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: ->{d`-}m'
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CountBean.java &}6KPA;
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/* }YhtUWz].
* CountData.java DPn=n9n2
* ?DV5y|}pj
* Created on 2007年1月1日, 下午4:44 >ezi3Zx^
* 5II(mSg8
* To change this template, choose Tools | Options and locate the template under Ard]147
* the Source Creation and Management node. Right-click the template and choose =}!Mf'
* Open. You can then make changes to the template in the Source Editor. #uCB)n&.
*/ [/M^[p
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package com.tot.count; *LC+ PZV@
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/** Mj=$y?d ]
* 24c ek
* @author }R4c
*/ cE'L% Z
public class CountBean { y3u+_KY-
private String countType; E.bi05l
int countId; sW#JjtK
/** Creates a new instance of CountData */ wN-i?Ek0;
public CountBean() {} 1j-te-}"c
public void setCountType(String countTypes){ ^D^JzEy'?C
this.countType=countTypes; revF;l6->C
} OFkNl}D
public void setCountId(int countIds){ YcX/{L[9o
this.countId=countIds; Ter:sge7
} zvc`3
public String getCountType(){ 'J)2g"T@
return countType; =:,xxqy
} e-hjC6Q U
public int getCountId(){ ![6EUMx
return countId; q=Zr>I;(Ks
} +k<w!B*
} x`RTp:#
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CountCache.java ]q5`YB%_
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/* <bck~E
* CountCache.java fU3`v\X
* 7}O.wUKw%
* Created on 2007年1月1日, 下午5:01 BKa-
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* &)F*@C-
* To change this template, choose Tools | Options and locate the template under ikB Yd
}5
* the Source Creation and Management node. Right-click the template and choose G$zL)R8GE|
* Open. You can then make changes to the template in the Source Editor. f$HH:^#
*/ 2I1uX&g
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package com.tot.count; P>Euq'ajX
import java.util.*; S"m cUU}}
/** `fXyWrz-k
* c?2MBtnu
* @author J<gJc*Q
*/ h&3YGCl
public class CountCache { qGmNz}4D5
public static LinkedList list=new LinkedList(); X .F^$
/** Creates a new instance of CountCache */ ''OfS D_g
public CountCache() {} lS^(&<{
public static void add(CountBean cb){ =,!\~`^
if(cb!=null){ "<+ih0Ma
list.add(cb); T=a=B(
} d@0Kr5_
} H1"q
} DciwQcG
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CountControl.java {%v-(
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/* Y<"7x#AB!
* CountThread.java x]mxD|?f
* vP@v.6gS,
* Created on 2007年1月1日, 下午4:57 %%ae^*[!n
* ^I
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* To change this template, choose Tools | Options and locate the template under }U w&Ny
* the Source Creation and Management node. Right-click the template and choose wu9=N
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* Open. You can then make changes to the template in the Source Editor. o'<^LYSnB
*/ bOp54WI-g
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package com.tot.count; R=Ws#'
import tot.db.DBUtils; Il@Y|hK
import java.sql.*; { x0 t
/** H=g.34
* L%}zVCg
* @author 8;Fn7k_Uf
*/ e}VBRvr
public class CountControl{ 39F
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private static long lastExecuteTime=0;//上次更新时间 ^taBG3P
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 OU4pjiLx
/** Creates a new instance of CountThread */ ,vqr<H9e
public CountControl() {} |]Z:&[D]i
public synchronized void executeUpdate(){ e
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Connection conn=null; YKbCdLQ
PreparedStatement ps=null; j/T>2|dA&
try{ (}r|yE
conn = DBUtils.getConnection(); Ioy
conn.setAutoCommit(false); 4Tc&IwR
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); L\{IljA
for(int i=0;i<CountCache.list.size();i++){ Lj\/Ji_
CountBean cb=(CountBean)CountCache.list.getFirst(); ik|-L8
CountCache.list.removeFirst(); g[>\4B9t
ps.setInt(1, cb.getCountId()); $N']TN
ps.executeUpdate();⑴ _qqr5NU
//ps.addBatch();⑵ l JP1XzN_
} 8 #X5K
//int [] counts = ps.executeBatch();⑶ yL^UE=#C_
conn.commit(); +`M!D }!
}catch(Exception e){ @pI5lh
e.printStackTrace(); f=!PllxL:
} finally{ {y] mk?j
try{ '$As<LOEd/
if(ps!=null) { YJS{i
ps.clearParameters(); oBq 49u1
ps.close(); 1pv}]&X
ps=null; qrvsjYi*w
} 49Df?sx
}catch(SQLException e){} *tOG*hwdT
DBUtils.closeConnection(conn); GT hL/M
} UmnE@H"t$\
} e6X[vc|Y}
public long getLast(){ 6J~12TU,
return lastExecuteTime; X1[CX&Am
} O<)y-nx;X
public void run(){ 22<0DhJ
long now = System.currentTimeMillis(); ki0V8]HP
if ((now - lastExecuteTime) > executeSep) { MF60-VE
//System.out.print("lastExecuteTime:"+lastExecuteTime); &AuF]VT
//System.out.print(" now:"+now+"\n"); 0U/K7sZ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Dlo xrdOY&
lastExecuteTime=now; DcIvhB p
executeUpdate(); cr?7O;,
} to8X=80-3
else{ &bqT/H18
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); }7G8|54t
} FG3UZVUg9
} f\;65k_jq
} f"7M^1)h2%
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Z34Wbun4
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类写好了,下面是在JSP中如下调用。 /MB{Pmk$R
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<% 6~#Ih)K
CountBean cb=new CountBean(); HIGq%m=-x
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ;U:
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CountCache.add(cb); 3'c\;1lhT
out.print(CountCache.list.size()+"<br>"); M@P1, Y
CountControl c=new CountControl(); gx03xPeu
c.run(); {:c]|^w6
out.print(CountCache.list.size()+"<br>"); k+V6,V)my
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