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: '|l1-yD_
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CountBean.java q%GlS=o"
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/* TW?A/GoXI
* CountData.java Ny)!uqul*
* FQCz_z
* Created on 2007年1月1日, 下午4:44 '0>w_ge4
* 2q.J1:lW
* To change this template, choose Tools | Options and locate the template under &8uq5uKg
* the Source Creation and Management node. Right-click the template and choose *J] }bX
* Open. You can then make changes to the template in the Source Editor. '\.fG\xD
*/ (
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package com.tot.count;
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/** 0')O4IHH
* 8DP] C9
* @author =7uxzg/%Tj
*/ w#M66=je_
public class CountBean { E%6}p++
private String countType; 7nAB^~)6l
int countId; Z-,'M tD
/** Creates a new instance of CountData */ k~ZE4^dM
public CountBean() {} 9.qjEe
public void setCountType(String countTypes){ zQQ=8#]
this.countType=countTypes; p$
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} ACcxQK}
public void setCountId(int countIds){ V/}g'_E
this.countId=countIds; z<c@<M=Q*
} fB3W} dr
public String getCountType(){ !4B($]t
return countType; !B &%!06
} B'Ll\<mq@
public int getCountId(){ +
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return countId; }?jL;CCe
} @NS=
} kG>d^K
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CountCache.java O_jf)N\pi
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/* 4 u!)QG
* CountCache.java c~a:i=y67
* !yQ# E2/A
* Created on 2007年1月1日, 下午5:01 0"_FQv
* *u4h+P
* To change this template, choose Tools | Options and locate the template under _Hn-bp[?>
* the Source Creation and Management node. Right-click the template and choose nT.2HQ((Xg
* Open. You can then make changes to the template in the Source Editor. $($26g
*/ pIy+3&\e;
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package com.tot.count; D> |R.{
import java.util.*; ' s6SKjZS
/** 7C%z0/
* 4iiW{rh4
* @author Z;6v`;[
*/ prx)Cfv
public class CountCache { Z2,[-8,Kx
public static LinkedList list=new LinkedList(); [80L|?, *
/** Creates a new instance of CountCache */ P<@V
public CountCache() {} 8e 9ZgC|
public static void add(CountBean cb){ t_PAXj
if(cb!=null){ yJJNr]oq
list.add(cb); CfoT$g
}
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} `$*cW1
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CountControl.java ySLa4DQf
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/* %\5d?;
* CountThread.java kCO`JAH#
* !vB8Pk"
* Created on 2007年1月1日, 下午4:57 n.{Ud\|
* mBC?Pg
* To change this template, choose Tools | Options and locate the template under SW
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* the Source Creation and Management node. Right-click the template and choose G G]4g)O5
* Open. You can then make changes to the template in the Source Editor. )!:}R}q
*/ 7n,*3;I
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package com.tot.count; #3l&N4/
import tot.db.DBUtils; j~d<n_
import java.sql.*; jU~
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/** y3 vDKZ
* Ydw04WEJ
* @author _<`j?$P
*/ t7"vAjZU
public class CountControl{ Uk=-A
@q
private static long lastExecuteTime=0;//上次更新时间 f,'gQ5\ X3
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 brk>oM;t
/** Creates a new instance of CountThread */ XANPI|
public CountControl() {} 2nL[P#r
public synchronized void executeUpdate(){ .]_
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Connection conn=null;
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PreparedStatement ps=null; 0(2r"Hi
try{ VfK8')IXk
conn = DBUtils.getConnection(); DeTx7 i0
conn.setAutoCommit(false); xWv@PqXD
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); WQ(*A
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for(int i=0;i<CountCache.list.size();i++){ dvWQ?1l_
CountBean cb=(CountBean)CountCache.list.getFirst(); T(UPWsj
CountCache.list.removeFirst(); &\Es\qVSf
ps.setInt(1, cb.getCountId()); &R\t<X9 n
ps.executeUpdate();⑴ a9h K8e
//ps.addBatch();⑵ Sl,\<a
} b'1n1L
//int [] counts = ps.executeBatch();⑶ sOegR5?;
conn.commit(); h JVy-]
}catch(Exception e){ fO+$`r>9
e.printStackTrace(); umt*;U=
} finally{ 2WK]I1_
try{ i$GL]0
if(ps!=null) { 8ug\GlZc
ps.clearParameters(); E>t5/^c)*w
ps.close(); Q Q3a&
ps=null; g]sc)4
} _sEkKh8x
}catch(SQLException e){} >l & N
DBUtils.closeConnection(conn); ?U\@?@
} AATiI+\S
} ,i>{yrsOh
public long getLast(){ @+OX1-dd/w
return lastExecuteTime; noali96J
} O_yk<
public void run(){ z+RA
long now = System.currentTimeMillis(); llbf(!
if ((now - lastExecuteTime) > executeSep) { F|,_k%QP
//System.out.print("lastExecuteTime:"+lastExecuteTime); v1s.j2T
//System.out.print(" now:"+now+"\n"); n]?KDID;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); A2fc_A/a
lastExecuteTime=now; v{/z`J!JR
executeUpdate(); A4lW8&rHI
} C5q
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else{ o5NV4=
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); F}/tV7m
} =Oo=&vA.oc
} :qfP>Ok
} UMcQqV+vT
//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 8F?6Aq1B
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类写好了,下面是在JSP中如下调用。 l[Hgh,
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<% T d E.e(
CountBean cb=new CountBean(); gj(|#n5C
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Fx6c*KNX3
CountCache.add(cb); ?AMn>v
out.print(CountCache.list.size()+"<br>"); ?X'm>R. @
CountControl c=new CountControl(); 2pKkg>/S
c.run(); G?p !*7N
out.print(CountCache.list.size()+"<br>"); p_^Jr*Mv
%>