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: XM1WfjE\
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CountBean.java LO
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/* *RXbc~
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* CountData.java `&KwtvkdI
* vY%d
* Created on 2007年1月1日, 下午4:44 9{-EJ)
* vWRju*Z&
* To change this template, choose Tools | Options and locate the template under wT `a3Ymm
* the Source Creation and Management node. Right-click the template and choose j<u@j+V
* Open. You can then make changes to the template in the Source Editor. T?
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*/ ])L
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package com.tot.count; 5"HVBfFk
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/** t"k*PA
* -M[$Z y^
* @author q8^^H$<Db
*/ %F!1
public class CountBean { jgbLN/_{
private String countType; G>wqt@%r9
int countId; twP,cyR
/** Creates a new instance of CountData */ lz"OC<D}(
public CountBean() {} BlXB7q,
public void setCountType(String countTypes){ }RmU%IYc
this.countType=countTypes; pcYG~pZ9
} IkBei&4F`
public void setCountId(int countIds){ !'mq ?C=
this.countId=countIds; _acE:H
} 0Uz\H0T1
public String getCountType(){ UG2nX3?
return countType; ROk5]b.
} ?\$#L^;b}
public int getCountId(){ XLAN Np%E
return countId; FP;Ccl"s
} @r#v[I
} 5D_fXfx_|
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CountCache.java et,f_fd7v
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/* Uc_'(IyO
* CountCache.java Z7_m)@%;kk
* "NgxkbDEbG
* Created on 2007年1月1日, 下午5:01 tcLnN:
* 3E>frR\!I
* To change this template, choose Tools | Options and locate the template under !R1.7}O
* the Source Creation and Management node. Right-click the template and choose !eEHmRgg4
* Open. You can then make changes to the template in the Source Editor. |`lzfe
*/ kMtwiB|7j
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package com.tot.count; ag*mG*Z
import java.util.*; m9" n4a|:
/**
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* Eo#u#IY
* @author Q(<)KZIK
*/ VJdIHsI
public class CountCache { 0JlZs]
public static LinkedList list=new LinkedList(); r :F
/** Creates a new instance of CountCache */ /C>wd
public CountCache() {} t?9v^vFR
public static void add(CountBean cb){ Q\cjPc0y
if(cb!=null){ |4T!&[r
list.add(cb); E-I-0h2
} 6`]$qSTS
} A8pIs
} xKQ+{"?-^g
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CountControl.java gF$V$cU
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/* f}1&HI8r
* CountThread.java :{IO=^D=$
* l-ct?T_@
* Created on 2007年1月1日, 下午4:57 &_"]5/"(
* N5i+3&
* To change this template, choose Tools | Options and locate the template under Dh5X/y
* the Source Creation and Management node. Right-click the template and choose H63,bNS s
* Open. You can then make changes to the template in the Source Editor. \/1<E?Q
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*/ Td G!&:>
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package com.tot.count; ]3g?hM6
import tot.db.DBUtils; E I:w
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import java.sql.*; PB#fP_0C
/** mml<9fbH
* UN zlN
* @author _cc#Qlw 7
*/ sVJ!FC
public class CountControl{ *e-A6Sh
private static long lastExecuteTime=0;//上次更新时间 Q8DQlqHm
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;_^fk&+
/** Creates a new instance of CountThread */ |b-]n"}c>
public CountControl() {} Eh|]i;G%
public synchronized void executeUpdate(){ G.(mp<-
Connection conn=null; |37
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PreparedStatement ps=null; *,Za6.=
try{ w9o^s5n
conn = DBUtils.getConnection(); e _/b2"{
conn.setAutoCommit(false); w~
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); f|R"uW +
for(int i=0;i<CountCache.list.size();i++){ 'A:x/iv}^
CountBean cb=(CountBean)CountCache.list.getFirst(); %K>.lh@
CountCache.list.removeFirst(); [o.B
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ 'k4E4OB
//ps.addBatch();⑵ 4H|(c[K;
} xj[(P$,P
//int [] counts = ps.executeBatch();⑶ R1& [S/
conn.commit(); BQ @huns3
}catch(Exception e){ T'LIrf
e.printStackTrace(); sgO'wXcoP
} finally{ +reor@h
try{
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if(ps!=null) { v@wb"jdFi$
ps.clearParameters(); [+OnV&
ps.close(); "R3d+p
ps=null; kI:}| _
} qQ0cJIISb\
}catch(SQLException e){} \mV'mZ9>
DBUtils.closeConnection(conn); 4E+hRKuo,
} KyzFnVH3)
} ^b 7GH9<&
public long getLast(){ Tp0bS
return lastExecuteTime; .N*Pl(<[
} VMCLHpSfW
public void run(){ ({NAMc*
long now = System.currentTimeMillis(); dlG=Vq&Y
if ((now - lastExecuteTime) > executeSep) { jS]><rm
//System.out.print("lastExecuteTime:"+lastExecuteTime); =IUUeFv +r
//System.out.print(" now:"+now+"\n"); _>v<(7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); fgBM_c&9T
lastExecuteTime=now; c7M%xGrP
executeUpdate(); !w H'b
} `\m*+Bk[5
else{ i| ZceX/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); >5j<4ShW
}
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} !YP@m~
} n_B"-n
//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 La@
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类写好了,下面是在JSP中如下调用。 ;L,mBQB?0b
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<% ]>+PnP35G
CountBean cb=new CountBean(); Z*])6=2Q
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $DZHQH
CountCache.add(cb); bO&7-Z~:=
out.print(CountCache.list.size()+"<br>"); aDehqP6vf
CountControl c=new CountControl(); @c~)W8
c.run(); y2+p1
out.print(CountCache.list.size()+"<br>"); ^mb[j`CCt
%>