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: nUOi~cs
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CountBean.java pA6KiY&
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/* eHuJFM
* CountData.java M'PZ{6;
* WJ25fTsG
* Created on 2007年1月1日, 下午4:44 0RT 8N=B83
* du66a+@t
* To change this template, choose Tools | Options and locate the template under x}yl Rg`[
* the Source Creation and Management node. Right-click the template and choose IHni1
* Open. You can then make changes to the template in the Source Editor. A~2)ZdAN
*/ N)H "'#-
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package com.tot.count; ('tXv"fT
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/** 7C|!Wno[;
* (Jk&U8y
* @author [OW <<6
*/ /ce;-3+
public class CountBean { c Mgd
private String countType; #wI}93E
int countId; }IyF|[
/** Creates a new instance of CountData */ j#1G?MF
public CountBean() {} }OpUG
public void setCountType(String countTypes){ P.'.KZJ:WD
this.countType=countTypes; u^~7[OkE
} %.Ma_4o
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public void setCountId(int countIds){ rm8Ys61\=
this.countId=countIds; +;?mg(:
} >
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public String getCountType(){ q 84*5-
return countType; Aqmpo3P[+
} hMa; \ k
public int getCountId(){ Y~WdN<g
return countId; :&IHdf0+
} jYHn J}<
} Dfs*~H63
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CountCache.java
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/* X
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* CountCache.java {^WK#$]
* @>)VQf8s1
* Created on 2007年1月1日, 下午5:01 EtKq.<SJ
* +/~]fI
* To change this template, choose Tools | Options and locate the template under Xp:A;i9
* the Source Creation and Management node. Right-click the template and choose {]k#=a4
* Open. You can then make changes to the template in the Source Editor. }a7d(7
*/ (/e&m=~
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package com.tot.count; m+<&NDj.
import java.util.*; b/M/)o!C
/** /4G1,T_,
* Ti%MOYNCv
* @author D&G6^ME
*/ .a.HaBBV
public class CountCache { rH3U;K!
public static LinkedList list=new LinkedList(); P`biHs8O
/** Creates a new instance of CountCache */ *;fTiL
public CountCache() {} IT| h;NUG
public static void add(CountBean cb){ L4>14D\
if(cb!=null){ 9>)b6)J D
list.add(cb); ^kKLi
} )9YDNVo*-
} ZnEgU}g<2
} jHFjd'
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CountControl.java Lce,]z\_
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/* AY AU
* CountThread.java \@gV$+{9
* A{+/$7vek
* Created on 2007年1月1日, 下午4:57 UP-eKK'z
* kE&R;T`Gb%
* To change this template, choose Tools | Options and locate the template under ZISIW!
* the Source Creation and Management node. Right-click the template and choose T:za},-
* Open. You can then make changes to the template in the Source Editor. =Z\q``RBy
*/ 4uXGpsL
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package com.tot.count; OrkcY39"~a
import tot.db.DBUtils; C4mkt2Eb0a
import java.sql.*; gP%<<yl
/** x{1 v(n8+=
* )Te\6qM
* @author Tn7Mt7 h
*/ Y&6jFT_
public class CountControl{ {7:1F)Pj
private static long lastExecuteTime=0;//上次更新时间 7{#p'.nc5
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 b~gq8,Fatb
/** Creates a new instance of CountThread */ ynsYU(
public CountControl() {} j1_>>xB
public synchronized void executeUpdate(){ ,}t%7I
Connection conn=null; .I`>F/Sjr
PreparedStatement ps=null; O*u
try{ %J*1F
conn = DBUtils.getConnection(); 2*cNd}qr
conn.setAutoCommit(false); >ywl()4O
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); q[U pP`Z%
for(int i=0;i<CountCache.list.size();i++){ vMzL+D2)
CountBean cb=(CountBean)CountCache.list.getFirst(); )G2Bx+Z;L
CountCache.list.removeFirst(); C*YQ{Mz(f
ps.setInt(1, cb.getCountId()); T"g_a|7Tj
ps.executeUpdate();⑴ +6WjOcu
//ps.addBatch();⑵ dn h qg3Y
} .\b.l@O<Z
//int [] counts = ps.executeBatch();⑶ NS[ Z@@
conn.commit(); 7!M; ?Y
}catch(Exception e){ LphCx6f,X
e.printStackTrace(); 59.$;Ip;g
} finally{ awzlLI<2p
try{ LQF;T7VKS)
if(ps!=null) { v[$e{ Dz(
ps.clearParameters(); -RP{viGWK
ps.close(); D[>:az`
ps=null; =v3o)lU
} 7J9<B5U
}catch(SQLException e){} #VhdYDbW
DBUtils.closeConnection(conn); y;az&T
} [Q T ;~5
} \n}%RD-Ce
public long getLast(){ ,LBj$U]e|E
return lastExecuteTime; R~=c1bpdq
} z(A60b}
public void run(){ =d;a1AO{&
long now = System.currentTimeMillis(); {L$$"r,
if ((now - lastExecuteTime) > executeSep) { M(>74(}]
//System.out.print("lastExecuteTime:"+lastExecuteTime); zw3I(_d[
//System.out.print(" now:"+now+"\n"); )a^&7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ndQw>
lastExecuteTime=now; PcsYy]Q/
executeUpdate(); mU[\//
} ;1~ n|IY
else{ nKE^km
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); f#c}}>V8
} 6GuTd
} MgiW9@_(
} CV[ 9i
//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 |21VOPBS
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类写好了,下面是在JSP中如下调用。 X}GX6qAdt
rw)!>j+&A
<% zeGWM,!
CountBean cb=new CountBean(); 1Ne;U/
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); kiF}+,z"
CountCache.add(cb); IfH/~EtX
out.print(CountCache.list.size()+"<br>"); W2<'b05
CountControl c=new CountControl(); 'z91aNG]
c.run(); 5]G%MB/|$
out.print(CountCache.list.size()+"<br>"); U2`:'
%>