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: ]1d)jWG
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CountBean.java d$bO.t5CLh
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/* ,e;,+w=~E
* CountData.java @S}j=k
* n/Fxjf0W
* Created on 2007年1月1日, 下午4:44 )z@
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* uKM` umE
* To change this template, choose Tools | Options and locate the template under {S9gOg
* the Source Creation and Management node. Right-click the template and choose ,
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* Open. You can then make changes to the template in the Source Editor. Ji9o0Y R
*/ $fD%18
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package com.tot.count; nKr'cb
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/** ;
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* T5ky:{Y(
* @author R$
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*/ h~Z &L2V
public class CountBean { zc;kNkV#1Y
private String countType; KO#kIM-
int countId;
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/** Creates a new instance of CountData */ kJf0..J[#<
public CountBean() {} 8\'tfHL
public void setCountType(String countTypes){ hOZTD0
this.countType=countTypes; Eze w@*(
} >"<s7$g
public void setCountId(int countIds){ w/(T
this.countId=countIds; Nh^I{%.x
} !9$}1_,is
public String getCountType(){ db_?da;!`
return countType; R0*P,~L;|
} {-m e;ayk
public int getCountId(){ @^ YXE,
return countId; cRr3!<EZ
} ;r"r1'a+@
} %gFIu.c
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CountCache.java e#h&Xa
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/* Qfy_@w]
* CountCache.java z,m3U(
* i_AD3Jrs
* Created on 2007年1月1日, 下午5:01 Y96<c" t
* eF{uWus
* To change this template, choose Tools | Options and locate the template under v+Y^mV`|
* the Source Creation and Management node. Right-click the template and choose AU`z.Isf
* Open. You can then make changes to the template in the Source Editor. yQj J-g(.
*/ af>i
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package com.tot.count; 2'M5+[8y8
import java.util.*; c)^A|{,G
/** AhOBbss]q
* v}t{*P
* @author v*GS>S
*/ dZ(Z]`L,B
public class CountCache { )hO%W|
public static LinkedList list=new LinkedList(); k}<H
/** Creates a new instance of CountCache */ l}^ziY!
public CountCache() {} =#9#unvE!
public static void add(CountBean cb){ ,.*Df)+
if(cb!=null){ yY UAH-
list.add(cb); j1{`}\e
} }6%\/d1~ 6
} V*te8HIe
} zsQkI@)sO
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CountControl.java Y)]VlV!`
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/* =GP L>a&
* CountThread.java k CGb~+
* ATc!c +
* Created on 2007年1月1日, 下午4:57 uQ[,^Ee&/
* ]SU)L5Dt;
* To change this template, choose Tools | Options and locate the template under }\8-&VoY#X
* the Source Creation and Management node. Right-click the template and choose 6o6yx:
* Open. You can then make changes to the template in the Source Editor. fI0"#iv}
*/ |?0MRX0'g
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package com.tot.count; 0H +nVR
import tot.db.DBUtils; Rh"O$K~
import java.sql.*; _$IWr)8f
/** 2&:z[d}~H
* )3e_Hs+
* @author oupWzjo
*/ yxpv;v:)=
public class CountControl{ ceks~[rP
private static long lastExecuteTime=0;//上次更新时间 o!+'<IQ'
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !fAvxR
/** Creates a new instance of CountThread */ + XBF,<P
public CountControl() {} A ?V-Sz#
public synchronized void executeUpdate(){ v
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Connection conn=null; [W$Mn.5<s
PreparedStatement ps=null; )_ !a:
try{ S#p_Y^A
conn = DBUtils.getConnection(); z0ufLxq
conn.setAutoCommit(false); Il@K8?H@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); x@oxIXN
for(int i=0;i<CountCache.list.size();i++){ 7#UJ444b~
CountBean cb=(CountBean)CountCache.list.getFirst(); r 56~s5A
CountCache.list.removeFirst(); kkHK~(>G
ps.setInt(1, cb.getCountId()); _I'k&R
ps.executeUpdate();⑴ y7#+VF`xf
//ps.addBatch();⑵ k3B_M9>!
} ;t9_*)[
//int [] counts = ps.executeBatch();⑶ 4NaT@68p
conn.commit(); oaq,4FT
}catch(Exception e){ ^2rj);{V
e.printStackTrace(); }I}GA:~$%
} finally{ { GCp5
try{ v.:Q& ]
if(ps!=null) { `/R. 5;$|
ps.clearParameters(); z$m(@Q
ps.close(); w0$+v/
ps=null; Gb[J3:.
} #G0'Q2
}catch(SQLException e){} ~0-)S@
DBUtils.closeConnection(conn); pl,XS6mB
} j&S.k
} 16I[z+RG
public long getLast(){ 9&^5!R8
return lastExecuteTime; X[<#B5
} J#@+1 Nt
public void run(){ e&ZTRgYdi
long now = System.currentTimeMillis(); a[zVC)N0
if ((now - lastExecuteTime) > executeSep) { 525^/d6v
//System.out.print("lastExecuteTime:"+lastExecuteTime); N|)e {|k
//System.out.print(" now:"+now+"\n"); s-SFu
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Z)(#D($-
lastExecuteTime=now; jYAm}_?No
executeUpdate(); ZWuNl!l>
} INk|NEX
else{ Snmv
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 3My}u>
} j<Pw0?~s6
} [N[4\W!!
} 0lq?l:/
//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 p_n$}z
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类写好了,下面是在JSP中如下调用。 ~n0Exw(
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<% QjpJIw
CountBean cb=new CountBean(); Fpn'0&~-fi
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ?AxB0d9z
CountCache.add(cb); ]1GyEr:
out.print(CountCache.list.size()+"<br>"); D2o|.e<r
CountControl c=new CountControl(); dW5r]D[Cx
c.run(); zU0JwZi
out.print(CountCache.list.size()+"<br>"); (C`nBiL<
%>