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: 2ku\R7
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CountBean.java WjtmV2b<7
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/* a=\r~Z7E
* CountData.java }7E2,A9_"
* GL'zs8AKf
* Created on 2007年1月1日, 下午4:44 !},_,J~(|
* 0|n1O)>J
* To change this template, choose Tools | Options and locate the template under 0dA'f0Uy\X
* the Source Creation and Management node. Right-click the template and choose sI/Jhw)
* Open. You can then make changes to the template in the Source Editor. zl\mBSBx"
*/ (gZKR2hO
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package com.tot.count; >8+:{NW
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/** fEF1&&8^
*
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* @author x;2tmof=L
*/ u{maE ,
public class CountBean { 4~=/CaG~
private String countType; V9qA.NV2
int countId; ,[&@?
/** Creates a new instance of CountData */ [f,; +Ze
public CountBean() {} ZW
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public void setCountType(String countTypes){ 8.bIP
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this.countType=countTypes; W>+\A"
} >.N?y@
public void setCountId(int countIds){ VeidB!GyP
this.countId=countIds; cLn&b}8'
} ~#+ Hhc(
public String getCountType(){ `)$'1,]u
return countType; G4][`C]8c
} 5]DgfwX
public int getCountId(){ -t2bHhG
return countId; zts%oIgV
} HM ;9%rtO
} +]P??`,R;
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CountCache.java f"j~{b7
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/* OI</o0Ca
* CountCache.java 1TeYA6 t
* zLdi
* Created on 2007年1月1日, 下午5:01 )e`$'y@L$
* Xl^=&!S>me
* To change this template, choose Tools | Options and locate the template under =Is.T
* the Source Creation and Management node. Right-click the template and choose v:kTZB
* Open. You can then make changes to the template in the Source Editor. ["VUSa
*/ NrPs :`
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package com.tot.count; zsnXPRF
import java.util.*; WVl yR\.
/** _Vr>/f
* ;2-%IA,
* @author
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*/ [h20y
public class CountCache { -E_lwK
public static LinkedList list=new LinkedList(); QQ^P IQj
/** Creates a new instance of CountCache */ ]Z%9l(
public CountCache() {} -:]_DbF
public static void add(CountBean cb){ ~LqjWU
if(cb!=null){ swEE >=
list.add(cb); BMMWP
} <Uf?7
} ^"N]i`dIF
} W=j
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CountControl.java C,$$bmS=
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/* Tov !X8p
* CountThread.java cC@B\Q
* V4kt&61
* Created on 2007年1月1日, 下午4:57 AdV&w: ^yf
* G*.}EoA
* To change this template, choose Tools | Options and locate the template under Kv3cKNvu~
* the Source Creation and Management node. Right-click the template and choose @*kQZRGK7
* Open. You can then make changes to the template in the Source Editor. M-Gl".*f
*/ KneCMFy
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package com.tot.count; 2)oT\m
import tot.db.DBUtils; Kppi
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import java.sql.*; eP6`"<UM
/** {x$WBy9
* 3gN#[P
* @author 1#BMc%
*/ >;I$&
public class CountControl{ zyb>PEd.
private static long lastExecuteTime=0;//上次更新时间 GSck^o2{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ^i>Tm9vM
/** Creates a new instance of CountThread */ Bg.~#H
public CountControl() {} &|cg`m
public synchronized void executeUpdate(){ Hg<d%7.
Connection conn=null; VnqgN
PreparedStatement ps=null; _Ec9g^I10
try{ Kxs_R#k
conn = DBUtils.getConnection(); >6xZF'4
conn.setAutoCommit(false); JRfG]u6GU
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); CHxu%-g
for(int i=0;i<CountCache.list.size();i++){ !
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CountBean cb=(CountBean)CountCache.list.getFirst(); 4H@:|
CountCache.list.removeFirst(); #w_cos[I
ps.setInt(1, cb.getCountId()); h$3o]~t
ps.executeUpdate();⑴ 1yHlBeEC
//ps.addBatch();⑵ K1i@.`na/$
} B.)!zv\{
//int [] counts = ps.executeBatch();⑶ 53>y<
conn.commit(); DL$O274uZ
}catch(Exception e){ RE~9L5i5
e.printStackTrace(); `<}Q4p
} finally{ dV_ClH &)
try{ ECq(i(
if(ps!=null) { /{h@A~<96
ps.clearParameters(); /1A3
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ps.close(); PtP{_9%Dz
ps=null; 2Fwp\I;
} =QG@{?JTl
}catch(SQLException e){} QnHb*4<
DBUtils.closeConnection(conn); 4KH8dau.fF
} .;),e#
} `xb\)
public long getLast(){ r57CyO
return lastExecuteTime; ,|:TML
} `v;9!ReZV
public void run(){ C%#%_
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long now = System.currentTimeMillis(); zvJQ@i"Z
if ((now - lastExecuteTime) > executeSep) { |%p;4b
//System.out.print("lastExecuteTime:"+lastExecuteTime); l;+nL[%`
//System.out.print(" now:"+now+"\n"); 9
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Q)`3&b
lastExecuteTime=now; QYl
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executeUpdate(); 2VB|a;Mo
} [diUO1p
else{ dY|~"6d)
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); _[J @w .l(
} 5W%^g_I
} e,*E`ol
} [WZGu6$SU
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 !'yCB9]O
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类写好了,下面是在JSP中如下调用。 OAlV7cfD
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<% g7Xjo )
CountBean cb=new CountBean(); DcjF$E
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |AgdD
CountCache.add(cb); j%_{tB
out.print(CountCache.list.size()+"<br>"); ?%)G%2
CountControl c=new CountControl(); ;^fGQ]`4
c.run(); j.}@ 9
out.print(CountCache.list.size()+"<br>"); _SVIY@K|/
%>