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: Yp;?Zq9
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CountBean.java %<^j=K= 0
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/* BKd?%V8:Q
* CountData.java j4}Q
* V5bB$tL}3
* Created on 2007年1月1日, 下午4:44 LHd9q^D
* *w[0uQL5Z
* To change this template, choose Tools | Options and locate the template under NbUbLzE
* the Source Creation and Management node. Right-click the template and choose Eanwk` Rx
* Open. You can then make changes to the template in the Source Editor. "{M?,jP#
*/ v]hu5t
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package com.tot.count; @5*$yi 'Cp
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/** -s9()K(vZG
* #,Cz+k*4
* @author j},3@TFh
*/ 9
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public class CountBean { ygYy [IZ
private String countType; J)P7QTC
int countId; QeG3X+
/** Creates a new instance of CountData */ cng166}1A
public CountBean() {} EfGy^`,'G
public void setCountType(String countTypes){ 80 ckh
this.countType=countTypes; OzAxnd\.N
} A/ 88WC$v
public void setCountId(int countIds){ $Ahe Vps@@
this.countId=countIds; G]O5irsV
} N%!{n7`N:
public String getCountType(){ w
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return countType; q0VR&b`?>D
} _~O*V&
public int getCountId(){ c[a^fu!
return countId; c]R27r E
} N}KL'
} ^JAp#?N^9
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CountCache.java C{OkbE"Vym
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/* puox^
* CountCache.java $) m$c5!
* '+7"dHLC;
* Created on 2007年1月1日, 下午5:01 1G)I|v9R
* w/csLi.O
* To change this template, choose Tools | Options and locate the template under 2 :wgt
* the Source Creation and Management node. Right-click the template and choose 0HN%3AG]
* Open. You can then make changes to the template in the Source Editor. %{ory5
*/ pKaU
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package com.tot.count; u9N/9
import java.util.*; <."KejXg-
/** kO4'|<
* Y-lTPR<Eq
* @author G%viWWTY
*/ (@V_47o
public class CountCache { b*1yvkX5
public static LinkedList list=new LinkedList(); q1Mt5O}
/** Creates a new instance of CountCache */ *auT_*
public CountCache() {} 1@n'6!]6O
public static void add(CountBean cb){ v Q,<Ke+d
if(cb!=null){ :Q8*MJ3&V
list.add(cb); KkCsQ~po
} wlgR =l
} D!&]jkUN
} F ESl#.}
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CountControl.java r+;k(HMY}[
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/* NuW6~PV
* CountThread.java hR~&}sxN
* /}9)ZYMx
* Created on 2007年1月1日, 下午4:57 )YW"Zo8~!1
* G|u)eW
* To change this template, choose Tools | Options and locate the template under wsB
* the Source Creation and Management node. Right-click the template and choose "RgP!
* Open. You can then make changes to the template in the Source Editor. AkCy
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*/ !,]2.:{0z
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package com.tot.count; oX7_v_:J\R
import tot.db.DBUtils; oRZe?h^r#
import java.sql.*; 6j95>} @
/** '}IGV`c
* !*S,S{T8
* @author aW9\h_$
*/ xjD."q
public class CountControl{ ~O|~M_Z
private static long lastExecuteTime=0;//上次更新时间 kPoz&e_@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 I51I(QF=
/** Creates a new instance of CountThread */ *7b?.{
public CountControl() {} nw(R=C
public synchronized void executeUpdate(){ u U%Z%O
Connection conn=null; QseV\; z
PreparedStatement ps=null; W8F@nY
try{ sR/y|
conn = DBUtils.getConnection(); 'x5p ?m
conn.setAutoCommit(false); *W;;L_V"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); sf/m@425
for(int i=0;i<CountCache.list.size();i++){ TbLU[(m-n
CountBean cb=(CountBean)CountCache.list.getFirst(); ~'F.tB
CountCache.list.removeFirst(); 4U~'Oa@p
ps.setInt(1, cb.getCountId()); <KfR)7I$0a
ps.executeUpdate();⑴ L/In~'*-
//ps.addBatch();⑵ W]XM<# ^^
} 2_ 1RJ
//int [] counts = ps.executeBatch();⑶ [w!T
conn.commit(); iiF`2
}catch(Exception e){ q" EW*k+
)
e.printStackTrace(); e N v\ZR1
} finally{ n.t5:SW
try{ ;M~9Yr=1
if(ps!=null) { a,(nf1@5
ps.clearParameters();
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ps.close(); #%w+PL:*O
ps=null; maeQ'Sv_&
} oY0*2~sg
}catch(SQLException e){} t2Jf+t_B7
DBUtils.closeConnection(conn); c91^7@Xv
} %|D)U>o{
} Zu2`IzrG#
public long getLast(){ wE"lk
return lastExecuteTime; MV2$0
} \Zh&[D!2
public void run(){ KDP"z
long now = System.currentTimeMillis(); iJj!-a:z.
if ((now - lastExecuteTime) > executeSep) { w}#3 pU<<
//System.out.print("lastExecuteTime:"+lastExecuteTime); UBJYs{zz
//System.out.print(" now:"+now+"\n"); W?"l6s
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?XP4kjJ
lastExecuteTime=now; P(DEf(
executeUpdate(); w]nt_xj
} #%F-Xsk
else{ dm]g:KWg
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); JdLPIfI^
} 9HEqB0|ZRu
} 7r^Cs#b+I
} !3iZa*
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 IaQm)"Z
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类写好了,下面是在JSP中如下调用。 *JfGGI_E
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<% LT>_Y`5>
CountBean cb=new CountBean(); hW'b'x<
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); v\CBw"
CountCache.add(cb); ."gq[0_YS
out.print(CountCache.list.size()+"<br>"); j}d):3!
CountControl c=new CountControl(); mZc; n.$U
c.run(); wEwRW
out.print(CountCache.list.size()+"<br>"); $${3I4
%>