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: Jzqv6A3G
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CountBean.java ~`7L\'fs
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/* mIJYe&t7)
* CountData.java I)@b#V=
* x.d;7
* Created on 2007年1月1日, 下午4:44 |UA)s3Uhxb
* :aYbP,mE
* To change this template, choose Tools | Options and locate the template under 1: cD\
* the Source Creation and Management node. Right-click the template and choose Ns^[Hb[b'
* Open. You can then make changes to the template in the Source Editor. & ,KxE(C
*/ njO5 YYOu
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package com.tot.count; AQCU\E
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/** KW&5&~)2
* J|vriI;
* @author Qyn~Vu43
*/ Mp8BilH-T
public class CountBean { lO?dI=}]
private String countType; 0taopDi;d
int countId; aTJs.y-I~
/** Creates a new instance of CountData */ ?V3kIb
public CountBean() {} ;xp^FKP
public void setCountType(String countTypes){ +mc0:e{WF
this.countType=countTypes; f@:.bp8VB8
} -Xm/sq(i)%
public void setCountId(int countIds){ N{6
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this.countId=countIds; $:v!*0/
} e!+_U C
public String getCountType(){ HzdtR
return countType; $kc*~V~
} 3zV{cm0
public int getCountId(){ B?;!j)FUtt
return countId; <$#;J>{WV
} (%`R{Y
} gpo+-NnG
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CountCache.java irg%n
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/* U
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* CountCache.java I/F3%'O
* l!6^xMhYk
* Created on 2007年1月1日, 下午5:01 uif1)y`Q$C
* z%$,F9/
* To change this template, choose Tools | Options and locate the template under &f2'cR
* the Source Creation and Management node. Right-click the template and choose )U>JFgpIW
* Open. You can then make changes to the template in the Source Editor. Ucj
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*/ }3{ x G+,
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package com.tot.count; *^]lFuX\&E
import java.util.*; Us5P?}
/** U9uy(KOW
* ups]k?4
* @author #!a}ZhIt
*/ fu}ZOPu
public class CountCache { +W{ELdup%q
public static LinkedList list=new LinkedList(); Het5{Yb.
/** Creates a new instance of CountCache */ h[%t7qo=
public CountCache() {} O@$wU9D<
public static void add(CountBean cb){ ]!v:xjzT
if(cb!=null){ @vy{Q7aM
list.add(cb); 9DAk|K
} F;I % 9-R
} ynWF Y<VX
} ukZ>_ke`+
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CountControl.java ]<9KX} B
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/* Wmm'j&hI
* CountThread.java ,5tW|=0@
* 3,x|w
* Created on 2007年1月1日, 下午4:57 8&gr}r-
5
* #n9:8BKf
* To change this template, choose Tools | Options and locate the template under .BaU}-5
* the Source Creation and Management node. Right-click the template and choose )Ha`>
* Open. You can then make changes to the template in the Source Editor. "4 Lt:o4x
*/ Qxw?D4/Y
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package com.tot.count; y;M}I8W[
import tot.db.DBUtils; {$dq7m(
import java.sql.*; tEj-c@`"x-
/** Oa8lrP`(
* e:&+m `OSH
* @author ~M>EB6
*/ FCk4[qOp7
public class CountControl{ |U~m8e&:
private static long lastExecuteTime=0;//上次更新时间 8$c_M
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 QT!!KTf
/** Creates a new instance of CountThread */ ?1+JBl~/d
public CountControl() {} 'G6M:IXno
public synchronized void executeUpdate(){ dtXAEL\q
Connection conn=null; Jp'XZ]o\
PreparedStatement ps=null; +Wr"c
try{ LF2@qv w D
conn = DBUtils.getConnection(); 'dkKBLsx
conn.setAutoCommit(false); fj/sN HU
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Myal3UF
for(int i=0;i<CountCache.list.size();i++){ 51,RbADB
CountBean cb=(CountBean)CountCache.list.getFirst(); l6YToYzE2
CountCache.list.removeFirst(); =V)88@W
ps.setInt(1, cb.getCountId()); BA1|%:.
ps.executeUpdate();⑴ M9_G
//ps.addBatch();⑵ `PV+.V}
} C4Tn
//int [] counts = ps.executeBatch();⑶ 3 &aBU[
conn.commit(); /b$0).fj@,
}catch(Exception e){ fmDn1N-bG
e.printStackTrace(); 2l7Sbs7
} finally{ /b44;U`v5-
try{ 'aq9]D_k
if(ps!=null) { Z~JX@s0v
ps.clearParameters(); lphELPh
ps.close(); \0{g~cU4
ps=null; 6m=FWw3y
} $p(,Qz(.8
}catch(SQLException e){} \[nvdvJv
DBUtils.closeConnection(conn); NXJyRAJ*%
} d]kP@flOV
} -G!W6$Y
public long getLast(){ @[:JQ'R=
return lastExecuteTime; li U=&wM>
} 5|4=uoA<
public void run(){ cz2guUu
long now = System.currentTimeMillis(); ,b&-o?.{
if ((now - lastExecuteTime) > executeSep) { I3{koI
//System.out.print("lastExecuteTime:"+lastExecuteTime); 1l8kuwH
//System.out.print(" now:"+now+"\n"); u-31$z<<5}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); e:h(,
lastExecuteTime=now; POnI&y]
executeUpdate(); SkmL X@:(
} M-K.[}}-d
else{ -<R"
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); L\:f#b~W
} SGZ]_
} H1FD|Q3
} r35'U#VMk?
//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 ~miRnW*x
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类写好了,下面是在JSP中如下调用。 P ~pC /z
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<% 7]i=eD8
CountBean cb=new CountBean(); X_j=u1*5
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 3eq VY0q
CountCache.add(cb); vlHE\%{
out.print(CountCache.list.size()+"<br>"); x6d0yJ <
CountControl c=new CountControl(); d )}@0Q
c.run(); *=6,}rX"I
out.print(CountCache.list.size()+"<br>"); /7bIE!Cn
%>