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: Fo (fWvz
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CountBean.java t9GR69v:?
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/* TPQ%L@^L+
* CountData.java HYD'.uj
* B-Ll{k^
* Created on 2007年1月1日, 下午4:44 s0TORl6Z|
* ,a{P4Bq
* To change this template, choose Tools | Options and locate the template under ;IvY^(YS@;
* the Source Creation and Management node. Right-click the template and choose 7JD' )
* Open. You can then make changes to the template in the Source Editor. ?8H8O %Z8
*/ ?um;s-x)
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package com.tot.count; dK$XNi13.5
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/** ('4_
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* g>E LGG|Q
* @author TM__I\+Q
*/ n$A9_cHF7
public class CountBean { Pf")e,u$
private String countType; <6%?OJhp
int countId; e-})6)XgA
/** Creates a new instance of CountData */ pTth}JM>
public CountBean() {} KC*e/J
public void setCountType(String countTypes){ y;m|
this.countType=countTypes; n K1Slg#U
} >mbHy<<
public void setCountId(int countIds){ a Yg6H2Un
this.countId=countIds; k$^UUo6
} V@.Ior}w
public String getCountType(){ 1fp?
return countType; VD;01"#'
} `f,/`''R
public int getCountId(){ F>SRs =_
return countId; H5/6TX72N
} OR P\b
} X~bX5b[P
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CountCache.java \Gef \
/*(Kr'c
/* 5ORo3T%
* CountCache.java `z}?"BW|
* yt+L0wzzB
* Created on 2007年1月1日, 下午5:01 Ye%~I`@?
* ydEoC$?0
* To change this template, choose Tools | Options and locate the template under xWH.^o,"
* the Source Creation and Management node. Right-click the template and choose ?>9/#Nv
* Open. You can then make changes to the template in the Source Editor. rET\n(AJ
*/ @W.S6;GA\
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package com.tot.count; z#9aP&8 Q
import java.util.*; etQCzYIhn
/** udK%>
* EgEa1l!NSQ
* @author dM.f]-g
*/ IV~>I-rd
public class CountCache { +zqn<<9
public static LinkedList list=new LinkedList(); 7uqzm
/** Creates a new instance of CountCache */ A;q9rD,_
public CountCache() {} 3oj' ytxN
public static void add(CountBean cb){ J/`<!$<c
if(cb!=null){ \k7"=yx
list.add(cb); #"6Qj'/h
} tH@Erh|%
} s2p\]|5
} l ~"^7H?4e
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CountControl.java olB.*#gA
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/* .D"m@~j7
* CountThread.java +yG~T
* tn\yI!a
* Created on 2007年1月1日, 下午4:57 -vo})lO
* G`D`Af/B
* To change this template, choose Tools | Options and locate the template under vQG5*pR*w
* the Source Creation and Management node. Right-click the template and choose |u% )gk
* Open. You can then make changes to the template in the Source Editor. -a}Dp~j
*/ 5+0gR
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package com.tot.count; @}u*|P*
import tot.db.DBUtils; h%na>G
import java.sql.*; AEI>\Y
/** x
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* Ys9[5@7
* @author caR<Kb:;*
*/ 79rD7D&g
public class CountControl{ .^33MWu6
private static long lastExecuteTime=0;//上次更新时间 aH(J,XY
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,Q$q=E;X
/** Creates a new instance of CountThread */ wYXQlxd y
public CountControl() {} lWk>z; d
public synchronized void executeUpdate(){ IVnHf_PzF
Connection conn=null; .bl/*s
PreparedStatement ps=null; |fJ};RLI"
try{ |)DGkOtd
conn = DBUtils.getConnection(); HXC ;Np
conn.setAutoCommit(false); sRR(`0Zp
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); G^|:N[>B
for(int i=0;i<CountCache.list.size();i++){ .[KrlfI
CountBean cb=(CountBean)CountCache.list.getFirst(); oAVnK[EMq`
CountCache.list.removeFirst(); wc@X.Q[
ps.setInt(1, cb.getCountId()); e`_LEv
ps.executeUpdate();⑴ r| wS<cA2
//ps.addBatch();⑵ s-!ArB,
} #pow ub
//int [] counts = ps.executeBatch();⑶ @Ns Qd_e
conn.commit(); w$iX.2|9%u
}catch(Exception e){ @Sn(lnlB
e.printStackTrace(); z=\&i\>;Z+
} finally{ :A_@,Q
try{ vkV0On
if(ps!=null) { WM$
MPs
ps.clearParameters(); LKB$,pR~1l
ps.close(); \;,+
ps=null; cGzPI+F
} U[-o> W#
}catch(SQLException e){} 9MJG;+B~
DBUtils.closeConnection(conn); 2%Ri,4SRb
} oG?Xk%7&\
} 3BUSv#w{i
public long getLast(){ @+2=g WH
return lastExecuteTime; !X#OOqPr=
} !;v|' I
public void run(){ Yx%Hs5}8
long now = System.currentTimeMillis(); a$OE0zn`
if ((now - lastExecuteTime) > executeSep) { X=&ET)8-Y
//System.out.print("lastExecuteTime:"+lastExecuteTime); e2TiBTbQaF
//System.out.print(" now:"+now+"\n"); 9d659iC
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); FIhk@TKa
lastExecuteTime=now; /& {A!.;
executeUpdate(); wH&!W~M
} *I.f1lz%*
else{ k@J&IJ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 20 h, ^
} '3fu
} g}{aZ$sta
} e{K 215
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ;7V%#-
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类写好了,下面是在JSP中如下调用。 nPl?K:(
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<% w+|L+h3L7
CountBean cb=new CountBean(); n0 {i&[I~+
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9wwqcx)3(
CountCache.add(cb); '[:D$q;
out.print(CountCache.list.size()+"<br>"); ~rKrpb]ow
CountControl c=new CountControl(); L|xbR#v
c.run(); s Y Qk
out.print(CountCache.list.size()+"<br>"); {rw|# Z>A
%>