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: KKWvV4u
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CountBean.java xV=Tmu6l
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/* _rmKvSD%
* CountData.java RaP,dR+P
* %E"Z &_3{
* Created on 2007年1月1日, 下午4:44 ;|:R*(2
* *%E\mu,,c
* To change this template, choose Tools | Options and locate the template under c]/S<w<
* the Source Creation and Management node. Right-click the template and choose xErb11
* Open. You can then make changes to the template in the Source Editor. ;uzLa%JQ
*/ E]=>@EX
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package com.tot.count; jx2{kK
14 (sp
/** @7KG0<]h
* 8 )n g> l
* @author ?GW}:'z
*/ ;~'& m
public class CountBean { vhcp[=e :
private String countType; M}Xf<:g)
int countId; [AA}P/iW
/** Creates a new instance of CountData */ VKf&}u/
public CountBean() {} /'b7q y
public void setCountType(String countTypes){ d[XMQX
this.countType=countTypes; "\=Phqw
} cLw|[!5:
public void setCountId(int countIds){ U]@?[+I0]
this.countId=countIds; ,]]*}4[r
} 8_"NF%%(n
public String getCountType(){ (OA4H1DL^
return countType; )4m`Ya,E3
} d`=LZio
public int getCountId(){ BRM!g9
return countId; W|y;Kxy
} D2=zrU3Y64
} b};o:
Rd|8=`)
CountCache.java OHrzN']
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/* .J O1kt
* CountCache.java j#Tl\S!m.I
* %l6E0[
* Created on 2007年1月1日, 下午5:01 c*\;!dbP
* bdG@%K',
* To change this template, choose Tools | Options and locate the template under &b7_%,Bx4
* the Source Creation and Management node. Right-click the template and choose |(.%`BTD
* Open. You can then make changes to the template in the Source Editor. OA(.&5]
*/ F\L!.B
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package com.tot.count; RBBmGZ
import java.util.*; Z!7xRy
/** 8/&4l,M5
* 51y#AQ@
* @author s~9n13z
*/ $*T?}r>
public class CountCache { >P&1or)e%
public static LinkedList list=new LinkedList(); 1@Ju sS0^K
/** Creates a new instance of CountCache */ $EX(-!c
public CountCache() {} _(I6o
public static void add(CountBean cb){ =I@I
if(cb!=null){ ]V_A4Df
list.add(cb); i^V(LGQF
} ODhq
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} xwi6#>
} c+ByEP4EG
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CountControl.java 14jN0\
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/* .Y"F3
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* CountThread.java 32j}ep.*
* rNTLP
m
* Created on 2007年1月1日, 下午4:57 C4P<GtR9
* 0;=-x"
* To change this template, choose Tools | Options and locate the template under X8R`C0
* the Source Creation and Management node. Right-click the template and choose 3?@6QcHl{
* Open. You can then make changes to the template in the Source Editor. X2rKH$<g
*/ ] _5b
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package com.tot.count; D79:L:
import tot.db.DBUtils; "WUS?Q
import java.sql.*; m[74 p
/** %^vT7c>
* 6a9$VGInU
* @author v8j3
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*/ TlRc8r|
public class CountControl{ ^|]Dg &N.
private static long lastExecuteTime=0;//上次更新时间 ~x#TfeU]
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 "=T&SY
/** Creates a new instance of CountThread */ b*M?\ aA
public CountControl() {} n P]!{J]
public synchronized void executeUpdate(){ _lFw1pa#\
Connection conn=null; l
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PreparedStatement ps=null; $2?j2}M
try{ fe,6YXUf
conn = DBUtils.getConnection(); =I)43ahd
conn.setAutoCommit(false); ~~ rR< re
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !hhL",
for(int i=0;i<CountCache.list.size();i++){ ~rJG4U
CountBean cb=(CountBean)CountCache.list.getFirst(); |E.BGdS
CountCache.list.removeFirst(); [nP s
ps.setInt(1, cb.getCountId()); /:'>-253
ps.executeUpdate();⑴ n2hV}t9O
//ps.addBatch();⑵ >( [,yMIY
} 3m`>D
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//int [] counts = ps.executeBatch();⑶ >MYDwH
conn.commit(); 9;?u%
}catch(Exception e){ ~"CGur P
e.printStackTrace(); }Mt1C~{(
} finally{ 7K:V<vX5
try{ HP1QI/*v
if(ps!=null) { (rkg0
ps.clearParameters(); bAGKi.
ps.close(); G9 O6Fi
ps=null; ow.!4kx{ d
} *^~
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}catch(SQLException e){} tmooS7\a
DBUtils.closeConnection(conn); gtZmBe=
} 4]ni-u0*
} pX?3inQP%(
public long getLast(){ v/.'st2%
return lastExecuteTime; f,KB BBbG
} cN8Fn4gq
public void run(){ 'in%Gii
long now = System.currentTimeMillis(); v#d\YV{I
if ((now - lastExecuteTime) > executeSep) { %gh#gH
//System.out.print("lastExecuteTime:"+lastExecuteTime); N}K
[Q=
//System.out.print(" now:"+now+"\n"); ?YLq
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); D5D *$IC
lastExecuteTime=now; @we1#Vz.
executeUpdate(); Mzp<s<BX
} 7MLLx#U
else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); _>Raw
} h<`aL;.g
} Y(.e e%;,
} h@!p:]
//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 hx$61E=
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类写好了,下面是在JSP中如下调用。 <f>w"r
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<% Wye* ~t
CountBean cb=new CountBean(); !m+Pd.4TaB
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >|E]??v
CountCache.add(cb); 5M0Q'"`F:
out.print(CountCache.list.size()+"<br>"); d8wVhZKI"
CountControl c=new CountControl(); 3SP";3+
c.run(); :*M?RL@j
out.print(CountCache.list.size()+"<br>"); m-vn5OX
%>