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: ;"M6}5dQ4
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CountBean.java d*8*9CpO:
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/* k]p|kutQCy
* CountData.java jSjC43lh
* {0,b[
* Created on 2007年1月1日, 下午4:44 t?"(Zb
* J%?5d:iN+
* To change this template, choose Tools | Options and locate the template under SJ]6_4=y*
* the Source Creation and Management node. Right-click the template and choose P!79{ 8
* Open. You can then make changes to the template in the Source Editor. (_ G>dP_
*/ |OeWM
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package com.tot.count; v>keZZOs
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/** NgTB4I8P
* +,,(8=5g
* @author -Cyo2wk
*/ {py%-W
public class CountBean { xX-r<:'tmi
private String countType; _eGYwBm
int countId; C:Jfrg`
/** Creates a new instance of CountData */ LDQ,SS,
public CountBean() {} V/#Ra
public void setCountType(String countTypes){ '8]p]#l
this.countType=countTypes;
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} 0`"oR3JY
public void setCountId(int countIds){ ;t0q
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this.countId=countIds; t`B@01;8A
} T +vo)9w
public String getCountType(){ 0si1:+t-[+
return countType; w=#'8ZuU
} sJZ2e6?n
public int getCountId(){ [W3X$r~-
return countId; wQG?)aaM
} ,ayEZ#4.m
} !=eNr<:V.
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CountCache.java iyn9[>je
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/* fG1iq<~
* CountCache.java Z3&}C h
* wp@_4Iq1$
* Created on 2007年1月1日, 下午5:01 (iq>]-=<
* +ydd"`
* To change this template, choose Tools | Options and locate the template under Xqw}O2QQ1
* the Source Creation and Management node. Right-click the template and choose ?9t4>xKn
* Open. You can then make changes to the template in the Source Editor. ~B|m"qY{i
*/ 1_t+lJI9j
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package com.tot.count; t+a.,$U
import java.util.*; ^i|R6oO_5
/** MsXw
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* nYSe0w
* @author [2-n*a(q
*/ *k7BE_&*0Z
public class CountCache { P<IDb%W
public static LinkedList list=new LinkedList(); Bf*>q*%B{
/** Creates a new instance of CountCache */ l WYp
public CountCache() {} :^ywc O
public static void add(CountBean cb){ o MJ`_
if(cb!=null){ K T0t4XPM
list.add(cb); Go{,<
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} "AUSgVE+h
} u9~5U9]O%6
} S L
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CountControl.java R ` ViRJh
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/* R ABw(b
* CountThread.java Tc(=J7*r&
* Wh i#Ii~
* Created on 2007年1月1日, 下午4:57 ]mMJ6n
* 42]7N3:'
* To change this template, choose Tools | Options and locate the template under Aax;0qGbH
* the Source Creation and Management node. Right-click the template and choose l~"T>=jq3
* Open. You can then make changes to the template in the Source Editor. KAnV%j
*/ jh/,G5RM9
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package com.tot.count; YH\9Je%jx
import tot.db.DBUtils; ~yJ 2@2I
import java.sql.*; |OJWQU![by
/** t~(jA9n
* &B&8$X
* @author !hq2AY&H)
*/ J'Pyn
public class CountControl{ vS\ 2zwb}
private static long lastExecuteTime=0;//上次更新时间 *,JE[M
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 o#p%IGG`
/** Creates a new instance of CountThread */ k4iiL<|
public CountControl() {} yU!1q}L!
public synchronized void executeUpdate(){ G$f%]A1
Connection conn=null; ^:-GPr
PreparedStatement ps=null; 6C&&="uww
try{ <kFLwF?PM'
conn = DBUtils.getConnection(); 7}VqXUwabx
conn.setAutoCommit(false); :m<&Ff}
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); rhc+tR
for(int i=0;i<CountCache.list.size();i++){ srf}+>u&
CountBean cb=(CountBean)CountCache.list.getFirst(); u0L-xC$L
CountCache.list.removeFirst(); YTa
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ps.setInt(1, cb.getCountId()); Wa|V~PL+T
ps.executeUpdate();⑴ d9$RmCHe}
//ps.addBatch();⑵ J[<Zy^"Y;
} UiG/Rn
//int [] counts = ps.executeBatch();⑶ ZMQ=D!kT
conn.commit(); 5Rl\& G\
}catch(Exception e){ uj6'T Sl
e.printStackTrace(); gbuh04#~
} finally{ Jx5`0?
try{ ??"_o3
if(ps!=null) { YHEn{z7
ps.clearParameters(); Ef#LRcG-Z
ps.close(); d[_26.
ps=null; *U^Y@""a
} 1x|3|snz)
}catch(SQLException e){} ,*iA38d.!
DBUtils.closeConnection(conn); bqE'9GI
}
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} ]$ "eGHX
public long getLast(){ i"G'#n~e
return lastExecuteTime; ?z1v_Jh
} Oin9lg-jR
public void run(){ a6LL]_&g
long now = System.currentTimeMillis(); n- 2X?<_Z
if ((now - lastExecuteTime) > executeSep) { >IIq_6Z#
//System.out.print("lastExecuteTime:"+lastExecuteTime); To*+Z3Wd
//System.out.print(" now:"+now+"\n"); S[K5ofV
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); bKpy?5&>
lastExecuteTime=now; +b-ON@9]J`
executeUpdate(); cp@Fj"
} 1@v<
else{ <}J!_$A
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); a|FkU%sjzZ
} 5e+j51
} !ekByD
} 6axxyh%
//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/f
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类写好了,下面是在JSP中如下调用。 Ow4 _0l&
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<% 4<-Kd~uL
CountBean cb=new CountBean(); eS!]..%y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 6o^>q&e}%
CountCache.add(cb); 57q=
out.print(CountCache.list.size()+"<br>"); M )ET1ZM
CountControl c=new CountControl(); ,4H? + |!
c.run(); 8@rYT5e3c
out.print(CountCache.list.size()+"<br>"); ceG\Q2
%>