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: QMIXz[9w
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CountBean.java (w.B_9#
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/* g%Z;rDfi
* CountData.java <ANKoPNie
* #&2mu
* Created on 2007年1月1日, 下午4:44 DeUDZL%/
* T<OLfuV
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose V{n pK(
* Open. You can then make changes to the template in the Source Editor. ?$
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*/ NM4 n
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package com.tot.count; u*M*WpY
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/** qG;WX n
* -x7L8Wj
* @author e1H.2n{y^
*/ K= 69z
public class CountBean { Po2YDj`
private String countType; !} 1p:@
int countId; P=h2Z,2
/** Creates a new instance of CountData */ = *sP,
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public CountBean() {} a7+BAma<
public void setCountType(String countTypes){ <Z vG&
this.countType=countTypes; D@2Tx
} xzy9~))o
public void setCountId(int countIds){ kxKBI{L
this.countId=countIds; cv^^NgQ
} `: 8&m
public String getCountType(){ lU@ni(69d
return countType; (Yx rZ_F'b
} p~r +2(J
public int getCountId(){ Y4 i-Pp?
return countId; 4[6A~iC_
} '\9A78NV{;
} #i~.wQ$1
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CountCache.java TPkm~>zD.
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/* nI6`/
* CountCache.java ^,?]]=mE
* XpM#0hm
* Created on 2007年1月1日, 下午5:01 `+<5QtD
* pdE=9l'
* To change this template, choose Tools | Options and locate the template under 7_JK2
* the Source Creation and Management node. Right-click the template and choose )q#b^( v
* Open. You can then make changes to the template in the Source Editor. %1#5
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*/ W
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package com.tot.count; K$rH{dUM
import java.util.*; TfJB;
/** GE"#.J4z
* E;h#3
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* @author Q.!8q3`
*/ ^*iZN
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public class CountCache { 1{DHlyA6g
public static LinkedList list=new LinkedList(); )9Jt550(
/** Creates a new instance of CountCache */ aeSXHd?+(
public CountCache() {} 4Jw0m#UN1
public static void add(CountBean cb){ t.]oLG22r
if(cb!=null){ 0BD3~Lv
list.add(cb); G $?VYC8;
} d(h`bOjI
} JL]6o8x
} *s_)E2
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CountControl.java .>&kAf.
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/* [/#;u*n
* CountThread.java )(,+o
* Pj+XKDV]T
* Created on 2007年1月1日, 下午4:57 )'nGuL-w!i
* lGs fs(
* To change this template, choose Tools | Options and locate the template under %[RLc[pB
* the Source Creation and Management node. Right-click the template and choose pTcm2-J
* Open. You can then make changes to the template in the Source Editor. bGDV9su
*/ x3)qK6,\
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package com.tot.count; nE,"3X"
import tot.db.DBUtils; _w(SHWh2
import java.sql.*; (zUERw\aX
/** c,e
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* _pW\F(+8
* @author ^f>+5G
*/ 514;!Q4K
public class CountControl{ aN.Phn:
private static long lastExecuteTime=0;//上次更新时间 M,6m*
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 (/c9v8Pr(7
/** Creates a new instance of CountThread */ 3q<\
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public CountControl() {} sHKT]^7
public synchronized void executeUpdate(){ ca-|G'q
Connection conn=null; 1J^{h5?lU
PreparedStatement ps=null; yay{lP}b"
try{ RzNv|
conn = DBUtils.getConnection(); {V8v
conn.setAutoCommit(false); LR}b^QU7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~`T3 i
for(int i=0;i<CountCache.list.size();i++){ \U,.!'+
CountBean cb=(CountBean)CountCache.list.getFirst(); Xa+ u>1"2"
CountCache.list.removeFirst(); Ao 1*a%-.
ps.setInt(1, cb.getCountId()); DaaLRMQ=
ps.executeUpdate();⑴ ]Y:|%rvVH
//ps.addBatch();⑵ /)6<`S(
} 3%'$AM}+s
//int [] counts = ps.executeBatch();⑶ C2FewsRz
conn.commit(); 8L.Y0_x
}catch(Exception e){ ]M>mwnt+
e.printStackTrace(); N3i}>Q)B
} finally{ 1[/X$DyaK
try{ H$WuT;cTE
if(ps!=null) { 7 zK%CJ
ps.clearParameters(); Fn$EP:>
ps.close(); +.5 /4?
ps=null; T[L
} HBeOK
}catch(SQLException e){} D.4=4"qMi
DBUtils.closeConnection(conn); #~ UG9@a
} p-r}zc9@
} 'ym/@h7h
public long getLast(){ &`GQS|
return lastExecuteTime; StA5h+[m
} $
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public void run(){ JT, 8/o
long now = System.currentTimeMillis(); \Ua"gS2L
if ((now - lastExecuteTime) > executeSep) { 4 mPCAA7
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^HQg$}=
//System.out.print(" now:"+now+"\n"); rl[&s\[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }`M[%]MNc
lastExecuteTime=now; 9psD"=/"
executeUpdate(); ! ai, \
} ;)~loa1\
else{ m^% [
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0k0y'1SL
} G)M9to
} MW6d-
} S2h?Q$e3
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释
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类写好了,下面是在JSP中如下调用。 NAlYfbp
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<% a3sXl+$D@
CountBean cb=new CountBean(); a>G|t5w
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); s-~Tf|
CountCache.add(cb); -!k"*P
out.print(CountCache.list.size()+"<br>"); vn9_tL&
CountControl c=new CountControl(); he;&KzEu
c.run(); MkF:1-=L
out.print(CountCache.list.size()+"<br>"); YFL9Q<
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