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: SPKen}g
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CountBean.java Y ON@G5^
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/* lS P{9L6
* CountData.java d5<@WI:wz
* *UVjN_na5
* Created on 2007年1月1日, 下午4:44 7O5`&Z'-
* $4.mRS97g
* To change this template, choose Tools | Options and locate the template under EN@LB2
* the Source Creation and Management node. Right-click the template and choose :H[E
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* Open. You can then make changes to the template in the Source Editor. Ycb<'M*jE
*/ TSu^.K
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package com.tot.count; ]e+IaZ[Wo
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/** pJ7wd~wF*
* -eAo3
* @author L^PZ\OC
*/ K]dqK'
public class CountBean { PZ69aZ*Gs
private String countType; t!^FWr&
int countId; 3}O.B
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/** Creates a new instance of CountData */ g3{)AX[Uy
public CountBean() {} ;aYPv8s~,:
public void setCountType(String countTypes){ Wo5G23:xz
this.countType=countTypes; bu"Jb4_a>
} cn ,zUG!-h
public void setCountId(int countIds){ Db({k,P'Y
this.countId=countIds; jeb<qi>
} 2L.UEAt
public String getCountType(){ Q6?+# }
return countType; g#FqjE|mx
} uF5d
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public int getCountId(){ g-xbb&]
return countId; @t`|w.]ml
} G 8|[.n
} AG)N^yd
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CountCache.java "hz(A.THi
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/* q|2{W.P5qi
* CountCache.java ;}IF'ANA
* ~Av]LW
* Created on 2007年1月1日, 下午5:01 Y>!9P\Xe
* #m
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* To change this template, choose Tools | Options and locate the template under `9Ngax=_
* the Source Creation and Management node. Right-click the template and choose mm%w0dOb"
* Open. You can then make changes to the template in the Source Editor. G1B~?i2$ ?
*/ G~)jk+Qq
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package com.tot.count; *sf9(%j
import java.util.*; ] d| -r:4
/** :YjOv
* "Ks%!
* @author !Dkz6B*
*/ mh44
public class CountCache { d%9I*Qo0,
public static LinkedList list=new LinkedList(); n);2b\&
/** Creates a new instance of CountCache */ S|;a=K&hS
public CountCache() {} _5M!ec
public static void add(CountBean cb){ Ed#%F-1sX
if(cb!=null){ EH3jzE3N
list.add(cb); lsW.j#yE!
} `ZN@L<I6
} =Z/'|;Vd_x
} +YT/od1t7
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CountControl.java =pWpHbB.
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/* &{&lCBN
* CountThread.java aVuan&]*=
* ?>q=Nf^ Q.
* Created on 2007年1月1日, 下午4:57 =Cs$0aA
* pvy;L[c
* To change this template, choose Tools | Options and locate the template under PGT!HdX#{
* the Source Creation and Management node. Right-click the template and choose cv:nlq)
* Open. You can then make changes to the template in the Source Editor. 3~I<f^K4
*/ e^~t52]
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package com.tot.count; SfJ/(q
import tot.db.DBUtils; k;zbq
import java.sql.*; 2EE/xnwX
/** F)e*w:D
* "+nURdicO
* @author hv*n";V
*/ oZ6xHdPc4
public class CountControl{ F&lc8
private static long lastExecuteTime=0;//上次更新时间 Sc Gmft3A
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 9Lz)SYd
/** Creates a new instance of CountThread */ r_)-NOp
public CountControl() {} z('93vsO
public synchronized void executeUpdate(){ MBcOIy[&A
Connection conn=null; XP2=x_"y
PreparedStatement ps=null; a-!"m
try{ 1I3u~J3]/
conn = DBUtils.getConnection(); w])~m1yW
conn.setAutoCommit(false); >4M_jC.
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); N_pJE?
for(int i=0;i<CountCache.list.size();i++){ q(.%f3(
CountBean cb=(CountBean)CountCache.list.getFirst(); `H/HLCt
CountCache.list.removeFirst(); Cy6[p
ps.setInt(1, cb.getCountId()); |&n dQ(!l
ps.executeUpdate();⑴ AaTtYd
//ps.addBatch();⑵ O-T/H-J`
}
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//int [] counts = ps.executeBatch();⑶ =5Q;quKu^5
conn.commit(); (!X:[Ah*$
}catch(Exception e){ u6r-{[W}
e.printStackTrace(); fY%Sw7ql<
} finally{ NBMY1Xgj
try{ p6=#LwL'
if(ps!=null) { Arp4$h
ps.clearParameters(); @D"|Jq=6P
ps.close(); aE{b65'Dt
ps=null; "6KOql3
} ;SC|VcbyH
}catch(SQLException e){} DvOg|XUU0
DBUtils.closeConnection(conn); njUM>E,'
} {zF
} eA4*Be;9e
public long getLast(){ m(OBk;S~
return lastExecuteTime; ^ *
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} &u=FLp5
public void run(){ $ @1&G~x
long now = System.currentTimeMillis(); `SW`d<+L
if ((now - lastExecuteTime) > executeSep) { eHnC^W}|s
//System.out.print("lastExecuteTime:"+lastExecuteTime); 82/iVm1
//System.out.print(" now:"+now+"\n"); K=(&iq!VO
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); } |SVt`n
lastExecuteTime=now; STOE=TC>
executeUpdate(); 6@F Z,e
} 3"L$*toRA
else{ Be]o2N;J
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); GtGToI
} :cC`wX$
} {Z?!*Ow
} z0Zl'
//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 , JZ@qmQ,
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类写好了,下面是在JSP中如下调用。 :sA-$*&x
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<% }+=@Ci
CountBean cb=new CountBean(); xq~=T:>/A
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); &H+<uYV
CountCache.add(cb); 5~[Fh2+
out.print(CountCache.list.size()+"<br>"); 7L<oWAq
CountControl c=new CountControl(); @~N#)L^
c.run(); "t\9@nzdX
out.print(CountCache.list.size()+"<br>"); IS=)J( 0
%>