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: =j{tFxJ
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CountBean.java in5e *
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/* -Lq2K3JHyn
* CountData.java V1,/qd_
* g*(z.
* Created on 2007年1月1日, 下午4:44 GXIzAB(
* &2U%/JqY
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose a#{"3Z2|
* Open. You can then make changes to the template in the Source Editor. :b*7TJ\grN
*/ G"m?2$^-A
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package com.tot.count; {F2Rv
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/** f,F1k9-1!
* W/%hS)75
* @author '6})L
*/ 7{(UiQbf
public class CountBean { ] jY^*o[
private String countType; -8Hc M\b
int countId; 5eE\
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/** Creates a new instance of CountData */ o2=):2x
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public CountBean() {} 8sU5MQ5
public void setCountType(String countTypes){ 4'=Q:o*w`
this.countType=countTypes; 8zpzVizDG
} "\O7_od-
public void setCountId(int countIds){ Yku6\/^
this.countId=countIds; 6PYm?i=p?
} -KV,l
public String getCountType(){ @0s'
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return countType; w/O'&],x
} 6T|Z4f|
public int getCountId(){ *oeXmY
return countId; .ARM~{q6)@
} 4# PxJG6m
} ;ne`ppz0
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CountCache.java .d}yQ#5z
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/* {lH'T1^m
* CountCache.java ?O+.
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* Created on 2007年1月1日, 下午5:01 V8):!
* 2J{vfF
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose (oR~%2K
* Open. You can then make changes to the template in the Source Editor. xZ)K#\
*/
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package com.tot.count; YPGzI]\
import java.util.*; dqJ 8lU?
/** fv#ov+B
* "acI:cl?,
* @author xGQP*nZ
*/ W4&8
public class CountCache { k}F7Jw#.
public static LinkedList list=new LinkedList(); Z{BK@Q4z
/** Creates a new instance of CountCache */ R.*;] R>M
public CountCache() {} <W!n lh
public static void add(CountBean cb){ 2I}+AW!!=
if(cb!=null){ =.;ib6M
list.add(cb); Za1mI^ L1
} xjiV9{w
} z/`+jIB
} .:f ao'
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CountControl.java K=HLMDs
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/* $x`HmL3Sb
* CountThread.java ZP!.C&O
* 3e;|KU
* Created on 2007年1月1日, 下午4:57 zl6]N3+4
*
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* To change this template, choose Tools | Options and locate the template under =WUL%MfW
* the Source Creation and Management node. Right-click the template and choose vR:#g;mnk
* Open. You can then make changes to the template in the Source Editor. D.:`]W|
*/ s|H7;.3gp
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package com.tot.count; TK18U*z7J
import tot.db.DBUtils; S+~;PmN9qL
import java.sql.*; x%r$/=
/** (kB
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* @author i_Q1\_m !
*/ Ycm .qud
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public class CountControl{ ~EY)c~H
private static long lastExecuteTime=0;//上次更新时间 "hI"4xSg
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 K"XwSZ/
/** Creates a new instance of CountThread */ T@.+bD
public CountControl() {} G gA:;f46
public synchronized void executeUpdate(){ X!LiekU!D
Connection conn=null; 9ybR+dGm+
PreparedStatement ps=null; Z(c
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try{ PdVx&BL*
conn = DBUtils.getConnection(); SQ> Yf\
conn.setAutoCommit(false); :t!J
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); PvV\b<Pe+
for(int i=0;i<CountCache.list.size();i++){ :*,!gf
CountBean cb=(CountBean)CountCache.list.getFirst(); ^|.T\
CountCache.list.removeFirst(); zO\_^A|8H
ps.setInt(1, cb.getCountId()); nVWU\$Ft
ps.executeUpdate();⑴ eA2*}"W
//ps.addBatch();⑵ &odQ&%X
} Zf}2c8Vc4
//int [] counts = ps.executeBatch();⑶ W|@SXO)DY
conn.commit(); {$[0YRNk
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}catch(Exception e){ .wd7^wI^S
e.printStackTrace(); %A~. NNbS
} finally{ 2= ;ZJ
try{ hfLe<,
if(ps!=null) { sj&(O@~R
ps.clearParameters(); lshSRir
ps.close(); ufR>*)_+
ps=null; ag:<%\2c
} u c!6?+0h
}catch(SQLException e){} ,B/TqPP
DBUtils.closeConnection(conn); ~h8k4eM
} ,Aq, f$5V
} i: UN
public long getLast(){ |>U<EtA"
return lastExecuteTime; 2 N &B
} }])j>E
public void run(){ [7`S`\_NK
long now = System.currentTimeMillis(); 8q9^
if ((now - lastExecuteTime) > executeSep) { l2Py2ZI-b
//System.out.print("lastExecuteTime:"+lastExecuteTime); b_{+O qI
//System.out.print(" now:"+now+"\n"); Th%w-19,8
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); lmoYQFkYP
lastExecuteTime=now; |AvsT{2
executeUpdate(); ~!TrC<ft
} ._x"b5C
else{ : ciwh
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -M]/Xv]
} !lEV^SQJs
} }.|a0N 5
} ZUB]qzmK
//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 ?UflK
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类写好了,下面是在JSP中如下调用。 w].DLoz
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CountBean cb=new CountBean(); NPBOG1q%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +gndW
CountCache.add(cb); C|FI4/-e
out.print(CountCache.list.size()+"<br>"); M-QQ
CountControl c=new CountControl(); b9.7j!W
c.run(); u8A,f}D 3
out.print(CountCache.list.size()+"<br>"); L~|_)4
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