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: EBl? oN7E
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CountBean.java 7\xGMCctM
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/* LqA&@
* CountData.java \)'o{l&
* +dgHl_,i
* Created on 2007年1月1日, 下午4:44 W-UMX',0zS
* 0/@ ^He8l
* To change this template, choose Tools | Options and locate the template under zXRq) ;s
* the Source Creation and Management node. Right-click the template and choose pi|P&?yw
* Open. You can then make changes to the template in the Source Editor. . \6q\7Ej
*/ 4`M7
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package com.tot.count; U:1cbD7|3
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/** +thkx$o
* $/p/9 -
* @author k~,({T<
*/ ! O~:
public class CountBean { 2/ES.>K!.
private String countType; <RaM@E
int countId; ZJ
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/** Creates a new instance of CountData */ ?n0Z4 8%
public CountBean() {} l1?$quM^V
public void setCountType(String countTypes){ `{GI^kgJ9
this.countType=countTypes; P56B~M_
} *@1(!A
public void setCountId(int countIds){ <QcQ.b
this.countId=countIds; .nG14i7C
} 6J""gyK.
public String getCountType(){ v%2 @M
return countType; + <4gJoI
} AIU=56+I\
public int getCountId(){ :kb2v1{\
return countId; 4[VW~x07
} Pn| ;VCh
} :{Mr~Co*
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CountCache.java )A1u uW (
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/* ](2\w9i%
* CountCache.java L)qDtXd4
* Nm.G,6<J
* Created on 2007年1月1日, 下午5:01 yPXa
* K}j["p<!
* To change this template, choose Tools | Options and locate the template under aB*'DDlx"r
* the Source Creation and Management node. Right-click the template and choose %p t^?
* Open. You can then make changes to the template in the Source Editor. w28&qNha
*/ mY1Gm|
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package com.tot.count; `:>N.9'o
import java.util.*; yRyUOTK
/** S8Ec.]T
* 9(AY7]6
* @author e\7AtlW"
*/ GVK c4HGt
public class CountCache { 1&.q#,EMn(
public static LinkedList list=new LinkedList(); $c0<I59&|
/** Creates a new instance of CountCache */ N7 ox#=g
public CountCache() {} hC
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public static void add(CountBean cb){ ,%X"Caz
if(cb!=null){ LuE0Hb"S8
list.add(cb); 9
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} #M5pQ&yZy
} ?;xL]~Q~1
} %5yP^BL0
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CountControl.java fG_<HJS(~
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/* D_)N!,i
* CountThread.java !(8)'<t9
* lK%)a +2
* Created on 2007年1月1日, 下午4:57 %F2T`?t:
* 57jDsQAj
* To change this template, choose Tools | Options and locate the template under =_=0l+\}
* the Source Creation and Management node. Right-click the template and choose {\u6Cj x
* Open. You can then make changes to the template in the Source Editor. X@pcL{T!
*/ Qu_=K_W
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package com.tot.count; Y~Z&h?H'}
import tot.db.DBUtils; qF3s&WI
import java.sql.*; K0'= O
/** TR&7AiqB
* 'TO/i:{\
* @author nJ2910"<
*/ cES8%UC^i
public class CountControl{ EL^j}P
private static long lastExecuteTime=0;//上次更新时间
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 9
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/** Creates a new instance of CountThread */ &ev#C%Nu
public CountControl() {} CsX@u#
public synchronized void executeUpdate(){ @QfbIP9
Connection conn=null; #9rCF 3P
PreparedStatement ps=null; #B6$r/%
try{ +#Ga}eCM
conn = DBUtils.getConnection(); KSve_CBOh
conn.setAutoCommit(false); 6ee1^>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); rKkFflOVO
for(int i=0;i<CountCache.list.size();i++){ Xk?Y
CountBean cb=(CountBean)CountCache.list.getFirst(); XYze*8xUb
CountCache.list.removeFirst(); j*_>/gi
ps.setInt(1, cb.getCountId()); q"-+`;^7(-
ps.executeUpdate();⑴ '>:%n
//ps.addBatch();⑵ k[a5D/b
} sp7#e%R\
//int [] counts = ps.executeBatch();⑶ -#`tS
conn.commit(); ZfU &X{
}catch(Exception e){ _Rk>yJD7s
e.printStackTrace(); 0
} |21YED
} finally{ ,?c=v`e
try{ Z jn![
if(ps!=null) { (vPE?^}b
ps.clearParameters(); '-V[tyE
ps.close(); l9+)h}
ps=null; P/[}$(&:
} tpQ8
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}catch(SQLException e){} |[iEi
DBUtils.closeConnection(conn); *t bgIW+h
} 7b*9
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} L.x`Jpq(3
public long getLast(){ +%H2;8{F
return lastExecuteTime; :v%iF!+.P
} Q94p*]W"
public void run(){ ow7*HN*
long now = System.currentTimeMillis(); |]'gd)%S\
if ((now - lastExecuteTime) > executeSep) { H><!
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//System.out.print("lastExecuteTime:"+lastExecuteTime); 6Tg'9|g
//System.out.print(" now:"+now+"\n"); 5 J
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); BYZllwxwTE
lastExecuteTime=now; @N6KZn|R
executeUpdate(); nnuJY$O;M
} |k<5yj4?
else{ (AT)w/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); kPYQcOK8
} RY9Ur
} X<uH [
} @#::C@V]
//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 @5\/L6SRfL
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类写好了,下面是在JSP中如下调用。 rW[7
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<% {W%/?d9m
CountBean cb=new CountBean(); BFPy~5W
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Wl{wY,u
CountCache.add(cb); D'
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out.print(CountCache.list.size()+"<br>"); DIWcX<s
CountControl c=new CountControl(); kYu"`_n}
c.run(); mU;\,96#
out.print(CountCache.list.size()+"<br>"); V/t-
%>