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: e;rs!I!Yw
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CountBean.java )4GfT
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/* Ku,Efr
* CountData.java wZfR>|f
* &lI.N~Ao
* Created on 2007年1月1日, 下午4:44 n)`*{uv$
* {j:{wW.
* To change this template, choose Tools | Options and locate the template under Kn\Oj=4
* the Source Creation and Management node. Right-click the template and choose 8l!S<RA
* Open. You can then make changes to the template in the Source Editor. L>@0Nne7
*/ Fdc bmQ
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package com.tot.count; 6_zL#7E'
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/** A*\4C3a'%
* '^Sa|WXq
* @author oVC~RKA*
*/ b;soMilz
public class CountBean { ctt5t
private String countType; ;C{2*0"H|
int countId; u=rY
/** Creates a new instance of CountData */ S'E6#
public CountBean() {} 3kYUO-qw
public void setCountType(String countTypes){ hC6$>tl
this.countType=countTypes; )%,bog(x
} )%ja6Vg
public void setCountId(int countIds){ jgEiemh&
this.countId=countIds; [FyE{NfiJ%
} w`#lLl
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public String getCountType(){ m"U\;Mw?
return countType; S'3l<sY
} |:H[Y"$1;
public int getCountId(){ T w"^I*B
return countId; DeXnE$XH
} a |z{Bb
} $:
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CountCache.java .P ,\69g~A
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/* G VEjB;
* CountCache.java I[[rVts
* "me Jn/
* Created on 2007年1月1日, 下午5:01 ?]3`WJOj
* ,qvz:a
* To change this template, choose Tools | Options and locate the template under IK%j+UB
* the Source Creation and Management node. Right-click the template and choose H%faRUonz
* Open. You can then make changes to the template in the Source Editor. uv_*E`pN~
*/ ~=0zZTG
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package com.tot.count; /5yWvra
import java.util.*; N{Is2Ia
/** 5,?9#n\E,
* .4-;
* @author ;AG5WPI
*/ CH9#<?l
public class CountCache { 7qzI]
public static LinkedList list=new LinkedList(); [IV8
/** Creates a new instance of CountCache */ Ns1u0$fg
public CountCache() {} &NGlkn
public static void add(CountBean cb){ @.CPZT
if(cb!=null){ `86 9XE
list.add(cb); `?Y/:4
} Sl 6}5
} &+*jTE
} '>`bp25>
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CountControl.java y!aq}YS
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/* WfO6Fvx%
* CountThread.java t~@TUTbx
* `7N[rs9|S
* Created on 2007年1月1日, 下午4:57 1Z`<HW"
* ~Dkje
* To change this template, choose Tools | Options and locate the template under >Y{.)QS
* the Source Creation and Management node. Right-click the template and choose I S!B$
* Open. You can then make changes to the template in the Source Editor. *y N,e.t
*/ 7 v`Y*D
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package com.tot.count; ld2\/9+n
import tot.db.DBUtils; 2I>C A[qp
import java.sql.*; k#&y
/** >_&+gn${
* ,"}'NH@
* @author `^w5/v#
*/ NO9Jre
public class CountControl{ ;o8cfD .z
private static long lastExecuteTime=0;//上次更新时间 ]qv/+~Qs>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AK[9fxrE
/** Creates a new instance of CountThread */ {}lw%d?A
public CountControl() {} YTYYb#"Q
public synchronized void executeUpdate(){ 2@^8{
Connection conn=null; "$Rl9(}
PreparedStatement ps=null; lWOB!l
try{ M}@^8
conn = DBUtils.getConnection(); JBjz2$ZM
conn.setAutoCommit(false); L2K4nTA
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 0n3O;=[aV
for(int i=0;i<CountCache.list.size();i++){ b5H[~8mf
CountBean cb=(CountBean)CountCache.list.getFirst(); i>e7 5`9
CountCache.list.removeFirst(); |dXS+R1
ps.setInt(1, cb.getCountId()); .GS|H d
ps.executeUpdate();⑴ d~[>%&
//ps.addBatch();⑵ =ohdL_6
} 44_n5vp,T
//int [] counts = ps.executeBatch();⑶ M)3h 4yQ
conn.commit(); D;:lw]
}catch(Exception e){ 5(U.<
e.printStackTrace(); \6@}HFH
} finally{ <cWo]T`X!
try{ '5[L []A
if(ps!=null) { Gm.v-T$
ps.clearParameters(); l}<s~ip
ps.close(); 9prG@
ps=null; !5=3Y4bg1
} 7dU X(D,?
}catch(SQLException e){} B`KpaE]
DBUtils.closeConnection(conn); 8qBw;A)
} _;0:wXib=
} rtUdL,Hx
public long getLast(){ G-}
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return lastExecuteTime; !)&-\!M>
} 6NZf!7,B
public void run(){ &G'R{s&"
long now = System.currentTimeMillis(); =@ON>SmPs
if ((now - lastExecuteTime) > executeSep) { *4.f*3*
//System.out.print("lastExecuteTime:"+lastExecuteTime); TYLf..i<
//System.out.print(" now:"+now+"\n"); orL7y&w(v:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); wBmbn=>#S
lastExecuteTime=now; ExnszFX*
executeUpdate(); 1lx\Pz@ol
} _
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else{ /?by4v73P
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1 bv L
} 9`vse>,-hg
} 2@A7i<p
} ;N4mR6
//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 wV(_=LF
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类写好了,下面是在JSP中如下调用。 (r7~ccy4
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<% $x`U)pv
CountBean cb=new CountBean(); 9K%E+_7b
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ]n!pn#Q
CountCache.add(cb); n){\KIU/O
out.print(CountCache.list.size()+"<br>"); &,K;F'
CountControl c=new CountControl(); ]Q)TqwYF
c.run(); 3EzI~Zsx
out.print(CountCache.list.size()+"<br>");
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