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: }i._&x`):
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CountBean.java z94#:jPmG
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/* o4U0kiI@
* CountData.java 8B!MgNKV
* C&HN#Q_
* Created on 2007年1月1日, 下午4:44 zt;aB>jz#
* Q2qT[aD,
* To change this template, choose Tools | Options and locate the template under *Za'^ Z2
* the Source Creation and Management node. Right-click the template and choose AcP d(Pc
* Open. You can then make changes to the template in the Source Editor. ?k`UQi]Q
*/ 'D'H)J
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package com.tot.count; H7FOf[3'
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/** u.ej<Lo
* !mH
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* @author uN&UYJ'B
*/ :'2h0
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public class CountBean { R =kXf/y
private String countType;
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int countId; xL [3R
/** Creates a new instance of CountData */ mor[AJ
public CountBean() {} +wp !hk&C5
public void setCountType(String countTypes){ 1z3>nou2{
this.countType=countTypes; fG zx;<0P!
} <
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public void setCountId(int countIds){ ~jJF&*)
this.countId=countIds; /%1-tGh
} zJ)`snN|
public String getCountType(){ % oJH 6F
return countType; ]TVc 'G;
} _1G;!eO
public int getCountId(){ ra;:
return countId; 4s9qQ8?
} m
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} a$K6b5`>Rs
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CountCache.java +2+|zXmT
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/* "m>BE
* CountCache.java 4Ss*h,Y
* Qe =8x7oIP
* Created on 2007年1月1日, 下午5:01 kho$At)V
* ;b}cn!U]
* To change this template, choose Tools | Options and locate the template under (3WK2IM^
* the Source Creation and Management node. Right-click the template and choose Ji.FG"h+2
* Open. You can then make changes to the template in the Source Editor. {b|V;/
*/ Q[c:A@oW
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package com.tot.count; s.^+y7$
import java.util.*; Th
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/** .oM;D~(=9
* vRb7=fXf
* @author lWDSF]ZYV
*/ }Te+Rv7{E
public class CountCache {
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public static LinkedList list=new LinkedList(); (&-I-#i
/** Creates a new instance of CountCache */ eus@;l*
public CountCache() {} D+u\ORj
public static void add(CountBean cb){ t>P[Yld"
if(cb!=null){ G<P/COI#M5
list.add(cb); %GP`H/H(
} !?" pnKb}
} =om<* \vsO
} +&r=XJ5:`p
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CountControl.java Tol V3
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/* GX'S4B
* CountThread.java 1,Jy+1G0w
* >y+?Sz!
* Created on 2007年1月1日, 下午4:57 @O/"s~d-
* Wr@q+Whq
* To change this template, choose Tools | Options and locate the template under ,#bT
* the Source Creation and Management node. Right-click the template and choose >,.\`.0
* Open. You can then make changes to the template in the Source Editor. '|}H,I{
*/ /.(~=6o5
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package com.tot.count; l,5isq
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import tot.db.DBUtils; h1y3gl[;TD
import java.sql.*; {mY=LaS<
/** =3nA5'UZ
* `a[
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* @author j)wrF@W
*/ 7[0<,O6Q
public class CountControl{ ?w&?P}e +
private static long lastExecuteTime=0;//上次更新时间 dkW7k^g
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ve\@u@K^
/** Creates a new instance of CountThread */ (Vn3g ra
public CountControl() {} |tC= j.
public synchronized void executeUpdate(){ nt@uVwfQ
Connection conn=null; N;DE,[:<
PreparedStatement ps=null; fymmAfaR
try{
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conn = DBUtils.getConnection(); mKoDy`s
conn.setAutoCommit(false); i*8j|
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); l3+G ]C&<
for(int i=0;i<CountCache.list.size();i++){ 3sgo5D-rMI
CountBean cb=(CountBean)CountCache.list.getFirst(); (:^YfG~e
CountCache.list.removeFirst(); {P3gMv;
ps.setInt(1, cb.getCountId()); %_G '#Bn<
ps.executeUpdate();⑴ sX]gL
//ps.addBatch();⑵ K"!U&`T
} t qUBl?i
//int [] counts = ps.executeBatch();⑶ Zq'FOzs
conn.commit(); cG (%P$
}catch(Exception e){ zcuz @
e.printStackTrace(); {b-SK5%]L
} finally{ nkz<t
try{ xVrLoAw
if(ps!=null) { ]z2x`P^oI
ps.clearParameters(); F$'po#
ps.close(); KO/#t~
ps=null; ^)o]hE|
} B`w8d[cL7
}catch(SQLException e){} a|DCpU}
DBUtils.closeConnection(conn); IpM"k)HR
} )NTpb
} XjmAM/H4
public long getLast(){ eep/96G
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return lastExecuteTime; %TO&
} VF +g+~
public void run(){ q^uCZnkb=
long now = System.currentTimeMillis(); NZlCn:"
if ((now - lastExecuteTime) > executeSep) { [!Djs![O
//System.out.print("lastExecuteTime:"+lastExecuteTime); -0I&dG-
//System.out.print(" now:"+now+"\n"); b!`6s
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1@}<CWE9
lastExecuteTime=now; ftQ;$@
executeUpdate(); HG)$W
} 'Hgk$Im+
else{ Zad>iw}
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); S_^;#=_c
} =iB$4d2
} Pb1.X9*8c
} EztuVe
//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 k2.\1}\
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类写好了,下面是在JSP中如下调用。 e.Jaq^Gw|
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<% wa!z:}]
CountBean cb=new CountBean(); i2-]Xl
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =4L%A=]`
CountCache.add(cb); `-Tb=o}.
out.print(CountCache.list.size()+"<br>"); MwL!2r
CountControl c=new CountControl(); /7ShE-.5#
c.run(); F&Rr&m
out.print(CountCache.list.size()+"<br>"); 79D;0
%>