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: a
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CountBean.java \x$`/
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/* 9Znc|<
* CountData.java d. d J^M
* vy2<'V*y}
* Created on 2007年1月1日, 下午4:44 R-$w*=Y
* ]UIN4E
* To change this template, choose Tools | Options and locate the template under 'O 7:=l
* the Source Creation and Management node. Right-click the template and choose v2rzHzFU
* Open. You can then make changes to the template in the Source Editor. (soTkH:#
*/ |{|B70v3Co
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package com.tot.count; =M:Po0?0E
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/** a(IE8:yU`
* DMA7eZf'Hv
* @author %npLgCF
*/ P;(@"gD8z5
public class CountBean { O_s/BoB@
private String countType; f.` 8vaV
int countId; q9x@Pc29d
/** Creates a new instance of CountData */ yU(}1ZID
public CountBean() {} N
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public void setCountType(String countTypes){ xxzUey
this.countType=countTypes; f
} r
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} CUdpT$ $x3
public void setCountId(int countIds){ .>,Y
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this.countId=countIds; _3u3b/%J?
} D;2V|CkU
public String getCountType(){ GYy8kp84
return countType; 3,Z;J5VL4!
} ,c&t#mu*0
public int getCountId(){ @lM-+q(tl
return countId; vS ( Y_6
} ,;YNI
} V4u4{wU]
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CountCache.java 2OI 0B\
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/* Uun0FCA>
* CountCache.java )6"p@1\u
* hG`@#9|f
* Created on 2007年1月1日, 下午5:01 _&G_SNa
* 0zr%8Q(Q
* To change this template, choose Tools | Options and locate the template under N:'GNMu
* the Source Creation and Management node. Right-click the template and choose &B:L9^
* Open. You can then make changes to the template in the Source Editor. [+5g 9tBJ
*/ 2T%sHp~qt
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package com.tot.count; 3bd`q
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import java.util.*; w&}<b%l
/** b&,ZmDJh
* g~|vmVBua
* @author 5m@'( ]j
*/ ?~sNu k
public class CountCache { hX,RuI
public static LinkedList list=new LinkedList(); 3y$6}Kp4?
/** Creates a new instance of CountCache */ ]n@T5*=
public CountCache() {} EBWM8~Nm#
public static void add(CountBean cb){ _8SB+s*
if(cb!=null){ ])v61B
list.add(cb); IrRe6nf@K
} =>o !
} |gk4X%o6
} a`9pHH:7Q
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CountControl.java %c$|.TkX
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/* }/tf^@
* CountThread.java 2>.b~q@
* $M,Q"QL
* Created on 2007年1月1日, 下午4:57 IEM{?
* pi70^`@ 'B
* To change this template, choose Tools | Options and locate the template under [Djx@x
* the Source Creation and Management node. Right-click the template and choose | Wj=%Ol%o
* Open. You can then make changes to the template in the Source Editor. npytb*[|c
*/ zSMM?g^T
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package com.tot.count; 39[ylR|\
import tot.db.DBUtils; 2ER_?y
import java.sql.*; nT~XctwF
/** 5D-as9k*
* eMEKR5*-O
* @author 1f"}]MbLR
*/ [".94(qs
public class CountControl{
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private static long lastExecuteTime=0;//上次更新时间 8.%wnH
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 VqD_FS;E
/** Creates a new instance of CountThread */ f]sR4mhO
public CountControl() {} iz [IK%K
public synchronized void executeUpdate(){ U![$7k>,pr
Connection conn=null; Dbx zqd
PreparedStatement ps=null; h1B_*L
try{ xe.f]a
conn = DBUtils.getConnection(); xHx_!
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conn.setAutoCommit(false); [(3 %$?[
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 03 iy[~Y2
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); ~ e<,GUx(]
CountCache.list.removeFirst(); V3|"
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ps.setInt(1, cb.getCountId()); Zy)iNNtn
ps.executeUpdate();⑴ T1?9E{bC8A
//ps.addBatch();⑵ Cnc=GTRi
} G^;]]Ji"
//int [] counts = ps.executeBatch();⑶ [P6A$HC<
conn.commit(); BTOl`U
}catch(Exception e){ >pol'=
e.printStackTrace(); cN2Pl%7
} finally{ n Jz* }=
try{ uHZjpMoM
if(ps!=null) { xrlyph5mE
ps.clearParameters(); (Xzq(QV
ps.close(); z#n+iC$9
ps=null; -J'ked
} pp#!sRUKPV
}catch(SQLException e){} %k"hzjXAw
DBUtils.closeConnection(conn); &liFUP?
} 1Qjc*+JzO.
} vUL@i'0&o
public long getLast(){ S@
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return lastExecuteTime; )Fqtb;W=
} x a\~(B.
public void run(){ F7=\*U
long now = System.currentTimeMillis(); "*c&[ALw
if ((now - lastExecuteTime) > executeSep) { t82*rCIB{
//System.out.print("lastExecuteTime:"+lastExecuteTime); z0Y L,
//System.out.print(" now:"+now+"\n"); 9Ns%<FRO@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ;_ 1Rk&o!
lastExecuteTime=now; R+U*]5~R
executeUpdate(); U(~Nmo'
} *y+K{ fM1
else{ /L]@k`.q@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .345%j
} KAT"!b
} =:TQ_>$Nc2
} KZ=5"a
//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 V.+a}J=Cw
W=#jtU`:5
类写好了,下面是在JSP中如下调用。 gId
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<% nkN2Bqt$
CountBean cb=new CountBean(); C(KV5c
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); wk=s3^
CountCache.add(cb); x6\^dVR}
out.print(CountCache.list.size()+"<br>"); }\A0g}
CountControl c=new CountControl(); uc=u4@.>
c.run(); pJo4&Ff
out.print(CountCache.list.size()+"<br>"); Hg\H>Z
%>