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: :nA.j"@
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CountBean.java #wY0D_3@1
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/* ICC%,$C~l
* CountData.java :o46rBs
* Qm4o7x{q
* Created on 2007年1月1日, 下午4:44 G2Vv i[c
* `=UWqb(K_
* To change this template, choose Tools | Options and locate the template under k(t}^50^j
* the Source Creation and Management node. Right-click the template and choose *.#oxcll
* Open. You can then make changes to the template in the Source Editor. W,XTF
*/ oGa^/:6L
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package com.tot.count; 99xEm
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/** y5r4+2B
* |`TgX@,#9
* @author >J9oH=S6
*/ ]\ !5}L
public class CountBean { F$BbYf2i
private String countType; Dre2J<QL
int countId; ",6M)3{|c
/** Creates a new instance of CountData */ +M'
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public CountBean() {} a.N{-2ptH
public void setCountType(String countTypes){ Rk!X]-`=
this.countType=countTypes; yAL[[
} eET&pP3Rp
public void setCountId(int countIds){ [S5\#=_4S
this.countId=countIds; H0m|1
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} mKrh[nA
public String getCountType(){ 1 zw*/dp
return countType; 0}!\$"|D
} '3zc|eJt&
public int getCountId(){ A,sr[Pa@
return countId; Mmpfto%i
} `]Q:-h
} WSuww
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CountCache.java DL$@?.?I
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/* ,eTU/Q>{,&
* CountCache.java ;>n,:355L
* (=7Cs
* Created on 2007年1月1日, 下午5:01 hzk cP
* SkmT`*v@
* To change this template, choose Tools | Options and locate the template under :Nofp&
* the Source Creation and Management node. Right-click the template and choose ``wSc0\
* Open. You can then make changes to the template in the Source Editor. BNL;Biyt7
*/ +v=C@2T
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package com.tot.count; xlQBe-Wg
import java.util.*; ~ 4kc/a
/** @Y1s$,=xB
* @`gk|W3
* @author 8ji_#og
*/ AvfNwE
public class CountCache { @3zg=?3
public static LinkedList list=new LinkedList(); Z<vKQ4G
/** Creates a new instance of CountCache */ 3\XU_Xs(]
public CountCache() {} ,^C--tgZJg
public static void add(CountBean cb){ ZzSz%z_sE
if(cb!=null){ $m/)FnU/
list.add(cb); lhqg$lb
} dw*_(ys
} b:TLV`>/&
} x^y'P<ypw
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CountControl.java d8c=L8~jt
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/* ^zQ/mo,Z
* CountThread.java ;IZwTXu !S
* K1M%!JKh)x
* Created on 2007年1月1日, 下午4:57 #T'{ n1AI
* e]zBf;9J
* To change this template, choose Tools | Options and locate the template under ppVHLrUh
* the Source Creation and Management node. Right-click the template and choose QC}CRkp
* Open. You can then make changes to the template in the Source Editor. }khV'6"'|
*/ !WQ-=0cm
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package com.tot.count; Na]:_K5Dp
import tot.db.DBUtils; -C(crn
import java.sql.*; "W955?4m
/** J;8IY=
* P*3BB>FO
* @author 7%x[q}
*/ T?ZRiR)@
public class CountControl{ sN9&,&W1
private static long lastExecuteTime=0;//上次更新时间 c7x~{V8
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 PgF*
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/** Creates a new instance of CountThread */ N_W}*2(
public CountControl() {} s@K4u^$A
public synchronized void executeUpdate(){ H4&lb}
Connection conn=null; I
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PreparedStatement ps=null; #P0&ewy
try{ P-y jN
conn = DBUtils.getConnection(); dMv=gdY
conn.setAutoCommit(false); [+n*~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); P3+5?.p.
for(int i=0;i<CountCache.list.size();i++){ @tNz Q8
CountBean cb=(CountBean)CountCache.list.getFirst(); oAODp!_c
CountCache.list.removeFirst(); ^
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ps.setInt(1, cb.getCountId()); f!Y?S
ps.executeUpdate();⑴ ib#KpEk
//ps.addBatch();⑵ v&DI`xn~
} Vc&!OE
//int [] counts = ps.executeBatch();⑶ 5q3JI
conn.commit(); vWzm@
}catch(Exception e){ 4i)1'{e
e.printStackTrace(); Yvw(tj5_5
} finally{ c|e~BQdRw
try{ riY~%9iV'
if(ps!=null) { `u3EU*~W
ps.clearParameters(); pjKWtY@=X
ps.close(); U)fc*s
ps=null; !/'t5~x[
}
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}catch(SQLException e){} @ym v< Mo
DBUtils.closeConnection(conn); sJL&:!}V>
} nLbFg0?+t
} q9KHmhUD
public long getLast(){ ?~BC#B\>o
return lastExecuteTime; Elcj tYu4
} _hAcJ{Y
public void run(){ lA|
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long now = System.currentTimeMillis(); :%tU'w
if ((now - lastExecuteTime) > executeSep) { e2 4WW^S
//System.out.print("lastExecuteTime:"+lastExecuteTime); {Z(h.de
//System.out.print(" now:"+now+"\n"); =upeRY@u5
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); SA&Rep^
lastExecuteTime=now; ;w{tv($$
executeUpdate(); >*~L28Fyn
} `uv2H$
else{ U6glp@s
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); jl4rbzse
} ZQ4p(6a
} !`Fxa4i>
} [%"|G9
//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 CM/H9Kz.
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类写好了,下面是在JSP中如下调用。 sXLq*b?
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<% d~9A+m3b_
CountBean cb=new CountBean(); ^n*)7K[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); RuLi,'u
CountCache.add(cb); $t$ShT)
out.print(CountCache.list.size()+"<br>"); @E&J_un
CountControl c=new CountControl(); l5S aT,%
c.run(); ;v}GJ<3
out.print(CountCache.list.size()+"<br>"); j8v8uZ;x
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