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: r_T)|||v
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CountBean.java b#VtPn]
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/*
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* CountData.java GcBqe=/B!
* Yuvi{ 0
* Created on 2007年1月1日, 下午4:44 ]5ZXgz
* ,d#*i
* To change this template, choose Tools | Options and locate the template under 8u[_t.y4m
* the Source Creation and Management node. Right-click the template and choose WK{`_c
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* Open. You can then make changes to the template in the Source Editor. 51|ky-
*/
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package com.tot.count; s3>a
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/** 6nx\|F
* zHJCXTM
* @author s)^/3a
*/ ={BD*=i
public class CountBean { j q+(2
private String countType; #HUn~r
int countId; yXJhOCa
/** Creates a new instance of CountData */ x?h/e;
public CountBean() {} 9K+>;`
public void setCountType(String countTypes){ 2\xw2VQ@P
this.countType=countTypes; zx.qN
} 1h,iWHC
public void setCountId(int countIds){ /5@YZ?|#2
this.countId=countIds; &.)=>2
} |2(q9j
public String getCountType(){ ;ArwEzo(
return countType; CFtQPTw
} }%wd1`l7
public int getCountId(){ 3lP;=*m.
return countId; 'a~@q~!
} ~ ld.I4
} t>j_C{X1(
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CountCache.java <kn2
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/* `[/#,*\
* CountCache.java <L}@p8Lq
* ?
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* Created on 2007年1月1日, 下午5:01 :j\7</uu
* &jqaW2
* To change this template, choose Tools | Options and locate the template under )x.%PUA
* the Source Creation and Management node. Right-click the template and choose iU)I"#\l'k
* Open. You can then make changes to the template in the Source Editor. T ,lM(2S[
*/ }3Es&p$9
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package com.tot.count; D!j/a!MaKk
import java.util.*; xGd60"w2
/** RT[p!xL
* cx\"r
* @author .;? Bni
*/ {U5sRM|I
public class CountCache { pBsb>wvej
public static LinkedList list=new LinkedList(); dY1t3@E
/** Creates a new instance of CountCache */ :qzg?\(
public CountCache() {} o E+'@
public static void add(CountBean cb){ q<YM,%mgj
if(cb!=null){ B%F]K<
list.add(cb); L}Z.FqJ
} *$Q>Om]
} iq&3S 0
} ipSMmpB
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CountControl.java Eb3 ZM#
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/* )%(ZFn}
* CountThread.java u6|C3,!z"
* oF%m
* Created on 2007年1月1日, 下午4:57 kg/ B<w'
* \/
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* To change this template, choose Tools | Options and locate the template under U8_{MY-9}
* the Source Creation and Management node. Right-click the template and choose hRkCB
* Open. You can then make changes to the template in the Source Editor. |$Yk)z3
*/ sI>w#1.m/&
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package com.tot.count; g6M>S1oOO
import tot.db.DBUtils; z/7q#~J,
import java.sql.*; E7uIur=g!
/** ]c(FgYc
* +R'8$
* @author PRhC1#
*/ aV;|2}q "
public class CountControl{ g )hEzL0k
private static long lastExecuteTime=0;//上次更新时间 !3b& S4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 66=[6U9 *
/** Creates a new instance of CountThread */ %4~"$kE
public CountControl() {} Jqoo&T")
public synchronized void executeUpdate(){ Yh<F-WOo2
Connection conn=null; 6 @f>
PreparedStatement ps=null; \u[x<-\/6
try{ &V38)83a
conn = DBUtils.getConnection(); H<Snp)
conn.setAutoCommit(false); SmXoNiM"y
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); F`D$bE;|
for(int i=0;i<CountCache.list.size();i++){ h:Pfiw]
CountBean cb=(CountBean)CountCache.list.getFirst(); N/a4Gl(
CountCache.list.removeFirst(); |Ajd$+3
ps.setInt(1, cb.getCountId()); J;4x$BI
ps.executeUpdate();⑴ 6-U_TV
//ps.addBatch();⑵ 9q;O`&
} !BQt+4G7
//int [] counts = ps.executeBatch();⑶ $QJ3~mG2
conn.commit(); *i"9D:
}catch(Exception e){ xm m,-u
e.printStackTrace(); o/AG9|()4
} finally{ ,np=m17
try{ 2Kxb(q"
if(ps!=null) { v93b8/1
ps.clearParameters(); {&1L &f<
ps.close(); cy%M$O|hX5
ps=null; _}[
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} "Q: Gd6?h;
}catch(SQLException e){} x^s,<G
DBUtils.closeConnection(conn); f;E#CjlTL
} +d,
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} ieyK$q
public long getLast(){ Ez1eGPVr
return lastExecuteTime; ?P9aXwc
} f)sy-o!
public void run(){ .; MS78BR
long now = System.currentTimeMillis(); 1RAkqw<E
if ((now - lastExecuteTime) > executeSep) { H/a gt
//System.out.print("lastExecuteTime:"+lastExecuteTime); eMGJx "a
//System.out.print(" now:"+now+"\n"); z}vT8qoX
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6wlLE5
lastExecuteTime=now; &h:4TaD
executeUpdate(); Bii'^^I;?
} !vz'zy)7
else{ hFV,FBsAO
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); r S@/@jKZE
} [6VB&
} Z`TfS+O6
} 1/$PxQ
//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 -2hirA<^
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类写好了,下面是在JSP中如下调用。 xe@e#9N$
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<% #:6-O
CountBean cb=new CountBean(); 7Ae`>5B#
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); X,Ql6uO
CountCache.add(cb); D||0c"E
out.print(CountCache.list.size()+"<br>"); LOU P
CountControl c=new CountControl(); BlJiHz!
c.run(); w:\} B'u
out.print(CountCache.list.size()+"<br>"); !5,C"r
%>