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: 3)Y:c2
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CountBean.java Fev3CV$
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/* Ks(U]G"V
* CountData.java U5"Oh I
* '9@R=#nd
* Created on 2007年1月1日, 下午4:44 :8rCCop
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* `'WLGQG
* To change this template, choose Tools | Options and locate the template under Kf#!IY][
* the Source Creation and Management node. Right-click the template and choose 5eA]7$ic
* Open. You can then make changes to the template in the Source Editor. m12B:f
*/ wjOAgOC
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package com.tot.count; R:?vY!
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/** |m- `,
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* @author VWt'Kx"
*/ "M^W:4_
public class CountBean { G`"Cqs<
private String countType; <>_WdAOuD
int countId; )AXH^&
/** Creates a new instance of CountData */ }3w b*,Sbz
public CountBean() {} ~b0qrjF;O
public void setCountType(String countTypes){ WmUW
i{
this.countType=countTypes; A#&qoZ(C
} (p=GR#
public void setCountId(int countIds){ R"`{E,yj
this.countId=countIds; :* b4/qpYv
} =fK'Ep[
public String getCountType(){ om?CFl
return countType; ~-wJ#E3g
} X:&p9_O@
public int getCountId(){ 0z7mre^Q
return countId; 7"p s#)O
} ]xEE7H]\h
} RI3{>|*
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CountCache.java shIi,!bZ
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/* F
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* CountCache.java a<TL&
* )Cvzj<Q0
* Created on 2007年1月1日, 下午5:01 X@U1Ri
* :<k|u!b}y
* To change this template, choose Tools | Options and locate the template under c0q)
* the Source Creation and Management node. Right-click the template and choose 4!vUksM
* Open. You can then make changes to the template in the Source Editor. O7'3}P;
*/ 2EwWV0BS
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package com.tot.count; Cf[F`pFM
import java.util.*; Gj`Y2X2r
/** cE5Zxcn
* Mk/!,N<h#
* @author h./vTNMc
*/ )=nPM`Jn.
public class CountCache { !r
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public static LinkedList list=new LinkedList(); )+4}Ix/q
/** Creates a new instance of CountCache */ O) %kl
public CountCache() {} [.xk
public static void add(CountBean cb){ Pl&`&N;
if(cb!=null){ =v$s+`cP
list.add(cb); YzW7;U
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} "UGj4^1f
} =^y{@[p`(
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CountControl.java ugCS &
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/* Ny,A#-?
* CountThread.java )-KE 4/G
* m_02"'
* Created on 2007年1月1日, 下午4:57 \}QuNwc
* 2$zq (
* To change this template, choose Tools | Options and locate the template under ([dL:Fb
* the Source Creation and Management node. Right-click the template and choose afiK!0col2
* Open. You can then make changes to the template in the Source Editor. vLFaZ^(
*/ vq:OH
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package com.tot.count; J&ECm+2
import tot.db.DBUtils; [2 w<F[
import java.sql.*; :#:O(K1PW
/** pUMB)(<k
* w+q;dc8
* @author 9'#.>Q>0=j
*/ e$+f~~K
public class CountControl{ a05:iFoJ
private static long lastExecuteTime=0;//上次更新时间 *R\/#Y|
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 xT?} wF
/** Creates a new instance of CountThread */ <C"N X
public CountControl() {} ,x"yZ
public synchronized void executeUpdate(){ QC5f:BwM
Connection conn=null; ->2wrOH|H
PreparedStatement ps=null; vs])%l%t
try{ x$?7)F&z
conn = DBUtils.getConnection(); |k
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conn.setAutoCommit(false); @W\4UX3dK
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ddq 1NW
for(int i=0;i<CountCache.list.size();i++){ 1;:t~Y
CountBean cb=(CountBean)CountCache.list.getFirst(); @23RjoK
CountCache.list.removeFirst(); gLSG:7m@
ps.setInt(1, cb.getCountId()); `TD%M`a
ps.executeUpdate();⑴ ?I2k6%a
//ps.addBatch();⑵ fZV8o$V
} 7|M $W(P
//int [] counts = ps.executeBatch();⑶ Z:lB:U'o
conn.commit(); AK
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}catch(Exception e){ !E{GcK
e.printStackTrace(); |Iok(0V
} finally{ {I9N6BQ&
try{ 7hF,gl5
if(ps!=null) { akvwApn5
ps.clearParameters(); E7NbPNd
ps.close(); g t^]32$
ps=null; 2VV[*QI
} ,KhMzE8_a
}catch(SQLException e){} B==a
DBUtils.closeConnection(conn); nze1]3`
} g"!#]LLe
} =SK+\j$
public long getLast(){ w{e3U7;
return lastExecuteTime; /pIb@:Y1?
} <qq'h
public void run(){ UC+7-y,
long now = System.currentTimeMillis(); le^_6|ek
if ((now - lastExecuteTime) > executeSep) { x<*IF,o
//System.out.print("lastExecuteTime:"+lastExecuteTime); aEEz4,x_
//System.out.print(" now:"+now+"\n"); aFr!PQp4{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); k99gjL`
lastExecuteTime=now; b1+hr(kMRM
executeUpdate(); -_EY$?4
} )`s;~_ZZ
else{ >^H'ZYzw
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Cwsoz
} Ck3QrfM
} =|gJb|?w
} 3Zaq#uA
//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 N0K>lL=
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类写好了,下面是在JSP中如下调用。 VM!-I8t
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<% BA1MGh
CountBean cb=new CountBean(); t(j_eq}J
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); l~fh_IV1
CountCache.add(cb); xgtJl}L
out.print(CountCache.list.size()+"<br>"); B%eDBu
")
CountControl c=new CountControl(); cVB|sYdf
c.run(); k_K,J6_)
out.print(CountCache.list.size()+"<br>"); ?@lx
%>