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: NOp609\^
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CountBean.java 7PkJ-JBA
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/* 2z|*xS'G
* CountData.java u?+Kkkk
* EI^06q4x
* Created on 2007年1月1日, 下午4:44 3mOtW%Hl
* H=\3Jj(4
* To change this template, choose Tools | Options and locate the template under I}t#%/'YA
* the Source Creation and Management node. Right-click the template and choose }X=[WCKU
* Open. You can then make changes to the template in the Source Editor. K3=3~uY
*/ f/V
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package com.tot.count; L@gWzC~?Q
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/** "70WUx(\t
* G8;w{-{m
* @author S*n@81Z
*/ *f?4
public class CountBean { u{*SX k
private String countType;
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int countId; mL4] l(U
/** Creates a new instance of CountData */ J2^'Xj_V
public CountBean() {} xl#LrvxI
public void setCountType(String countTypes){ }oNhl^JC
this.countType=countTypes; [h,Q Bz
} 0D&t!$Ibf
public void setCountId(int countIds){ DS)RX.k_#
this.countId=countIds; a|?4)
} >hr{JJe
public String getCountType(){ WH= EPOR,
return countType; u&n'
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} TsGE cxIg
public int getCountId(){ }6@pJG
return countId; $k2*[sn,
} tuhA
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} M`l.t -ut
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CountCache.java <^lRUw
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/* }|XtypbL
* CountCache.java Q^#;WASi
* B|&"#Q
* Created on 2007年1月1日, 下午5:01 V?=8".GiX
* 9F*+YG!
* To change this template, choose Tools | Options and locate the template under ETXZ?\<a5
* the Source Creation and Management node. Right-click the template and choose `3hSLR
* Open. You can then make changes to the template in the Source Editor. |0%+wB
*/ X3V'Cy/sy
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package com.tot.count; OdB?_.+$
import java.util.*; f4PIoZ e
/** ?'<nx{!c
* G 8V,
* @author `YIf_a{
*/ Iwc{R8BV
public class CountCache { GPGm]G t
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ YE9,KVV;$n
public CountCache() {} dtcIC0:[
public static void add(CountBean cb){ pb=cBZ$
if(cb!=null){ 7__Q1>o
list.add(cb); 4'LB7}WG
} mD/MJt5
} 7Ddaf>
} F
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CountControl.java nVI!@qW
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/* T"0,r$3:
* CountThread.java L_K=g_]
* }sOwp}FV8X
* Created on 2007年1月1日, 下午4:57 <,>P 0tY}
* H(&4[%;MP
* To change this template, choose Tools | Options and locate the template under T9879[ZU\
* the Source Creation and Management node. Right-click the template and choose >G~R,{6U
* Open. You can then make changes to the template in the Source Editor. f`&dQ,;
*/ [ U wi
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package com.tot.count; DmOyBtj
import tot.db.DBUtils; 'GL*u#h
import java.sql.*; U8G%YGMG.4
/** txPIG/
* ,Uy|5zv
* @author j7)Ao*WN
*/ b&5lY p"d
public class CountControl{ UF@XK">
private static long lastExecuteTime=0;//上次更新时间 P'O#I}Dmw<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 W[^qa5W<FB
/** Creates a new instance of CountThread */ C|?o*fQ
public CountControl() {} {U_$&f9s
public synchronized void executeUpdate(){ R?p00
Connection conn=null; m]cHF.:5
PreparedStatement ps=null; ;JRs?1<='
try{ q.()z(M7
conn = DBUtils.getConnection(); v= N!SaK{
conn.setAutoCommit(false); w&x!,yd;
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Bdu&V*0g
for(int i=0;i<CountCache.list.size();i++){ {je-I9%OK
CountBean cb=(CountBean)CountCache.list.getFirst(); Cj?L@%"
CountCache.list.removeFirst(); "^1L'4'S
ps.setInt(1, cb.getCountId()); 56Vb+0J'
ps.executeUpdate();⑴ G2^et$<{uU
//ps.addBatch();⑵ 4NdN<#Lr
} jr3ti>,xV
//int [] counts = ps.executeBatch();⑶ w/IZDMBf|
conn.commit(); Vo"RO$%ow*
}catch(Exception e){ ^'ryNa;"
e.printStackTrace(); zrU{@z$l
} finally{ Usta0Ag
try{ uZ=NSbYsA
if(ps!=null) { H/"lAXfb
ps.clearParameters(); v%RP0%%{s
ps.close(); A2nqf^b{#
ps=null; is@b&V]
} p}<w#p
|
}catch(SQLException e){} ~jb"5CX
DBUtils.closeConnection(conn); ]J#9\4Sq
} nQ/E5y
} 25&J7\P*
public long getLast(){ |eWjYGwJa
return lastExecuteTime; mSo_} je(
} SC-
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public void run(){ UDL
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long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { q`G, L(
//System.out.print("lastExecuteTime:"+lastExecuteTime); +/ &_v^sC;
//System.out.print(" now:"+now+"\n"); "$}vP<SM
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "XT"|KF|D
lastExecuteTime=now; 1\r|g2Z
:
executeUpdate(); 9Fr3pRIJ
} po}F6m8bX
else{ 6AWKLFMV
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {N#KkYH{"
} DSj(]U~r
} YQS5P#
} i>joT><B
//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 @e'5E^
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类写好了,下面是在JSP中如下调用。 L=8+_0
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<% i:l<C
CountBean cb=new CountBean(); ":nQgV\9
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $*W6A/%O
CountCache.add(cb); ~M(5Ho
out.print(CountCache.list.size()+"<br>"); _fwb!T}$
CountControl c=new CountControl(); h/,${,}J
c.run(); JO@|*/mL
out.print(CountCache.list.size()+"<br>"); LE%7DW(
%>