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: yd>kJk^~/
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CountBean.java : PQA9U|
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/* 'OF)`5sj
* CountData.java I<[(hPQUf
* qn4Dm ^
* Created on 2007年1月1日, 下午4:44 \a|gzC1G
* 2.; OHQTE
* To change this template, choose Tools | Options and locate the template under ZO0_:T#Z
* the Source Creation and Management node. Right-click the template and choose _KD(V2W
* Open. You can then make changes to the template in the Source Editor. s'LG3YV-<
*/ R`s /^0
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package com.tot.count; lG jdDqi
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/** oZOFZ-<
* s'/.eaV_
* @author ym ,S/Uz
*/ ]YOQIzkL4}
public class CountBean { :%!SzI?
private String countType; ,[cWG)-
int countId; gB
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/** Creates a new instance of CountData */ %M'"%Yn@(y
public CountBean() {} hi.{
public void setCountType(String countTypes){ ;B1}so1]
this.countType=countTypes; C ,fIwqOr3
} 'n>|jw)
public void setCountId(int countIds){ %f:'A%'Qb
this.countId=countIds; JTz1M~
} @&h<jM{D
public String getCountType(){ BDB-OJ
return countType; ;39{iU.m
} h ]MSjC.X
public int getCountId(){ UbMcXH8=F
return countId; xFyMg&
} ^z)lEO
} ]~a!O
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CountCache.java 1f}S:Z
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/* SkPv.H0Id
* CountCache.java ODEy2).
* [ >vS+G
* Created on 2007年1月1日, 下午5:01 ;gW~+hW ^
* {P = {)
* To change this template, choose Tools | Options and locate the template under dB_\,%vAd
* the Source Creation and Management node. Right-click the template and choose b_wb!_
* Open. You can then make changes to the template in the Source Editor. %lV>Nc|iz=
*/ w)!(@}vd
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package com.tot.count; HkrNh>^=
import java.util.*; M{nz~W80
/** Ulktd^A\
* 75^-93
* @author jhg!K.A
*/ mZq*o<kTA
public class CountCache { =8tduB
public static LinkedList list=new LinkedList(); !gT6So
/** Creates a new instance of CountCache */ -u8@ .
public CountCache() {} ?Bh}
public static void add(CountBean cb){
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if(cb!=null){ w#JF7;
list.add(cb); RNi&OG(
} Oe;9[=L[
} 2etlR
} T /]ayc:
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CountControl.java 5dL-v&W
% yJs"%
/* "BzRLg!J
* CountThread.java Zr$PSp}
* VQ}=7oe%q
* Created on 2007年1月1日, 下午4:57 XeZv%` ?
* ?G8 D6
* To change this template, choose Tools | Options and locate the template under [{Y$]3?}
* the Source Creation and Management node. Right-click the template and choose KNK0w 5
* Open. You can then make changes to the template in the Source Editor. @j^qT-0M
*/ 1TbKnmTx
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package com.tot.count; 'z!I#Y!Y
import tot.db.DBUtils; BJ&>'rc
import java.sql.*; x"N,oDs
/** wI`uAZ="
* 4vy!'r@
* @author |d,1mmv@K
*/ g[eI-J+F
public class CountControl{ S++}kR);
private static long lastExecuteTime=0;//上次更新时间 ZZeqOu7^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g5Hs= c5=\
/** Creates a new instance of CountThread */ b LxV
public CountControl() {} 9Y/c<gbY
public synchronized void executeUpdate(){ HVk3F|]V
Connection conn=null; :b.#h7Qt<
PreparedStatement ps=null; <p<gx*%
try{ SS H/q/
conn = DBUtils.getConnection(); 8:0l5cZE
conn.setAutoCommit(false); }>h?W1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >i=O =w
for(int i=0;i<CountCache.list.size();i++){ %K%8
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CountBean cb=(CountBean)CountCache.list.getFirst(); [[bMYD1eO
CountCache.list.removeFirst();
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ps.setInt(1, cb.getCountId()); @AyC0}
ps.executeUpdate();⑴ 1"!<e$&$X
//ps.addBatch();⑵ F<^,j7@
} ^Yn6kF
//int [] counts = ps.executeBatch();⑶ 5E.cJ{
conn.commit(); ^ qE4:|e
}catch(Exception e){ )@Bt[mfrVD
e.printStackTrace(); "@Te!.~A.
} finally{ k_y@vW3
try{ #G]s.by('
if(ps!=null) { ^K;,,s;0
ps.clearParameters(); 9MGA#a
ps.close(); :jUd?(
ps=null; %n-LDn
} yyiZV\ /
}catch(SQLException e){} [F6=JZ
DBUtils.closeConnection(conn); 3z5,4ps
} t[^}/
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} X@\! \
public long getLast(){ YjsaTdZ!&
return lastExecuteTime; _@d.wfM
} v3hNvcMpf
public void run(){ *1>XlVx,
long now = System.currentTimeMillis(); @9QHv
if ((now - lastExecuteTime) > executeSep) { %r|fuwwJO
//System.out.print("lastExecuteTime:"+lastExecuteTime); 1`h`-dqr#
//System.out.print(" now:"+now+"\n"); OCRx|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); KK7Y"~ 9&-
lastExecuteTime=now; o+q5:vJt
executeUpdate(); <xc"y|7X
} qWP1i7]=/
else{ a_pkUOu6
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); s+0$_&xR
} 6}|/~n
} r3iNfY b
} Fl|u0SY
//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 ?EYF61?
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类写好了,下面是在JSP中如下调用。 d B?I(
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U8}sp
<% z3a
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CountBean cb=new CountBean(); l
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); @gTpiV2
CountCache.add(cb); 5V%K'a(
out.print(CountCache.list.size()+"<br>"); 7OW;omT`
CountControl c=new CountControl(); N;ssO,
c.run(); wRLkO/Fw
out.print(CountCache.list.size()+"<br>"); Kj'm<]u
%>