'
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/** tdH[e0x B
* {h+8^
* @author =%7drBo D
*/ tr<fii3<
public class CountBean { |ky40[C
private String countType; `MSig)V
int countId; jjV'`Vy)
/** Creates a new instance of CountData */ t`H1]`c?
public CountBean() {} n>ui'}L
public void setCountType(String countTypes){ $K^l=X
this.countType=countTypes; " !EnQB=
} OZxJDg
public void setCountId(int countIds){ ,-e}Xw9
this.countId=countIds; [LnPV2@e
} Gw<D'b)!
public String getCountType(){ ;-Yvi,sS+
return countType; {}YA7M:L
} ,' |J
public int getCountId(){ <!sLfz?
return countId; Nbpn"*L,
} 44ty,M3
} r1r$y2v~
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CountCache.java Km(i}:6"
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/* xQFY/Z
* CountCache.java { ^dq7!
* U4!KO;Jc
* Created on 2007年1月1日, 下午5:01 xfb .Z(
* G+<XYkz*
* To change this template, choose Tools | Options and locate the template under 0*XsAz1,9
* the Source Creation and Management node. Right-click the template and choose "'z}oS
* Open. You can then make changes to the template in the Source Editor. Fe0M2%e;|
*/ *-9i<@|(U^
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package com.tot.count; F=Bdgg9s
import java.util.*; @Y/&qpo$#W
/** 2#.s{ Bv
* %P0
* @author 0&,D&y%
*/ hQ@k|3=Re
public class CountCache { 1cK'B<5">]
public static LinkedList list=new LinkedList(); XH?//.q
/** Creates a new instance of CountCache */ unFRfec{
public CountCache() {} ircF3P>a?
public static void add(CountBean cb){ a}%f+`z
if(cb!=null){ sq2:yt
list.add(cb); \\dUp>1=
} `7=$I~`
} AmF[#)90P
} vu+g65"
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CountControl.java &gp&i?%X9b
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/* "UTW(~D'
* CountThread.java Xq;|l?,O
* \|0z:R;X
* Created on 2007年1月1日, 下午4:57 yu'-'{%
* 4Im>2)
* To change this template, choose Tools | Options and locate the template under R&Lqaek&W
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. E]mm^i`|
*/ 9-pt}U
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package com.tot.count; <Z%=lwtX
import tot.db.DBUtils; ,\6Vb*G|E>
import java.sql.*; 712nD ?>
/** G`FYEmD
* (mIjG)4t
* @author p]mN)
*/ {mJ'
Lb0;
public class CountControl{ r:bJU1P1$s
private static long lastExecuteTime=0;//上次更新时间 qofAA!3z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Z5vdH5?!r
/** Creates a new instance of CountThread */ vxmX5.
public CountControl() {} -0^]:
public synchronized void executeUpdate(){ VM%g QOo<
Connection conn=null; v'i'I/
PreparedStatement ps=null; KZ%i&w#<
try{ i.t%a{gL
conn = DBUtils.getConnection(); OIPY,cj~
conn.setAutoCommit(false); e`n ZiM>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >/A]C$?3
for(int i=0;i<CountCache.list.size();i++){ C-y MWr
CountBean cb=(CountBean)CountCache.list.getFirst(); K83'`W^
CountCache.list.removeFirst(); D6L+mTN
ps.setInt(1, cb.getCountId()); aZb\uMePK
ps.executeUpdate();⑴ >:-e
//ps.addBatch();⑵ HEVjK$
} "Wj{+|f
//int [] counts = ps.executeBatch();⑶ G[>NP#P
conn.commit(); u+j\PWOtm
}catch(Exception e){ "9_$7.q<y
e.printStackTrace(); %6 *c40
} finally{ Z<;W*6J
try{ N
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if(ps!=null) { D&):2F^9.
ps.clearParameters(); ?h[HC"V/2
ps.close(); 8%K{l g"
ps=null; -Rpra0o.
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}
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}catch(SQLException e){} m#'eDO:
DBUtils.closeConnection(conn); q SNCBn '
} UQDAql
} MKfK9>a
public long getLast(){ f8;?WSGyD2
return lastExecuteTime; }<^mUG
} z,aMbgt
public void run(){ "SMJ:g",
long now = System.currentTimeMillis(); t$$YiO
if ((now - lastExecuteTime) > executeSep) { yP{ 52%|+
//System.out.print("lastExecuteTime:"+lastExecuteTime); !Aj}sh{
//System.out.print(" now:"+now+"\n"); >Hnm.?-AWl
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); *:n7B\.
lastExecuteTime=now; f]r*;YEc4
executeUpdate(); u
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} 67(s\
else{ ^.6yzlY
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); )g'J'_Sl
} V*@aE
} ;M.Q=#;E
} 0OM^,5%8
//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 M=raKb?F
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类写好了,下面是在JSP中如下调用。 \#,2#BmO"E
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<% 2p&$bft
CountBean cb=new CountBean(); @*y4uI6&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); [`@M!G.
CountCache.add(cb); W4o8]&A
out.print(CountCache.list.size()+"<br>"); r.eK;
CountControl c=new CountControl(); dcY(1p)
c.run(); RH FRN&RU$
out.print(CountCache.list.size()+"<br>"); H0s*Lb
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