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: 78b9Sdi&
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CountBean.java e8]mdU{)
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/* &P8Q|A-u
* CountData.java x2f_>tu2
* FUPJ&7+B
* Created on 2007年1月1日, 下午4:44 T5U(B3j_
* H
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* To change this template, choose Tools | Options and locate the template under }% |GV
* the Source Creation and Management node. Right-click the template and choose R?%|RCht1
* Open. You can then make changes to the template in the Source Editor. inGH'nl_
*/ P#Ikj&l
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package com.tot.count; \@n/L{}(@
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/** bL7mlh
* !C0=
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* @author zjJyc?
*/ WUi7~Ei}
public class CountBean { %}&9[#
private String countType; L'h'm{i
int countId; {la^useg[
/** Creates a new instance of CountData */ R?\8SdJ
public CountBean() {} ?Z7C0u#wd
public void setCountType(String countTypes){ 8c$IsvJg
this.countType=countTypes; &l|B>{4v
} r>q`# ~
public void setCountId(int countIds){ 8i"{GGVC
this.countId=countIds; {gi"ktgk
} 1Kebl
public String getCountType(){ veE8
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return countType; 7,LT4wYH
} Z#W`0G>'
public int getCountId(){ L,X6L @Q
return countId; 9k"nx ,"
} #wm)e)2@
} bmddh2
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CountCache.java j({L6</x
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/* "ChBcxvxb:
* CountCache.java z?YGE iR/}
* eZJOI1wNp
* Created on 2007年1月1日, 下午5:01 i|d41u;@
* y.eBFf
* To change this template, choose Tools | Options and locate the template under ;NPb
* the Source Creation and Management node. Right-click the template and choose %r,2ZLZ
* Open. You can then make changes to the template in the Source Editor. hQ8{
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*/ >\p}UPx
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package com.tot.count; =O_[9kuJ
import java.util.*; 02S(9^=
/** ta4<d)nB
* <*5D0q#~"
* @author 3 \WdA$Wx
*/ kI;^V
public class CountCache { WK^qYfq|
public static LinkedList list=new LinkedList(); 1!NaOfP;@
/** Creates a new instance of CountCache */ dX3>j{_
public CountCache() {} %E!0,y,:
public static void add(CountBean cb){ fu&]t8MJC
if(cb!=null){ 5Np. &
list.add(cb); XZT( :(
} Wl2>U(lj
} [E /3&3
} Mo<p+*8u:
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CountControl.java nz&JG~Qfm
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/* e
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* CountThread.java +%~g$#tlJo
* t-Fl"@s
* Created on 2007年1月1日, 下午4:57 wIiT
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* V)Xcn'h
* To change this template, choose Tools | Options and locate the template under ^b.J z}
* the Source Creation and Management node. Right-click the template and choose 8ksDXf`.
* Open. You can then make changes to the template in the Source Editor. V!=]a^]:
*/ eK@Y] !lz
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package com.tot.count; 8+ W^t I
import tot.db.DBUtils; Zn!SHj
import java.sql.*; #WG(V%f]
/** `'QPe42
* t8[:}[Jx
* @author [6tQv<}^
*/ @'y"D
public class CountControl{ $7*Ml)H!9
private static long lastExecuteTime=0;//上次更新时间 vtT:c.~d
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 &Gt9a-ne
/** Creates a new instance of CountThread */ +Snjb0
public CountControl() {} :4Vt
public synchronized void executeUpdate(){ g<-cHF
Connection conn=null; }A;Xd/,'r
PreparedStatement ps=null; 334*nQ
try{ wDG4rN9x
conn = DBUtils.getConnection(); KKzvoc?Bt
conn.setAutoCommit(false); RinRQd
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); btE+.V
for(int i=0;i<CountCache.list.size();i++){ / u{r5`4
CountBean cb=(CountBean)CountCache.list.getFirst(); M>#{~zr
CountCache.list.removeFirst(); >j?uI6Uw
ps.setInt(1, cb.getCountId()); G#C)]4[n
ps.executeUpdate();⑴ hU{%x#8}lK
//ps.addBatch();⑵ EKf4f^<
} k4P.}SJ?
//int [] counts = ps.executeBatch();⑶ 57}q'84
conn.commit(); Sq'z<}o
}catch(Exception e){ P;/T`R=Vr"
e.printStackTrace(); '$VR_N\
} finally{ hg~fFj3ST
try{ ]=3O,\
if(ps!=null) { J @fE")
ps.clearParameters(); 4SrK]+|
ps.close(); ^s*} 0
ps=null; VGq]id{*$
} {1+H\(v
}catch(SQLException e){} FRW.
DBUtils.closeConnection(conn); 8FITcK^
} A0ToX) |C
} !Z ZA I_N
public long getLast(){ SOL=3hfb^
return lastExecuteTime; >vU
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} 1DP)6{x
public void run(){ yN.D(ZwF:
long now = System.currentTimeMillis(); GdU
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if ((now - lastExecuteTime) > executeSep) { %ab79RS]C
//System.out.print("lastExecuteTime:"+lastExecuteTime); jo*9QO
//System.out.print(" now:"+now+"\n"); -G 'lyH
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); e{,/
lastExecuteTime=now; mI%/k7:sf
executeUpdate(); NsHveOK1.
} QFYy$T+W
else{ a6d KQ3D
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); I'C,'
} :Eyv= =
} 5,Y2Lzr
} K;PpS*!
//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=A9ax
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类写好了,下面是在JSP中如下调用。 hz%IxI9
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<%
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CountBean cb=new CountBean(); ;GSJnV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); *&]l
CountCache.add(cb); 2LU'C,o?
out.print(CountCache.list.size()+"<br>"); P>-,6a>
CountControl c=new CountControl(); ?
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c.run(); =.a ]?&Yyh
out.print(CountCache.list.size()+"<br>"); M6sDtL9l
%>