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: _)LXD,LA
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CountBean.java VJA/d2Oys
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/* D\ZH1C!d
* CountData.java NH5sV.vvc
* t?^!OJ:L
* Created on 2007年1月1日, 下午4:44 t~}c"|<t
* WJ8osWdLu
* To change this template, choose Tools | Options and locate the template under D0
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* the Source Creation and Management node. Right-click the template and choose Qru&lAYc<
* Open. You can then make changes to the template in the Source Editor. 3XUVUd~
*/ Xsn M}
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package com.tot.count; c#u_%*
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/** _lT'nFe=Q
* X%99@ qv
* @author "IpbR
*/ d/+s-g p
public class CountBean { 2_bEo
private String countType; JSq3)o9?/
int countId; LO%e1y
/** Creates a new instance of CountData */ FwKY;^`!d
public CountBean() {} S,|ZCl>+
public void setCountType(String countTypes){ J7dHD(R8
this.countType=countTypes; 8t< X
} S+Ia2O)BA
public void setCountId(int countIds){ ^v5]Aq~X
this.countId=countIds; ON{a'H
} $B9?>a|{A
public String getCountType(){ usK P9[T$
return countType; DIP%*b#l$\
} ,QA=)~;D
public int getCountId(){ KDf#e3
return countId; 9 M?UPE
} 5D-as9k*
} q$H@W.f
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CountCache.java :%28*fl
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/* lpB:lRM
* CountCache.java GaJE(N
* f;+.j/ +
* Created on 2007年1月1日, 下午5:01 ]4')H;'y
* @az<D7j2
* To change this template, choose Tools | Options and locate the template under $6ucz'
* the Source Creation and Management node. Right-click the template and choose oFt_ yU-
* Open. You can then make changes to the template in the Source Editor. 0.PG]K6
*/ \Lb wfd=
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package com.tot.count; ;K4=fHl
import java.util.*; l ~xXy<
/** a3:45[SO4e
* D;48VK/Q
* @author Zy)iNNtn
*/ T1?9E{bC8A
public class CountCache { xIb{*)BUwc
public static LinkedList list=new LinkedList(); xVI"sBUu
/** Creates a new instance of CountCache */ BTOl`U
public CountCache() {} >pol'=
public static void add(CountBean cb){ cN2Pl%7
if(cb!=null){ *Br
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list.add(cb); uHZjpMoM
} ~U ]%>Zf
} (Xzq(QV
} Gw6Odj
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CountControl.java SN}3
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/* wT3D9N.
* CountThread.java 1Qjc*+JzO.
* K0@bh/i/^
* Created on 2007年1月1日, 下午4:57 S@
y! 0,
* ht+wi5b
* To change this template, choose Tools | Options and locate the template under @QYCoEU8J
* the Source Creation and Management node. Right-click the template and choose 23+JuXC6>
* Open. You can then make changes to the template in the Source Editor. ':
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*/ RZ9_*Lq7+
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package com.tot.count; 9Ns%<FRO@
import tot.db.DBUtils; ;_ 1Rk&o!
import java.sql.*; |<1A<fU8a
/** U(~Nmo'
* *y+K{ fM1
* @author /L]@k`.q@
*/ .345%j
public class CountControl{ KAT"!b
private static long lastExecuteTime=0;//上次更新时间 =:TQ_>$Nc2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 <h~uGBS"
/** Creates a new instance of CountThread */ Q/HEWk
public CountControl() {} Fy>g*3
public synchronized void executeUpdate(){ E3x<o<v
Connection conn=null; nkN2Bqt$
PreparedStatement ps=null; C.}ho.}
r
try{ Un+- T
conn = DBUtils.getConnection(); zQGj,EAM}
conn.setAutoCommit(false); qM>Dt
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); AXo)(\
for(int i=0;i<CountCache.list.size();i++){ @P=n{-pIW
CountBean cb=(CountBean)CountCache.list.getFirst(); 6@d/k.3p
CountCache.list.removeFirst(); Y'}c$*OkI
ps.setInt(1, cb.getCountId()); xo-{N[r
ps.executeUpdate();⑴ ]N1,"W}
//ps.addBatch();⑵ hbx+*KM
} B>"-8#B[4
//int [] counts = ps.executeBatch();⑶ :^x,>(a
conn.commit(); K)\D,5X^
}catch(Exception e){ f?@M"p@T
e.printStackTrace(); ?f5||^7
} finally{ .Rb4zLYL*w
try{ '&]6(+I>
if(ps!=null) { d%!yFix;<
ps.clearParameters(); UU#$Kt*frR
ps.close(); }$@K
ps=null; %yR80mn8
} @ L/i
}catch(SQLException e){} -H5-6w$
DBUtils.closeConnection(conn); 3m~3l d
} *JWPt(bnI
} cvpZF5mL]U
public long getLast(){ (5 RZLRn
return lastExecuteTime; &k(tDP
} |>Pv2
public void run(){ IJ{VCzi
long now = System.currentTimeMillis(); *@YQr]~
;
if ((now - lastExecuteTime) > executeSep) { 6iEA._y
//System.out.print("lastExecuteTime:"+lastExecuteTime); {PL,3EBG
//System.out.print(" now:"+now+"\n");
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Kc3/*eu;
lastExecuteTime=now; ;~}!P7z
executeUpdate(); k$,y1hH;f8
} `y1,VY
else{ V* ,u;*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); b#S-u }1PE
} YIl,8!
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} &';@CeK
} Ds8x9v)^
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 8nSw7:z
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类写好了,下面是在JSP中如下调用。 PJh97%7
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<% *m6*sIR
CountBean cb=new CountBean(); ?Xp+5{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); c,*a|@
CountCache.add(cb); s6oIj$
out.print(CountCache.list.size()+"<br>"); {Q0DHNP(G
CountControl c=new CountControl();
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c.run(); gdqED}v
out.print(CountCache.list.size()+"<br>"); t.7_7`bin~
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