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: 0iKAg
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CountBean.java l!:L<B
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/* .&n!4F'
* CountData.java 'Jd*r(2d
* kpMo7n
* Created on 2007年1月1日, 下午4:44 #!P>.".
* v=DC3oh-
* To change this template, choose Tools | Options and locate the template under u R]8ZT")
* the Source Creation and Management node. Right-click the template and choose Dn`
* Open. You can then make changes to the template in the Source Editor. T>,[V:
*/ V/RV,K1/
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package com.tot.count; PoLk{{l3
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/** |3>%(4
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* rx@2Dmt6
* @author 4jzjrG
*/ 77'@U(
public class CountBean { YR[I,j
private String countType; 9xeg,#1
int countId; {
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/** Creates a new instance of CountData */ mdlMciP
public CountBean() {} vSo1WS
public void setCountType(String countTypes){ *hh9
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this.countType=countTypes; r6It)PQ
} :es=T`("A8
public void setCountId(int countIds){ Cv;#8Wj}
this.countId=countIds; JD9=gBN\?
} N;4wbUPL7h
public String getCountType(){ B &3sV+
return countType; Kaji&Ibd
} m=a^t
public int getCountId(){ a'O-0]g,
return countId; JW"n#sR4
} Bve',.xH
} eV"Uv3
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CountCache.java .UvDew/Y
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/* ((M>To_l
* CountCache.java 2s}G6'xE]P
* MjbgAH-
* Created on 2007年1月1日, 下午5:01 QY*F(S,\
* M^G9t*I
* To change this template, choose Tools | Options and locate the template under QQD7NN>
* the Source Creation and Management node. Right-click the template and choose x:c'ek
* Open. You can then make changes to the template in the Source Editor. )5u#'5I>
*/ .R^ R|<x
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package com.tot.count; Z:diM$Z?7
import java.util.*; :k2J
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/** 0qm CIcg
* h-U]?De5\
* @author KL"_h`UW
*/ 6q,CEm
public class CountCache { Y Azj>c&
public static LinkedList list=new LinkedList(); dJ>tM'G
/** Creates a new instance of CountCache */ OHv9|&Tpl
public CountCache() {} 2'Raj'2S4
public static void add(CountBean cb){ }0]iS8*tL
if(cb!=null){ 0v``4z2Z
list.add(cb); P G
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} I:1Pz|$`
} W*/2x8$d
} gLlA'`!
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CountControl.java <RcB: h
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/* !e+Sa{X
* CountThread.java M~)iiKw~MY
* W{1l?Wo
* Created on 2007年1月1日, 下午4:57 8"rK
* -![{Zb@
* To change this template, choose Tools | Options and locate the template under V0n8fez
b
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor.
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*/ r]Lj@0F>8
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package com.tot.count; "V5_B^Gzb]
import tot.db.DBUtils; m8INgzVTC
import java.sql.*; - %?>1n
/** w:](F^<s,
* v~0lZe
* @author 5@n|uJA
*/ Q8_5g$X\
public class CountControl{ !uA'0U?ky
private static long lastExecuteTime=0;//上次更新时间 c?6(mU\x
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 .(s@{=
/** Creates a new instance of CountThread */ i_nUyH%b
public CountControl() {} `%~f5<
public synchronized void executeUpdate(){ +e#(p<
Connection conn=null; /=QsZ,~xo
PreparedStatement ps=null; Wxgs66
try{ =@nW;PUZ
conn = DBUtils.getConnection(); G0Z$p6z
conn.setAutoCommit(false); s !II}'Je
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ]qx!51S
for(int i=0;i<CountCache.list.size();i++){ ^;$9>yi1
CountBean cb=(CountBean)CountCache.list.getFirst(); v7v>
CountCache.list.removeFirst(); C;ME"4,(
ps.setInt(1, cb.getCountId()); |w -s{L3@+
ps.executeUpdate();⑴ &E@mCQ1
//ps.addBatch();⑵ nN>Uh T
} 2#8PM-3"
//int [] counts = ps.executeBatch();⑶ {;o54zuKf
conn.commit(); [hqat'Vj,
}catch(Exception e){ n.,ZgLx["
e.printStackTrace(); ClufP6'
} finally{ ^c"\%!w"O
try{ F5{GMn;j
if(ps!=null) { rLbFaLeQ
ps.clearParameters(); AP9\]qZ(7
ps.close(); ssmJ?sl
ps=null; qj^A
} cca]@Ox]
}catch(SQLException e){} ;a[3RqmKW
DBUtils.closeConnection(conn); 1yeD-M"w
} Djf~8q V!
} Z*(OcQ-
public long getLast(){ bNoZ{ 7
return lastExecuteTime; gL1r"&^L
} ObataUxQT
public void run(){ Ko
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long now = System.currentTimeMillis(); \?^ EFA+;
if ((now - lastExecuteTime) > executeSep) { S)"vyGv
//System.out.print("lastExecuteTime:"+lastExecuteTime); i,L"%q)C
//System.out.print(" now:"+now+"\n"); NkQain9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); l a_
lastExecuteTime=now; L>N)[;|
executeUpdate(); R5 EC/@
} /q!_f!<q4x
else{ EPM(hxCIQ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); S-brV\v7
} :]* =f].
} e)i-$0L"
} K%SfTA1TCB
//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 p4K
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类写好了,下面是在JSP中如下调用。 |+=ctpx9&
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<% clr]gib
CountBean cb=new CountBean(); Z
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Ge24Lp;Y6
CountCache.add(cb); o/!a7>xO4
out.print(CountCache.list.size()+"<br>"); C%P.`Nx A
CountControl c=new CountControl(); 7f~7vydZ}
c.run(); + Cq&~<B
out.print(CountCache.list.size()+"<br>"); iT1HbAT]
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